Patent Application
20230149674
The present application relates to expandable introducer sheaths for the delivery of prosthetic devices such as transcatheter heart valves, and methods of making the same.
Endovascular delivery catheter assemblies are used to deliver surgical devices and prosthetic implants, such as a prosthetic valve, at locations inside the body that are not readily accessible by surgery or where access without invasive surgery is desirable. For example, aortic, mitral, tricuspid, and/or pulmonary prosthetic valves can be delivered to a treatment site using minimally invasive surgical techniques.
An introducer sheath can be used to safely introduce a delivery apparatus into a patient's vasculature (e.g., the femoral artery). An introducer sheath generally has an elongated sleeve that is inserted into the vasculature along with an introducer, and a housing that contains one or more sealing valves that allow a delivery apparatus to be placed in fluid communication with the vasculature with minimal blood loss. Such introducer sheaths may be radially expandable. However, such sheaths tend to have complex mechanisms, such as ratcheting mechanisms that maintain the sheath in an expanded configuration once a device with a larger diameter than the sheath's original diameter is introduced. Moreover, these introducer sheaths often include a compressed distal tip that is relatively stiffer than the remainder of the sheath body. The narrow and stiff distal tip can be formed by compressing and heating bonding the material of the sheath tip. While the bond between the material layers and/or the folded/compressed material is configured to break during passage of a medical device, a high push force is required causing possible damage to the medical device and risking trauma to the patient. Additionally, in some procedures, retraction of the medical device for replacement/repositioning and/or removal of other equipment is too large to fit through the distal opening of the sheath. For example, in the case of pre-implantation balloon aortic valvuloplasty (pre-BAV), the device passing through the tip is provided with a smaller diameter than that of the tip opening. A balloon may be delivered through the introducer sheath in a deflated state, having a diameter smaller than that of the sheath's tip (e.g., 10 Fr) such that the tip does not dilate when the balloon is passed distally there-through. After the pre-BAV procedure is complete, the diameter of the (deflated) balloon may be larger than that of the compressed tip, such that retraction of the balloon may face difficulties. Accordingly, there remains a need in the art for an improved introducer sheath for endovascular systems used for implanting valves and other prosthetic devices.
The expandable introducer disclosed herein includes: an elongated body member; an inflatable balloon disposed between a proximal and distal end of the elongated body member, the balloon expandable from a deflated configuration to an inflated configuration; and an inflation lumen in fluid communication with the inflatable balloon, the inflation sized and configured for providing an inflation fluid to the balloon. In the deflated configuration, an outer diameter of the balloon corresponds to an outer diameter of the elongated body member, and in the inflated configuration, the outer dimeter of the balloon is greater than the outer diameter of the elongated body member, and at least a portion of the balloon is sized and configured to pass through a distal opening of an expandable introducer sheath when the balloon is in the deflated condition, the balloon sized and configured to expand at least a portion of a distal end of an introducer sheath as the balloon is inflated.
Another expandable introducer sheath system disclosed herein includes: an expandable introducer sheath for deploying a medical device; an introducer received within a central lumen of the introducer sheath and axially and rotatably movable therein, the introducer comprising: an elongated body member having a proximal end and a tapered distal end; an inflatable balloon disposed between the proximal end and the distal end of the elongated body member, the balloon expandable from a deflated configuration to an inflated configuration; and an inflation lumen in fluid communication with the inflatable balloon, the inflation sized and configured for providing an inflation fluid to the balloon. In the deflated configuration, an outer diameter of the balloon corresponds to an outer diameter of the elongated body member, and in the inflated configuration, the outer dimeter of the balloon is greater than the outer diameter of the elongated body member. At least a portion of the balloon is sized and configured to pass through a distal opening of the introducer sheath when the balloon is in the deflated condition, as the balloon is inflated at least a portion of the distal end of an introducer sheath expands, increasing a diameter of the distal opening.
Methods of pre-dilating an introducer sheath tip are also disclosed herein. One example of pre-dilating an introducer sheath tip includes: positioning an expandable introducer within a central lumen of an expandable sheath, the introducer including: an elongated body member; an inflatable balloon disposed between a proximal and distal end of the elongated body member, the balloon expandable from a deflated configuration to an inflated configuration, when in the deflated configuration an initial diameter of the balloon corresponds to an outer diameter of the elongated body member, when in the inflated configuration, the inflated dimeter of the balloon is greater than the outer diameter of the elongated body member; and an inflation lumen in fluid communication with the inflatable balloon, the inflation sized and configured for providing an inflation fluid to the balloon. The method further includes advancing the introducer axially within the central lumen of the sheath such that the inflatable balloon is axially aligned with a distal opening of the sheath; inflating the balloon to the inflated diameter, where the inflated diameter of the balloon is greater than an initial diameter of the distal opening and thereby expanding a diameter of the distal opening of the sheath; deflating the balloon; and withdrawing the introducer from the central lumen of the sheath.
Methods of delivering a medical device using an expandable introducer are also disclosed herein. One example includes, inserting an expandable sheath and an expandable introducer at least partially into the vasculature of the patient, the introducer received within a central lumen of the sheath; advancing the introducer axially within the central lumen of the sheath such that an inflatable balloon disposed on an elongated body member of the introducer is axially aligned with a distal opening of the sheath; inflating the balloon to a diameter greater than an initial diameter of the distal opening and thereby expanding a diameter of the distal opening of the sheath; deflating the balloon; withdrawing the introducer from the central lumen of the sheath; advancing a medical device through the central lumen of the sheath; and delivering the medical device to the patient.
An expansion device that is configured to be received within an expandable sheath is also disclosed herein. The expansion device includes a body and a radially extending protrusion. The body includes an outer surface, a proximal end, and a tapered distal end opposite and spaced apart from the proximal end of the body. The radially extending protrusion is disposed along a portion of the body and includes an outer surface. The radially extending protrusion has a diameter greater than a diameter of the body. The device is sized and configured to be received within a central lumen of an expandable sheath such that the radially extending protrusion at least partially expands a portion of the expandable sheath.
Also disclosed herein is a sheath system. The sheath system includes an expandable sheath and an expansion device. The expandable sheath includes an inner layer defining a central lumen of the sheath and an outer layer extending at least partially around the inner layer. The inner layer and outer layer transition from a non-expanded and an expanded configuration. The expansion device is movable within the central lumen of the sheath. The expansion device includes a body and a radially extending protrusion. The body includes an outer surface, a proximal end and a tapered distal end opposite and spaced apart from the proximal end. The radially extending protrusion is disposed along a portion of the body and has an outer surface having a diameter greater than a diameter of the body. Receipt of the expansion device within the central lumen of the sheath causes the sheath to locally expand at least a portion of the sheath in response to the outwardly directed radial force provided by the radially extending protrusion.
A method of locally expanding an expandable sheath is also disclosed. The method includes introducing an expansion device within a central lumen of the expandable sheath; introducing the combined expandable sheath and expansion device into a patient's vascular; and advancing the expansion device distally within the central lumen of the expandable sheath to locally expand the lumen of the sheath at a local axial location corresponding to an axial location of a radially extending protrusion provided on the expansion device.
Another method of locally expanding an expandable sheath is also disclosed. The method includes introducing an expandable sheath into a patient's vascular, the expandable sheath having a central lumen; introducing the expansion device into the central lumen of the expandable sheath; and advancing the expansion device distally within the central lumen of the expandable sheath to locally expand the lumen of the sheath at a local axial location corresponding to an axial location of a radially extending protrusion provided on the expansion device.
Example features and implementations are disclosed in the accompanying drawings. However, the present disclosure is not limited to the precise arrangements shown, and the drawings are not necessarily drawn to scale.
Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures.
The expandable introducer sheaths described herein can be used to deliver a prosthetic device through a patient's vasculature to a procedure site within the body. The sheath can be constructed to be highly expandable and collapsible in the radial direction while limiting axial elongation of the sheath and, thereby, undesirable narrowing of the lumen. In one example, the expandable sheath includes a braided layer, one or more relatively thin, non-elastic polymeric layers, and an elastic layer. The sheath can resiliently expand from its natural diameter to an expanded diameter as a prosthetic device is advanced through the sheath, and can return to its natural diameter upon passage of the prosthetic device under the influence of the elastic layer. In certain examples, the one or more polymeric layers can engage the braided layer, and can be configured to allow radial expansion of the braided layer while preventing axial elongation of the braided layer, which would otherwise result in elongation and narrowing of the sheath.
The prosthetic heart valve 12 can be delivered into a patient's body in a radially compressed configuration and radially expanded to a radially expanded configuration at the desired deployment site. In the illustrated example, the prosthetic heart valve 12 is a plastically expandable prosthetic valve that is delivered into the patient's body in a radially compressed configuration on a balloon of the balloon catheter 16 (as shown in
In alternative examples, the introducer device 90 need not include a housing 92. For example, the sheath 100 can be an integral part of a component of the delivery apparatus 10, such as the guide catheter. For example, the sheath can extend from the handle 18 of the guide catheter. Various example sheaths are described herein. Like reference numbers and designations in the various drawings indicate like elements. Additional examples of introducer devices and expandable sheaths can be found in U.S. patent application Ser. No. 16/378,417, and U.S. Provisional Patent Application No. 62/912,569, filed Oct. 8, 2019 (also filed under International Application No. PCT/US2020/054594), which are incorporated by reference in their entirety.
Referring to
In certain examples, the inner layer 102 and/or the outer layer 108 can comprise a relatively thin layer of polymeric material. For example, in some sheaths 100 the thickness of the inner layer 102 can be from 0.01 mm to 0.5 mm, 0.02 mm to 0.4 mm, or 0.03 mm to 0.25 mm. In certain examples, the thickness of the outer layer 108 can be from 0.01 mm to 0.5 mm, 0.02 mm to 0.4 mm, or 0.03 mm to 0.25 mm.
In certain examples, the inner layer 102 and/or the outer layer 108 can comprise a lubricious, low-friction, and/or relatively non-elastic material. In particular examples, the inner layer 102 and/or the outer layer 108 can comprise a polymeric material having a modulus of elasticity of 400 MPa or greater. Exemplary materials can include ultra-high-molecular-weight polyethylene (UHMWPE) (e.g., Dyneema®), high-molecular-weight polyethylene (HMWPE), or polyether ether ketone (PEEK). With regard to the inner layer 102 in particular, such low coefficient of friction materials can facilitate passage of the prosthetic device through the lumen 112. Other suitable materials for the inner and outer layers can include polytetrafluoroethylene (PTFE), expanded polytetrafluoroethylene (ePTFE), ethylene tetrafluoroethylene (ETFE), nylon, polyethylene, polyether block amide (e.g., Pebax), and/or combinations of any of the above. Some examples of a sheath 100 can include a lubricious liner on the inner surface of the inner layer 102. Examples of suitable lubricious liners include materials that can further reduce the coefficient of friction of the inner layer 102, such as PTFE, polyethylene, polyvinylidine fluoride, and combinations thereof. Suitable materials for a lubricious liner also include other materials desirably having a coefficient of friction of 0.1 or less.
Additionally, some examples of the sheath 100 can include an exterior hydrophilic coating on the outer surface of the outer layer 108. Such a hydrophilic coating can facilitate insertion of the sheath 100 into a patient's vessel, reducing potential damage. Examples of suitable hydrophilic coatings include the Harmony™ Advanced Lubricity Coatings and other Advanced Hydrophilic Coatings available from SurModics, Inc., Eden Prairie, Minn. DSM medical coatings (available from Koninklijke DSM N.V, Heerlen, the Netherlands), as well as other hydrophilic coatings (e.g., PTFE, polyethylene, polyvinylidine fluoride), are also suitable for use with the sheath 100. Such hydrophilic coatings may also be included on the inner surface of the inner layer 102 to reduce friction between the sheath and the delivery system, thereby facilitating use and improving safety. In some examples, a hydrophobic coating, such as Perylene, may be used on the outer surface of the outer layer 108 or the inner surface of the inner layer 102 in order to reduce friction.
In certain examples, the second layer 104 can be a braided layer.
The braided layer 104 can extend along substantially the entire length L of the sheath 100, or alternatively, can extend only along a portion of the length of the sheath. In particular examples, the filaments 110 can be wires made from metal (e.g., Nitinol, stainless steel, etc.), or any of various polymers or polymer composite materials, such as carbon fiber. In certain examples, the filaments 110 can be round, and can have a diameter of from 0.01 mm to 0.5 mm, 0.03 mm to 0.4 mm, or 0.05 mm to 0.25 mm. In other examples, the filaments 110 can have a flat cross-section with dimensions of 0.01 mm×0.01 mm to 0.5 mm×0.5 mm, or 0.05 mm×0.05 mm to 0.25 mm×0.25 mm. In one example, filaments 110 having a flat cross-section can have dimensions of 0.1 mm×0.2 mm. However, other geometries and sizes are also suitable for certain examples. If braided wire is used, the braid density can be varied. Some examples have a braid density of from ten picks per inch to eighty picks per inch, and can include eight wires, sixteen wires, or up to fifty-two wires in various braid patterns. In other examples, the second layer 104 can be laser cut from a tube, or laser-cut, stamped, punched, etc., from sheet stock and rolled into a tubular configuration. The layer 104 can also be woven or knitted, as desired.
The third layer 106 can be a resilient, elastic layer (also referred to as an elastic material layer). In certain examples, the elastic layer 106 can be configured to apply force to the underlying layers 102 and 104 in a radial direction (e.g., toward the central axis 114 of the sheath) when the sheath expands beyond its natural diameter by passage of the delivery apparatus through the sheath. Stated differently, the elastic layer 106 can be configured to apply encircling pressure to the layers of the sheath beneath the elastic layer 106 to counteract expansion of the sheath. The radially inwardly directed force is sufficient to cause the sheath to collapse radially back to its unexpanded state after the delivery apparatus is passed through the sheath.
In the illustrated examples, the elastic layer 106 can comprise one or more members configured as strands, ribbons, or bands 116 helically wrapped around the braided layer 104. For example, in the illustrated example the elastic layer 106 comprises two elastic bands 116A and 116B wrapped around the braided layer with opposite helicity, although the elastic layer may comprise any number of bands depending upon the desired characteristics. The elastic bands 116A and 116B can be made from, for example, any of a variety of natural or synthetic elastomers, including silicone rubber, natural rubber, any of various thermoplastic elastomers, polyurethanes such as polyurethane siloxane copolymers, urethane, plasticized polyvinyl chloride (PVC), styrenic block copolymers, polyolefin elastomers, etc. In some examples, the elastic layer can comprise an elastomeric material having a modulus of elasticity of 200 MPa or less. In some examples, the elastic layer 106 can comprise a material exhibiting an elongation to break of 200% or greater, or an elongation to break of 400% or greater. The elastic layer 106 can also take other forms, such as a tubular layer comprising an elastomeric material, a mesh, a shrinkable polymer layer such as a heat-shrink tubing layer, etc. In lieu of, or in addition to, the elastic layer 106, the sheath 100 may also include an elastomeric or heat-shrink tubing layer around the outer layer 108. Examples of such elastomeric layers are disclosed in U.S. Publication No. 2014/0379067, U.S. Publication No. 2016/0296730, and U.S. Publication No. 2018/0008407, which are incorporated herein by reference. In other examples, the elastic layer 106 can also be radially outward of the polymeric layer 108.
In certain examples, one or both of the inner layer 102 and/or the outer layer 108 can be configured to resist axial elongation of the sheath 100 when the sheath expands. More particularly, one or both of the inner layer 102 and/or the outer layer 108 can resist stretching against longitudinal forces caused by friction between a prosthetic device and the inner surface of the sheath such that the length L remains substantially constant as the sheath expands and contracts. As used herein with reference to the length L of the sheath, the term “substantially constant” means that the length L of the sheath increases by not more than 1%, by not more than 5%, by not more than 10%, by not more than 15%, or by not more than 20%. Meanwhile, with reference to
For example, in some sheaths 100 the inner layer 102 and the outer layer 108 can be heat-bonded during the manufacturing process such that the braided layer 104 and the elastic layer 106 are encapsulated between the layers 102 and 108. More specifically, in certain examples the inner layer 102 and the outer layer 108 can be adhered to each other through the spaces between the filaments 110 of the braided layer 104 and/or the spaces between the elastic bands 116. The layers 102 and 108 can also be bonded or adhered together at the proximal and/or distal ends of the sheath. In certain examples, the layers 102 and 108 are not adhered to the filaments 110. This can allow the filaments 110 to move angularly relative to each other, and relative to the layers 102 and 108, allowing the diameter of the braided layer 104, and thereby the diameter of the sheath, to increase or decrease. As the angle θ between the filaments 110A and 110B changes, the length of the braided layer 104 can also change. For example, as the angle θ increases, the braided layer 104 can foreshorten, and as the angle θ decreases, the braided layer 104 can lengthen to the extent permitted by the areas where the layers 102 and 108 are bonded. However, because the braided layer 104 is not adhered to the layers 102 and 108, the change in length of the braided layer that accompanies a change in the angle θ between the filaments 110A and 110B does not result in a significant change in the length L of the sheath.
Meanwhile, the angle θ between the filaments 110A and 110B can increase as the sheath expands to the second diameter D2 to accommodate the prosthetic valve. This can cause the braided layer 104 to foreshorten. However, because the filaments 110 are not engaged or adhered to the layers 102 or 108, the shortening of the braided layer 104 attendant to an increase in the angle θ does not affect the overall length L of the sheath. Moreover, because of the longitudinally-extending folds 126 formed in the layers 102 and 108, the layers 102 and 108 can expand to the second diameter D2 without rupturing, in spite of being relatively thin and relatively non-elastic. In this manner, the sheath 100 can resiliently expand from its natural diameter D1 to a second diameter D2 that is larger than the diameter D1 as a prosthetic device is advanced through the sheath, without lengthening, and without constricting. Thus, the force required to push the prosthetic implant through the sheath is significantly reduced.
Additionally, because of the radial force applied by the elastic layer 106, the radial expansion of the sheath 100 can be localized to the specific portion of the sheath occupied by the prosthetic device. For example, with reference to
In addition to the advantages above, the expandable sheath examples described herein can provide surprisingly superior performance relative to known introducer sheaths. For example, it is possible to use a sheath configured as described herein to deliver a prosthetic device having a diameter that is two times larger, 2.5 times larger, or even three times larger than the natural outer diameter of the sheath. For example, in one example a crimped prosthetic heart valve having a diameter of 7.2 mm was successfully advanced through a sheath configured as described above and having a natural outer diameter of 3.7 mm. As the prosthetic valve was advanced through the sheath, the outer diameter of the portion of the sheath occupied by the prosthetic valve increased to 8 mm. In other words, it was possible to advance a prosthetic device having a diameter more than two times the outer diameter of the sheath through the sheath, during which the outer diameter of the sheath resiliently increased by 216%. In another example, a sheath with an initial or natural outer diameter of 4.5 mm to 5 mm can be configured to expand to an outer diameter of 8 mm to 9 mm.
In alternative examples, the sheath 100 may optionally include the layer 102 without the layer 108, or the layer 108 without the layer 102, depending upon the particular characteristics desired.
In the illustrated examples, the braided layer 104 is disposed between the polymeric layers 102 and 108, as described above. For example, the polymeric layers 102 and 108 can be adhered or laminated to each other at the ends of the sheath 100 and/or between the filaments 110 in the open spaces 136 defined by the unit cells 134. Thus, with reference to
Turning now to methods of making expandable sheaths,
With reference to
In particular examples, the elastic bands 116 can be applied to the braided layer 104 in a stretched, taut, or extended condition. For example, in certain examples the bands 116 can be applied to the braided layer 104 stretched to a length that is twice their natural, relaxed length. This will cause the completed sheath to radially collapse under the influence of the elastic layer when removed from the mandrel, which can cause corresponding relaxation of the elastic layer, as described below. In other examples, the layer 102 and the braided layer 104 can be removed from the mandrel, the elastic layer 106 can be applied in a relaxed state or moderately stretched state, and then the assembly can be placed back on the mandrel such that the elastic layer is radially expanded and stretched to a taut condition prior to application of the outer layer 108.
The assembly can then be heated to a sufficiently high temperature that the heat-shrink layer 124 shrinks and compresses the layers 102-108 together. In certain examples, the assembly can be heated to a sufficiently high temperature such that the polymeric inner and outer layers 102 and 108 become soft and tacky, and bond to each other in the open spaces between the braided layer 104 and the elastic layer 106 and encapsulate the braided layer and the elastic layer. In other examples, the inner and outer layers 102, 108 can be reflowed or melted such that they flow around and through the braided layer 104 and the elastic layer 106. In one example, the assembly can be heated at 150° C. for 20-30 minutes.
After heating, the sheath 100 can be removed from the mandrel 118, and the heat-shrink tubing 124 and the ePTFE layers 120 and 122 can be removed. Upon being removed from the mandrel 118, the sheath 100 can at least partially radially collapse to the natural design diameter D1 under the influence of the elastic layer 106. In certain examples, the sheath can be radially collapsed to the design diameter with the optional aid of a crimping mechanism. The attendant reduction in circumference can buckle the filaments 110 as shown in
In certain examples, a layer of PTFE can be interposed between the ePTFE layer 120 and the inner layer 102, and/or between the outer layer 108 and the ePTFE layer 122, in order to facilitate separation of the inner and outer polymeric layers 102, 108 from the respective ePTFE layers 120 and 122. In further examples, one of the inner layer 102 or the outer layer 108 may be omitted, as described above.
The expandable sheath 100 can also be made in other ways. For example,
The containment vessel 202 can define an interior volume or chamber 204. In the illustrated examples, the vessel 202 can be a metal tube including a closed end 206 and an open end 208. The vessel 202 can be at least partially filled with a thermally-expandable material 210 having a relatively high coefficient of thermal expansion. In particular examples, the thermally-expandable material 210 may have a coefficient of thermal expansion of 2.4×10−4/° C. or greater. Exemplary thermally-expandable materials include elastomers such as silicones materials. Silicone materials can have a coefficient of thermal expansion of from 5.9×10−4/° C. to 7.9×10−4/° C.
A mandrel similar to the mandrel 118 of
The open end 208 of the vessel 202 can be closed with a cap 212. The vessel 202 can then be heated by the heating system 214. Heating by the heating system 214 can cause the material 210 to expand within the chamber 204 and apply radial pressure against the layers of material on the mandrel 118. The combination of the heat and pressure can cause the layers on the mandrel 118 to bond or adhere to each other to form a sheath. In certain examples, it is possible to apply radial pressure of 100 MPa or more to the mandrel 118 using the apparatus 200. The amount of radial force applied to the mandrel can be controlled by, for example, the type and quantity of the material 210 selected and its coefficient of thermal expansion, the thickness of the material 210 surrounding the mandrel 118, the temperature to which the material 210 is heated, etc.
In some examples, the heating system 214 can be an oven into which the vessel 202 is placed. In some examples, the heating system can include one or more heating elements positioned around the vessel 202. In some examples, the vessel 202 can be an electrical resistance heating element or an induction heating element controlled by the heating system 214. In some examples, heating elements can be embedded in the thermally-expandable material 210. In some examples, the material 210 can be configured as a heating element by, for example, adding electrically conductive filler materials, such as carbon fibers or metal particles.
The apparatus 200 can provide several advantages over known methods of sheath fabrication, including uniform, highly controllable application of radial force to the mandrel 118 along its length, and high repeatability. The apparatus 200 can also facilitate fast and accurate heating of the thermally-expandable material 210, and can reduce or eliminate the need for heat-shrink tubing and/or tape, reducing material costs and labor. The amount of radial force applied can also be varied along the length of the mandrel by, for example, varying the type or thickness of the surrounding material 210. In certain examples, multiple vessels 202 can be processed in a single fixture, and/or multiple sheaths can be processed within a single vessel 202. The apparatus 200 can also be used to produce other devices, such as shafts or catheters.
In one specific method, the sheath 100 can be formed by placing layers 102, 104, 106, 108 on the mandrel 118 and placing the mandrel with the layers inside of the vessel 202 with the thermally-expandable material 210 surrounding the outermost layer 108. If desired, one or more inner layers 120 of ePTFE (or similar material) and one or more outer layers 122 of ePTFE (or similar material) can be used (as shown in
Referring to
Referring to
The vessel dilator 300 can include a variety of active and/or passive mechanisms for engaging and retaining the sheath 100. For example, in certain examples the retaining member 306 can comprise a polymeric heat-shrink layer that can be collapsed around the distal end portion of the sheath 100. In the examples illustrated in
Referring to
Referring to
In another examples, an expandable sheath configured as described above can further comprise a shrinkable polymeric outer cover, such as a heat-shrink tubing layer 400 shown in
In some examples, the heat-shrink tubing layer 400 can extend distally beyond the distal end portion 140 of the sheath 100 as the distal overhang 408 shown in
In some examples, the heat-shrink tubing layer 400 can be configured to split open as a delivery apparatus such as the delivery apparatus 10 is advanced through the sheath 100. For example, the heat-shrink tubing layer 400 can comprise one or more longitudinally extending openings, slits, or weakened, elongated scorelines 406 such as those shown in
In other examples, splitting or tearing of the heat-shrink tubing layer 400 may be induced in a variety of other ways, such as by forming weakened areas on the tubing surface by, for example, applying chemical solvents, cutting, scoring, or ablating the surface with an instrument or laser, and/or by decreasing the wall thickness or making cavities in the tubing wall (e.g., by femto-second laser ablation).
In some examples, the heat-shrink tubing layer may be attached to the body of the sheath by adhesive, welding, or any other suitable fixation means.
In another example, the expandable sheath 100 can have a distal end or tip portion comprising an elastic thermoplastic material (e.g., Pebax), which can be configured to provide an interference fit or interference geometry with the corresponding portion of the vessel dilator 300. In certain configurations, the outer layer of the sheath 100 may comprise polyamide (e.g., nylon) in order to provide for welding the distal end portion to the body of the sheath 100. In certain examples, the distal end portion 140 can comprise a deliberately weakened portion, scoreline, slit, etc., to allow the distal end portion 140 to split apart as the delivery apparatus 10 is advanced through the distal end portion 140.
In another examples, the entire sheath 100 could have an elastomeric outer cover that extends longitudinally from the handle to the distal end portion 140 of the sheath, optionally extending onward to create an overhang similar to overhang 408 shown in
In another example, the distal end portion 140 of the expandable sheath 100 can comprise a polymer such as Dyneema®, which can be tapered to the diameter of the vessel dilator 300. Weakened portions such as dashed cuts, scoring, etc., can be applied to the distal end portion 140 such that it will split open and/or expand in a repeatable way.
Crimping of the expandable sheath 100 examples described herein can be performed in a variety of ways, as described above. In additional examples, the sheath 100 can be crimped using a conventional short crimper several times longitudinally along the longer sheath 100. In other examples, the sheath 100 may be collapsed to a specified crimped diameter in one or a series of stages in which the sheath is wrapped in heat-shrink tubing and collapsed under heating. For example, a first heat shrink tube can be applied to the outer surface of the sheath 100, the sheath 100 can be compressed to an intermediate diameter by shrinking the first heat shrink tube (via heat), the first heat shrink tube can be removed, a second heat shrink tube can be applied to the outer surface of the sheath 100, the second heat shrink tube can be compressed via heat to a diameter smaller than the intermediate diameter, and the second heat shrink tube can be removed. This can go on for as many rounds as necessary to achieve the desired crimped sheath diameter.
Crimping of the various expandable sheath examples described herein can be performed in a variety of ways, as described above. A roller-based crimping mechanism 602, such as the one shown in
Each disc-shaped roller 606 is held in place in the radially arranged configuration by a connector 608 that is attached to crimping mechanism 602 via one or more fasteners 619, such that the location of each of the plurality of connectors is fixed with respect to the first end surface of the crimping mechanism 602. In the depicted example, fasteners 619 are positioned adjacent an outer portion of the crimping mechanism 602, radially outwardly of the disc-shaped rollers 606. Two fasteners 619 are used to position each connector 608 in the example shown, but the number of fasteners 619 can vary. As shown in
During use, an elongated sheath is advanced from the first side 604 of the crimping mechanism 602, through the axial passage between the rollers, and out the second side 605 of the crimping mechanism 602. The pressure from the circular edge 610 of the disc shaped rollers 606 reduces the diameter of the sheath to a crimped diameter as it rolls along the outer surface of the elongated sheath.
The first tapered portion 713 of the narrowing lumen 714 opens toward a second end piece 711 of the holding mechanism 708, such that the widest side of the taper is located on an inner surface 722 of the first end piece 710. In the example shown, the first tapered portion 713 narrows to a narrow end 715 that connects with a narrow cylindrical portion 716 of the narrowing lumen 714. In this example, the narrow cylindrical portion 716 defines the narrowest diameter of the narrowing lumen 714. The cylindrical end portion 724 of the mandrel 706 may nest loosely within the narrow cylindrical portion 716 of the narrowing lumen 714, with enough space or clearance between the cylindrical end portion 724 and the narrow cylindrical portion 716 of the lumen to allow for passage of the elongated sheath. The elongated nature of the narrow cylindrical portion 716 may facilitate smoothing of the crimped sheath after it has passed over the conical end portion 712 of the mandrel. However, the length of the cylindrical portion 716 of the narrowing lumen 714 is not meant to limit the disclosure, and in some examples, the crimping mechanism 702 may only include first tapered portion 713 of the narrowing lumen 714, and still be effective to crimp an elongated sheath.
At the opposite end of the first end piece 710 shown in
The holding mechanism 708 further includes a second end piece 711 positioned opposite the elongated base 704 from the first end piece 710. The second end piece 711 is movable with respect to elongated base 704, such that the distance between the first end piece 710 and the second end piece 711 is adjustable and therefore able to support mandrels of varying sizes. In some examples, elongated base 704 may include one or more elongated sliding tracks 728. The second end piece 711 can be slidably engaged to the sliding track 728 via at least one reversible fastener 730, such as, but not limited to, a bolt that extends into or through the second end piece 711 and the elongated sliding track 728. To move the second end piece 711, the user would loosen or remove the reversible fastener 730, slide the second end piece 711 to the desired location, and replace or tighten the reversible fastener 730.
In use, a sheath in an uncrimped diameter can be placed over the elongated mandrel 706 of the crimping device 700 shown in
In some examples, the crimping mechanism 602 shown in
The distal end portion 902 may have a smaller collapsed diameter than the more proximal portions of the sheath, giving it a tapered appearance. This smooths the transition between the introducer/dilator 908 and the sheath 100, ensuring that the sheath 100 does not get lodged against the tissue during insertion into the patient. The smaller collapsed diameter can be a result of multiple folds (for example, 1, 2, 3, 4, 5, 6, 7, or 8 folds) positioned circumferentially (evenly or unevenly spaced) around the distal end portion. For example, a circumferential segment of the distal end portion 902 can be brought together and then laid against the adjacent outer surface of the distal end portion 902 to create an overlapping fold. In the collapsed configuration, the overlapping portions of the fold extend longitudinally along the distal end portion 902. Exemplary folding methods and configurations are described in U.S. application Ser. No. 14/880,109 (issued as U.S. Pat. No. 10,792,471) and U.S. application Ser. No. 14/880,111 (issued as U.S. Pat. No. 10,327,896), each of which are hereby incorporated by reference in their entireties. Scoring can be used as an alternative, or in addition to folding of the distal end portion 902. Both scoring and folding of the distal end portion 902 allow for the expansion of the distal end portion 902 upon the passage of the delivery system, and ease the retraction of the delivery system back into the sheath 100 once the procedure is complete. In some examples, the distal end portion 902 of the sheath 100 (and/or of the vessel dilator) can decrease from the initial diameter of the sheath (e.g., 8 mm) to 3.3 mm (10F), and may decrease to the diameter of a guide wire, allowing the sheath 100 and/or the vessel dilator 300 to run on a guide wire.
In some examples, a distal end portion 902 can be added, the sheath 100 and tip can be crimped, and the crimping of the distal end portion 902 and sheath 100 can be maintained, by the following method. As mentioned above, the distal end portion 902 can be an extension of the outer layer of the sheath 100. It can also be a separate, multilayer tubing that is heat bonded to the remainder of the sheath 100 prior to the tip crimping processing steps. In some examples, the separate, multilayer tubing is heat bonded to a distal extension of the outer layer of the sheath 100 to form the distal end portion 902. For crimping of the sheath 100 after tip attachment, the sheath 100 is heated on small mandrel. The distal end portion 902 can be folded around the mandrel to create the folded configuration shown in
This method advantageously avoids risks that a tear initiated at a score or split line (such as perforation 813 shown in
The crimping of the inner and outer polymeric layers (e.g., inner and outer layers 513, 517) and the external covering layer (e.g., layer 561) can be, for example, from a pre-compressed diameter of about 8.3 mm to a compressed diameter of about 3 mm.
The method of compressing the distal portion of the expandable sheath can further include a step of covering the expandable sheath 501 and the external covering layer 561 with a heat-shrink tube (HST) prior to, during or following the heating to the second temperature, wherein the second temperature further acts to shrink the HST in order to retain the external covering layer 561 and the expandable sheath 501 in a compressed state. The HST can be removed from the expandable sheath 501 and the external covering layer 561 after the folds 563 of the covering layer 563 are sufficiently attached to each other in the desired compressed state, and cooled down for a sufficient period of time.
According to some examples, the HST is further utilized as a heat shrink tape, to apply the external radial pressure by wrapping and heating it over the external covering layer 561 and the expandable sheath 501. According to some examples, a non heat-shrink tape can be used instead of a heat shrink tube.
The external covering layer 561 is chosen such that its melting temperature TM1 is lower than the melting temperature TM2 of the polymeric layers of the expandable sheath 100, in order to promote folds 563 formation with moderate attachment in the external covering layer 561, while avoiding melting and attaching similar folds in the polymeric layers 513 and 517 of the expandable sheath 501.
According to some examples, the external covering layer 561 is low density polyethylene. Other suitable materials as known in the arts, such as polypropylene, thermoplastic polyurethane, and the like, may be utilized to form the external covering layer 561.
According to some examples, the external covering layer 561 is attached different attachment regions, such as along a longitudinally oriented attachment line, to the external surface of the expandable sheath 501 (e.g., the outer polymeric layer). According to some examples, the external covering layer 561 is attached to the external surface of the expandable sheath 501 by a plurality of circumferentially spaced attachment regions 569, 571, wherein the circumferential distance between adjacent attachment regions is chosen to allow formation of folds 573 there between. Attachment regions 569, 571 ensure that the external covering layer 561 always remains attached to the expandable sheath 501, either during the compressed or expanded states thereof.
According to some examples, the covering with an external covering layer 561 is performed after crimping the expandable sheath 501, such that the external layer 561 covers pre-formed folds of inner 513 and/or outer 517 layers of the sheath 501.
According to some examples, the bond between the folds 563 is based on adhesive with moderate adhesion strength.
Examples of the sheaths described herein may comprise a variety of lubricious outer coatings, including hydrophilic or hydrophobic coatings, and/or surface blooming additives or coatings.
In other examples, the scorelines 504 can be configured as openings or cutouts having various geometrical shapes, such as rhombuses, hexagons, etc., or combinations thereof. In the case of hexagonal openings, the openings can be irregular hexagons with relatively long axial dimensions to reduce foreshortening of the sheath when expanded.
The sheath 500 can further comprise an outer layer (not shown), which can comprise a relatively low durometer, elastic thermoplastic material (e.g., Pebax, polyurethane, etc.), and which can be bonded (e.g., by adhesive or welding, such as by heat or ultrasonic welding, etc.) to the inner nylon layer. Attaching the outer layer to the inner layer 502 can reduce axial movement of the outer layer relative to the inner layer during radial expansion and collapse of the sheath. The outer layer may also form the distal tip of the sheath.
The expandable sheath 601 is configured for advancement in a pre-compressed state up to a target area, for example along the abdominal aorta or the aortic bifurcation, at which point the clinician should cease further advancement thereof and introduce the DS through its lumen, to facilitate expansion thereof. For that end, the clinician should receive a real-time indication of the expandable sheath's position during advancement thereof. According to an aspect of the present disclosure, there is provided at least one radio-opaque marker at or along at least one region of the expandable braided layer 621, configured to enable visualization of the expandable sheath's position under radio fluoroscopy.
According to one example, at least one of the distal crowns 633 comprises a radio-opaque marker. According to some examples, the distal crowns 633 comprise at least one gold-plated crown 635 (
Since the expandable sheath 601 comprises an expandable braided layer 621 having a plurality of crossing struts 623 disposed along its length, this structure can be advantageously utilized for more convenient incorporation of radio-opaque elements.
According to some examples, the struts 623 further comprise at least one radio-opaque strut 625, having a radio-opaque core. For example, a drawn filled tubing (DFT) wire comprising a gold core (as may be provided by, for example, Fort Wayne Metals Research Products Corp.) may serve as a radio-opaque strut 625.
Since radio-opaque wires, such as a DFT wire, can be costly, the expandable braided layer 621 can comprise a plurality of non radio-opaque or less radio-opaque struts 623, for example made of a shape-memory alloy such as Nitinol and polymer wire such as PET respectively, intertwined with at least one radio-opaque strut 625 (
According to some examples, radio-opaque wires are embedded within the polymer braid, such as the outer polymeric layer 617 or the inner polymeric layer 615, which are made of less-opaque materials.
Advantageously, the expandable braid embedded within the expandable sheath is utilized according to the present disclosure, for incorporating radio-opaque markers along specific portions thereof to improve visualization of the sheath's position in real-time under radio fluoroscopy.
According to yet another aspect of the present disclosure, radiopaque tubes can be threaded on the distal crowns or loops 633, or radiopaque rivets can be swaged on the distal crowns or loops 633 to improve their visibility under fluoroscopy.
In order to mitigate uneven surface formations, cushioning polymeric layers 61a, 61b are added between the inner 31 and outer 41 layers of the sheath 11, configured to evenly spread the forces acting in the radial direction during sheath compression. A first cushioning layer 61a is placed between the inner polymeric layer 31 and the braided layer 21, and a second cushioning layer 61b is placed between the outer polymeric layer 41 and the braided layer 21.
The cushioning layers 61a, 61b can comprise a porous material having plurality of micropores of nanopores 63 (
However, when cushioning layers comprise a plurality of micropores of nanopores 63 (
While advantageous for the reasons described above, the addition of the cushioning and sealing can increase the complexity and time required to assemble the sheath 11. Advantageously, providing a single sealed cushioning member, configured to provide both cushioning and sealing functionalities (instead of providing two separate cushioning and sealing layers, each configured to provide one functionality) reduces sheath assembly time and significantly simplifies the process. According to an aspect of the present disclosure, there is provided a single sealed cushioning member, configured for placement between the inner and outer polymeric layers of the sheath and the central braided layer. The single sealed cushioning member includes cushioning layer and a sealed surface configured to prevent leakage/melting into the pores in the radial direction.
According to another aspect of the present disclosure, and as mentioned above with respect to
Thus, there is provided an expandable sheath for deploying a medical device, comprising a first polymeric layer, a braided layer radially outward of the first polymeric layer, and a second polymeric layer radially outward of the braided layer. The braided layer includes a plurality of filaments braided together. The second polymeric layer is bonded to the first polymeric layer such that the braided layer is encapsulated between the first and second polymeric layers. When a medical device is passed through the sheath, the diameter of the sheath expands from a first diameter to a second diameter around the medical device, while the first and second polymeric layers resist axial elongation of the sheath such that the length of the sheath remains substantially constant. However, according to some examples, the first and second polymeric layers are not necessarily configured to resist axial elongation.
According to another aspect of the present disclosure, the expandable sheath does include an elastic layer. But, unlike elastic layer 106 shown in
In another optional example, the elastic layer can be applied by dip coating in an elastic material (such as, but not limited to) silicone or TPU. The dip coating can be applied to the polymeric outer layer, or to the braided layer.
Thus, there is provided an expandable sheath for deploying a medical device, comprising a first polymeric layer, a braided layer radially outward of the first polymeric layer, an elastic layer radially outward of the braided layer, and a second polymeric layer radially outward of the braided layer. The braided layers comprise a plurality of filaments braided together. The elastic layer is configured to provide the expandable sheath with sufficient column strength to resist buckling of spontaneous expansion due to friction forces applied thereto by a surrounding anatomical structure during the sheath's movement in an axial direction. The second polymeric layer is bonded to the first polymeric layer such that the braided layer is encapsulated between the first and second polymeric layers. When a medical device is passed through the sheath, the diameter of the sheath expands from a first diameter to a second diameter around the medical device, optionally while the first and second polymeric layers resist axial elongation of the sheath such that the length of the sheath remains substantially constant.
According to an aspect of the present disclosure, there is provided a three-layered expandable sheath, comprising an inner polymeric layer, an outer polymeric layer bonded to the inner polymeric layer and a braided layer encapsulated between the inner and outer polymeric layers, wherein the braided layer comprises an elastic coating.
In some examples, the second, outer polymeric layer 209 is bonded to the first, inner polymeric layer 203 such that the braided layer 205 and the elastic coating 207 are encapsulated between the first and second polymeric layers. Moreover, the elastic coating applied directly to the braided filaments is configured to serve the same function as that of the elastic layer 106 (that is, to apply radial force on the braided layer and the first polymeric layer).
While the example of
Alternatively, or additionally, an elastic coating can be applied to other layers of the sheath 201.
In some examples, a braided layer such as the one shown in
According to another aspect, an expandable sheath can include a braided expandable layer, attached to at least one expandable sealing layer. In some examples, the braided layer and the sealing layer are the only two layers of the expandable sheath. The braided layer is passively or actively expandable relative to a first diameter, and the at least one expandable sealing layer is passively or actively expandable relative to a first diameter. An expandable sealing layer can be useful with any of the examples described above, and may be particularly advantageous for braids having self-contracting frames or filaments.
The braided layer can be attached or bonded to the expandable sealing layer along its entire length, advantageously decreasing the risk of the polymeric layer being peeled off the braided layer due to frictional forces that may be applied thereon either during entry or exit through the surgical incision. The at least one sealing layer can comprise a lubricious, low-friction material, to facilitate passage of the sheath within the blood vessels, and or to facilitate passage of the delivery apparatus carrying a valve through the sheath.
A sealing layer is defined as a layer which is not permeable to the blood flow. The sealing layer can comprise a polymeric layer, a membrane, a coating and/or a fabric, such as a polymeric fabric. According to some examples, the sealing layer comprises a lubricious, low-friction material. According to some examples, the sealing layer is radially outward to the braided layer, to facilitate passage of the sheath within the blood vessels. According to some examples, the sealing layer is radially inward to the braided layer, to facilitate passage of the medical device through the sheath.
According to some examples, the at least one sealing layer is passively expandable and/or contractible. In some examples, the sealing layer is thicker at certain longitudinal positions of the sheath than at others, which can hold a self-contracting braided layer open at a wider diameter than at other longitudinal positions where the sealing layer is thinner.
Attaching the braided layer to at least one expandable sealing layer, instead of encapsulating it between two polymeric layers bonded to each other, may simplify manufacturing process and reduce costs.
According to some examples, the braided layer can be attached to both an outer expandable sealing layer and an inner expandable sealing layer, so as to seal the braided layer from both sides, while facilitating passage of the sheath along the blood vessels, and facilitating passage of a medical device within the sheath. In such examples, the braided layer can be attached to a first sealing layer, while the other sealing layer may be also attached to the first sealing layer. For example, the braided layer and the inner sealing layer can be each attached to the outer sealing layer, or the braided layer and the outer sealing layer can be each attached to the inner sealing layer.
According to some examples, the braided layer is further coated by a sealing coating. This may be advantageous in configurations of a braided layer being attached only to a single expandable layer, wherein the coating ensures that the braided layer remains sealed from the blood flow or other surrounding tissues, even along regions which are not covered by the expandable layer. For example, if a braided layer is attached to a sealing layer on one side, the other side of the braided layer may receive a sealing coating. In some examples, the sealing coating can be used instead of, or in addition to, one or both of the sealing layers.
In another example, the sheath 100 can include a folded inner and outer layer construction. Example sheaths are described for example in U.S. application Ser. No. 12/249,867 filed Oct. 10, 2008 (issued as U.S. Pat. No. 8,690,936), U.S. application Ser. No. 13/312,739 file Dec. 6, 2011 (issued as U.S. Pat. No. 8,790,387), the disclosures of which are incorporated herein by reference in their entirety.
In this manner, the sheath 100 is configured to expand from a resting configuration (
The sheath 100 can be configured such that it locally expands at a particular location corresponding to the location of the medical device along the length of the lumen 112, and then locally contracts once the medical device has passed that particular location. Thus, a bulge may be visible, traveling longitudinally along the length of the sheath as a medical device is introduced through the sheath, representing continuous local expansion and contraction as the device travels the length of the sheath 100. In some examples, each segment of the sheath 100 can locally contract after removal of any radial outward force such that it regains the original resting diameter of lumen 112. In some examples, each segment of the sheath 100 can locally contract after removal of any radial outward force such that it at least partially returns to the original resting diameter of lumen 112.
It is contemplated that an expandable introducer can be used with any of the sheath examples described herein. As described above, the various sheath examples can include a distal tip formed from multiple layers of material and/or folded layers treated with compression or heating. As a result, the distal tip of the sheath may be narrower and/or stiffer than the remaining portions of the sheath. Accordingly, an expandable introducer may be used to facilitate expansion of the distal tip of the sheath/pre-dilate the sheath tip, proving more room for delivery and withdraw of medical equipment through the distal opening of the sheath. Accordingly, we are able to reduce the push force needed for delivery and provide an opening large enough to retrieve medical equipment without causing trauma to the patient and/or damage to the sheath.
As illustrated in
The balloon 164 is inflatable from an unexpanded configuration (
The introducer 160 is both axially/longitudinally and rotatably movable within the central lumen 112. As illustrated in
The inflated balloon 164 can have any regular and irregular shape.
The balloon 164 can be constructed from a compliant material, a semi-compliant material, and/or a non-compliant material. For example, when the balloon 164 is composed of a compliant material, the balloon 164 may be constructed from a polyamide, polyolefin, silicone, and/or polyester. In some examples, the polyamide can be nylon. In some examples the polyolefin can be polyethylene or polypropylene. In some examples, the polyester can be polyethylene terephthalate (PET). Balloon 164 is may also be constructed from a polymeric material. Different portions of the balloon 164 may be composed of different materials, e.g., a compliant material, semi-compliant material, and/or non-compliant material. For example, a proximal portion of the balloon 164 can be composed of a less compliant material than a distal portion of the balloon 164, where the proximal portion of the balloon is adjacent the proximal end 166 of the elongated body member 162 and the distal portion of the balloon 164 is adjacent the distal end 168 of the elongated body member 162.
The balloon 164 can also be composed of an impermeable material for containing the inflation fluid, for example saline, within the balloon 164. In some examples, the inflation fluid can also include a contrast medium. The balloon 164 can also be composed of a permeable material such as a mesh or perforated material. In this example, the permeable material allows for fluid communication between an interior of the balloon 164 and an exterior of the balloon. The inflation fluid is provided to the interior of the balloon 164 via the inflation lumen 170. The inflation lumen 170 extends longitudinally within the elongated body portion 162 of the introducer 160 between a reservoir for the inflation fluid and the interior of the balloon 164. The volume of the inflation fluid can be varied to control the volume/inflation of the balloon 164. Where the balloon 164 is permeable, the flow rate of inflation fluid into the balloon 164 and through the mesh material can be varied to control the inflation of the balloon 164. Additionally, the flow rate of the inflation fluid can be controlled is such that the balloon 164 inflates to a diameter greater than the outer diameter of the elongated body member 162, even while inflation fluid is passing through the mesh material.
The balloon 164 can have a uniform wall thickness along the length and/or around the circumference of the balloon 164. In another example, the wall thickness of the balloon 164 varies along the length and/or around the circumference of the balloon 164. For example, the wall thickness of the proximal portion of the balloon 164 can be greater than the thickness of the distal portion of the balloon 164, the proximal portion of the balloon 164 adjacent the proximal end 166 of the elongated body member 162 and the distal portion of the balloon 164 is adjacent the distal end 168 of the elongated body member 162. In an alternate example, the thickness of the distal portion of the balloon 164 is greater than the thickness of the proximal portion of the balloon 164. In a further example, the balloon 164 includes at least one circumferential band of increased wall thickness.
As illustrated in
The method of expanding the distal end portion 140 of the sheath 100 during delivery of a medical device is described below.
Typically, a guide wire is advanced into the patient's vasculature to the treatment site. With the sheath 100 and the introducer 160 coupled, the sheath 100 and introducer 160 are advanced along the guide wire to the treatment site. The guidewire can remain in place during expansion of the distal end portion 140 of the sheath 100 or it can be removed. The position of the sheath 100 and/or the introducer 160 can be imaged as it is moved through the patient's vasculature using an imaging modality such as x-ray fluoroscopy. The introducer 160 can include a radio opaque marker(s) to determine the position of the introducer 160.
Once the sheath 100 is at the desired position, the introducer 160 is advanced axially/longitudinally within the central lumen of the sheath 100 such that an inflatable balloon 164 is axially aligned with a distal opening of the sheath 100, as shown in
Next, as illustrated in
Next the balloon 164 is deflated as the inflation fluid is removed from the interior of the balloon 164. For example, the inflation fluid can be withdrawn from the balloon 164 via mechanical suction or vacuum. In another example, were the balloon 164 comprises a mesh material, the flow of inflation fluid into the balloon 164 can end, causing the balloon to deflate. With the balloon 164 deflated, the diameter of the balloon 164 is less than the second/inflated diameter of the balloon 164 and approaches the initial/non-inflated diameter of the balloon 164. The introducer 160 is then withdrawn through the central lumen 112 of the sheath 100 and the distal end portion 140 of the sheath 100 remains expanded after the introducer 160 has been withdrawn.
With the central lumen 112 free of the introducer 160, the medical device 12 can be advanced through the sheath 100 to the treatment site. When advancing the medical device 12 through the central lumen 112 of the sheath 100, the medical device 12 applies an outward radial force on an inner surface of the central lumen 112. This outward radial force locally expands the sheath 100 from an initial non-expanded state to a locally expanded state. The diameter of the sheath 100 increases from a first (non-expanded) diameter to a second, larger (expanded) diameter. In some examples described above, the sheath 100 includes a polymeric layer having at least one longitudinally-extending fold when the sheath 100 is at the first (non-expanded) diameter. The medical device 12 passing through the central lumen 112 of the sheath 100 applies an outward radial force on the sheath 100 causing the sheath 100 to expand radially by at least partially unfolding the longitudinally-extending fold(s). In some examples, partial unfolding of the longitudinally-extending fold(s) causes a decrease in a wall thickness of the introducer sheath 100. Similarly, in some examples described above, the sheath 100 includes a polymeric layer having a plurality of longitudinally-extending folds when the sheath 100 is at the first (non-expanded) diameter. The longitudinally-extending folds creating a plurality of circumferentially spaced ridges and a plurality of circumferentially spaced valleys. The medical device 12 passing through the central lumen 112 of the sheath 100 applies an outward radial force on the sheath 100 causing the sheath 100 to expand radially from the first (non-expanded) diameter to the second, larger (expanded) diameter by levelling out the ridges and valleys. Preferably, the medical device 12 is advanced through the sheath 100 at a push for less than the push force required for a sheath with a non-expanded tip.
Once the medical device 12 has passed, the sheath 100 locally contracts from the locally expanded state at least partially back to the non-expanded state after passage of the medical device 12. In some examples, the sheath 100 includes a layer of a self-contracting material to facilitate local contraction of the sheath.
As illustrated in
It is further contemplated that the introducer sheaths 100 described herein can be used in combination with an expansion device 1000. Example expansion devises 1000 are illustrated in
As described above, the expansion device 1000 is received within the central lumen 112 of the sheath 100. As illustrated in
For example, the body 1010 includes a body diameter DB and the protrusion 1020 includes a protrusion diameter DP, and the protrusion diameter DP is greater than the body diameter DB. In some examples, the body diameter DB is 14F, and the diameter DP is greater than 14F. In other examples, the body diameter is 2F, and the protrusion diameter is greater than 2F. In other examples, the body diameter is 4F, and the protrusion diameter is greater than 4F. In other examples, the body diameter is 6F, and the protrusion diameter is greater than 6F. In other examples, the body diameter is 8F, and the protrusion diameter is greater than 8F. In other examples, the body diameter is 10F, and the protrusion diameter is greater than 10F. In other examples, the body diameter is 12F, and the protrusion diameter is greater than 12F. In other examples, the body diameter is 16F, and the protrusion diameter is greater than 16F. In other examples, the body diameter is 18F, and the protrusion diameter is greater than 18F. In other examples, the body diameter is 20F, and the protrusion diameter is greater than 20F. In other examples, the body diameter is 22F, and the protrusion diameter is greater than 22F. In other examples, the body diameter is 24F, and the protrusion diameter is greater than 24F. In other examples, the body diameter is 26F, and the protrusion diameter is greater than 26F. In other examples, the body diameter is 28F, and the protrusion diameter is greater than 28F. In other examples, the body diameter is any suitable diameter as long as the protrusion diameter is greater than the body diameter.
The protrusion 1020 can be fixedly disposed at a location along the length of the body 1010. For example, the protrusion 1020 can be fixedly coupled to and/or integrally formed with the body 1010. In some examples, the protrusion 1020 is molded to or otherwise integrally formed with the body 1010. In further examples, the protrusion 1020 is fixedly coupled to the body 1010 through an adhesive, a chemical or mechanical fastener, and or heat processing (e.g., welding).
The protrusion 1020 can have any regular or irregular shape. The protrusion 1020 can have any shape similar to the balloon 164 shapes illustrated in
As illustrated in
Both the body 1010 and the protrusion 1020 further include an outer surface 1018, 1028. In some examples, the outer surface 1018 of the body 1010 and the outer surface 1028 of the protrusion 1020 include a hydrophilic coating to reduce friction between the sheath 100 and the expansion device 1000 and ensure that the expansion device 1000 is easily received and movable within the central lumen of the expandable sheath 100. In some examples, the hydrophilic coating includes a material with a low coefficient of friction.
In another example, as shown in
The locking mechanism 1030 is disposed along the proximal end 1012 of the body 1010 and is larger than the body diameter DB. In some implementations, the locking mechanism 1030 is adjustably disposable along a portion of the body such that a user is able to adjust the distance between the protrusion 1020 and the locking mechanism 1030, thereby adjusting how far the protrusion 1020/expansion device 1000 moves within the expandable sheath 100. As a result, the locking mechanism 1030 prevents the user from inserting the expansion device 1000 (and protrusion 1020) too deep within the expandable sheath 100 and helps to avoid unnecessary trauma to a patient's vascular system.
In the example shown in
As described above, the expansion device 1000 can be used as a dilator to dilate/expand the sheath 100 and corresponding portion of the patient's blood vessel in advance of the insertion of the delivery device.
As described above, the protrusion 1020 can axially and/or rotationally fixed to a certain position along/around the body 1010 of the expansion device. It is further contemplated that the axial and rotational position of the protrusion 1020 can be adjusted along/around the body 1010. For example, protrusion 1020 can include an adjustment device capable are fixedly coupling the protrusion 1020 at varying locations longitudinally and circumferentially along/around the body 1010. For example, the protrusion 1020 can include a threaded portion for engaging a corresponding threaded portion on the body 1010. In one example, the protrusion 1020 includes a central lumen/throughhole including a threaded inner surface. Likewise, the outer surface of the body 1010 can include a threaded outer surface extending along all or a portion of the outer surface of the body 1010. The threaded opening provided on the protrusion 1020 can engage the threads provided on the outer surface of the body 1010 such that the protrusion 1020 is rotationally adjustable around the body 1010 and, thus, axially movably along the body 1010 by engagement between the threaded portions. In other implementations, the protrusion 1020 is adjustably disposed on the body 1010 and includes a locking mechanism (e.g., a mechanical fastener including, for example, a pin, screw, bolt, clip, bayonet lock, or any other mechanical fastener suitable for fixing the protrusion 1020 with respect to the body 1010) for fixing the axial and rotational position of the protrusion 1020 along the body 1010.
Each of the expandable sheaths 100 shown in
A method of locally expanding an expandable sheath using an expansion device is disclosed herein. In this example, the combined sheath and expansion device can be used as an introducer. The method includes introducing an expansion device within a central lumen of the expandable sheath. The combined expandable sheath and expansion device are then advanced into a patient's vascular. The expansion device is advanced distally within the central lumen of the expandable sheath to locally expand the lumen of the sheath at a local axial location corresponding to an axial location of a radially extending protrusion provided on the expansion device.
Introducing the expansion device within the central lumen of the expandable sheath also includes positioning the expansion device within the central lumen of the sheath such that the radially extending protrusion is disposed proximally (outside of) the strain relief portion of the sheath. In another example, introducing the expansion device within the central lumen of the expandable sheath includes positioning the expansion device within the central lumen of the sheath such that the protrusion is at least partially disposed within the strain relief portion of the expandable sheath.
In some examples, locally expanding the lumen of the sheath further includes advancing the expansion device through the strain relief portion of the sheath and into an elongated body portion of the sheath. The expansion device can then be advanced beyond the strain relief portion of the sheath and into an elongated body portion of the sheath.
The method next includes removing the expansion device from the expandable sheath such that the outer diameter of the sheath (and inner diameter of the central lumen of the sheath) corresponding to the location(s) of the protrusion is greater than the non-expanded, initial, diameter of the sheath.
Lastly, the method includes inserting a medical device into the central lumen of the expandable sheath.
Another method of locally expanding an expandable sheath using an expansion device is disclosed herein. In this example, the sheath and expansion device can be used as a dilator to pre-dilate/expand the sheath and the patient's vasculature. The method includes introducing an expandable sheath having a central lumen into a patient's vascular. The expansion device is advanced into the central lumen of the expandable sheath. The expansion device is advanced distally within the central lumen of the expandable sheath to locally expand the lumen of the sheath at an (local) axial location corresponding to the axial location of the radially extending protrusion provided on the expansion device.
Introducing an expansion device within the central lumen of the expandable sheath can further include positioning the expansion device within the central lumen of the sheath such that the radially extending protrusion is at least disposed within a strain relief portion of the expandable sheath.
In some examples, locally expanding the lumen of the sheath further includes advancing the expansion device beyond the strain relief portion of the sheath and into an elongated body portion of the sheath.
The method next includes removing the expansion device from the expandable sheath such that the outer diameter of the sheath (and inner diameter of the central lumen of the sheath) corresponding to the location(s) of the protrusion is greater than the non-expanded, initial, diameter of the sheath. Lastly, the method includes inserting a medical device into the central lumen of the expandable sheath.
General Considerations
For purposes of this description, certain aspects, advantages, and novel features of the examples of this disclosure are described herein. The disclosed methods, apparatus, and systems should not be construed as being limiting in any way. Instead, the present disclosure is directed toward all novel and nonobvious features and aspects of the various disclosed examples, alone and in various combinations and sub-combinations with one another. The methods, apparatus, and systems are not limited to any specific aspect or feature or combination thereof, nor do the disclosed examples require that any one or more specific advantages be present or problems be solved.
Although the operations of some of the disclosed examples are described in a particular, sequential order for convenient presentation, it should be understood that this manner of description encompasses rearrangement, unless a particular ordering is required by specific language set forth below. For example, operations described sequentially may in some cases be rearranged or performed concurrently. Moreover, for the sake of simplicity, the attached figures may not show the various ways in which the disclosed methods can be used in conjunction with other methods. Additionally, the description sometimes uses terms like “provide” or “achieve” to describe the disclosed methods. These terms are high-level abstractions of the actual operations that are performed. The actual operations that correspond to these terms may vary depending on the particular implementation and are readily discernible by one of ordinary skill in the art.
As used in this application and in the claims, the singular forms “a,” “an,” and “the” include the plural forms unless the context clearly dictates otherwise. Additionally, the term “includes” means “comprises.” Further, the terms “coupled” and “associated” generally mean electrically, electromagnetically, and/or physically (e.g., mechanically or chemically) coupled or linked and does not exclude the presence of intermediate elements between the coupled or associated items absent specific contrary language.
In the context of the present application, the terms “lower” and “upper” are used interchangeably with the terms “inflow” and “outflow”, respectively. Thus, for example, the lower end of a valve is its inflow end and the upper end of the valve is its outflow end.
As used herein, the term “proximal” refers to a position, direction, or portion of a device that is closer to the user and further away from the implantation site. As used herein, the term “distal” refers to a position, direction, or portion of a device that is further away from the user and closer to the implantation site. Thus, for example, proximal motion of a device is motion of the device toward the user, while distal motion of the device is motion of the device away from the user. The terms “longitudinal” and “axial” refer to an axis extending in the proximal and distal directions, unless otherwise expressly defined.
Unless otherwise indicated, all numbers expressing dimensions, quantities of components, molecular weights, percentages, temperatures, forces, times, and so forth, as used in the specification or claims, are to be understood as being modified by the term “about.” Accordingly, unless otherwise indicated, implicitly or explicitly, the numerical parameters set forth are approximations that can depend on the desired properties sought and/or limits of detection under test conditions/methods familiar to those of ordinary skill in the art. When directly and explicitly distinguishing examples from discussed prior art, the example numbers are not approximates unless the word “about” is recited. Furthermore, not all alternatives recited herein are equivalents.
In view of the many possible examples to which the principles of the disclosed technology may be applied, it should be recognized that the illustrated examples are only preferred examples and should not be taken as limiting the scope of the disclosure. Rather, the scope of the disclosure is at least as broad as the following claims. We therefore claim all that comes within the scope and spirit of these claims.
Example 1: An expandable introducer comprising: an elongated body member; an inflatable balloon disposed between a proximal and distal end of the elongated body member, the balloon expandable from a deflated configuration to an inflated configuration; and an inflation lumen in fluid communication with the inflatable balloon, the inflation sized and configured for providing an inflation fluid to the balloon; wherein, in the deflated configuration, an outer diameter of the balloon corresponds to an outer diameter of the elongated body member, and in the inflated configuration, the outer dimeter of the balloon is greater than the outer diameter of the elongated body member, wherein at least a portion of the balloon is sized and configured to pass through a distal opening of an expandable introducer sheath when the balloon is in the deflated condition, the balloon sized and configured to expand at least a portion of a distal end of an introducer sheath as the balloon is inflated.
Example 2: The expandable introducer according to any example herein, particularly example 1, including an expandable introducer sheath for deploying a medical device, wherein the elongated body member is received within a central lumen of the introducer sheath, and axially and rotatably movable therein.
Example 3: The expandable introducer according to any example herein, particularly example 2, wherein the elongated body member is movable through a distal opening provided in the introducer sheath.
Example 4: The expandable introducer according to any example herein, particularly example 3, wherein during insertion into the patient's vasculature, at least a portion of an outer surface of the elongated body member is fitted against a surface of the central lumen of the introducer sheath proximate the distal opening.
Example 5: The expandable introducer according to any example herein, particularly example 4, wherein the elongated body member is fitted against the surface of the central lumen by at least one of a press fit and an interference fit.
Example 6: The expandable introducer according to any example herein, particularly examples 1-5, wherein axial movement of the elongated body member through the distal opening is limited such that when the elongated body member is provided in a distal-most position, the balloon is aligned axially with the distal opening of the introducer sheath.
Example 7: The expandable introducer according to any example herein, particularly example 6, wherein when the elongated body member is at the distal-most position, a first portion of the balloon extends beyond the distal opening of the introducer sheath and a second portion of the balloon remains within the central lumen of the introducer sheath, wherein the second portion of the balloon is sized and configured to expand at least a portion of the distal end of the introducer sheath as the balloon expands from the deflated configuration to the inflated configuration.
Example 8: The expandable introducer according to any example herein, particularly example 7, wherein the second portion of the balloon includes a tapered surface adapted to dilate the at least a portion of the distal end of the introducer sheath to a corresponding tapered shape.
Example 9: The expandable introducer according to any example herein, particularly examples 1-8, wherein a diameter of the central lumen of the introducer sheath is greater than the diameter of the elongated body member.
Example 10: The expandable introducer according to any example herein, particularly examples 1-9, wherein a diameter of the distal opening of the introducer sheath when dilated is up to about 75% larger than a diameter of the distal opening of the introducer sheath when not dilated.
Example 11: The expandable introducer according to any example herein, particularly examples 1-10, wherein when a medical device is passed through the central lumen of the introducer sheath, a diameter of the introducer sheath expands from a first diameter to a second, larger, diameter.
Example 12: The expandable introducer according to any example herein, particularly example 11, wherein the introducer sheath includes at least one polymeric layer including a plurality of longitudinally-extending folds when the sheath is at the first diameter, wherein a medical device passing through the central lumen of the introducer sheath applies an outward radial force on the introducer sheath causing the introducer sheath to expand radially from the first diameter to the second diameter by at least partially unfolding the plurality of longitudinally-extending folds.
Example 13: The expandable introducer according to any example herein, particularly example 12, wherein the at least partial unfolding of the plurality of longitudinally-extending folds causes a decrease in a wall thickness of the introducer sheath.
Example 14: The expandable introducer according to any example herein, particularly example 11, wherein the introducer sheath includes at least one polymeric layer including a plurality of longitudinally-extending folds when the sheath is at the first diameter, the longitudinally-extending folds creating a plurality of circumferentially spaced ridges and a plurality of circumferentially spaced valleys, wherein a medical device passing through the central lumen of the introducer sheath applies an outward radial force on the introducer sheath causing the introducer sheath to expand radially from the first diameter to the second diameter by levelling out the ridges and valleys.
Example 15: The expandable introducer according to any example herein, particularly example 12, wherein the introducer sheath includes at least one layer of a self-contracting material.
Example 16: The expandable introducer according to any example herein, particularly examples 1-15, wherein the outer diameter of the elongated body member is less than a diameter of the central lumen.
Example 17: The expandable introducer according to any example herein, particularly examples 1-16, wherein the elongated body member comprises a lubricious material.
Example 18: The expandable introducer according to any example herein, particularly examples 1-17, wherein the elongated body member is flexible.
Example 19: The expandable introducer according to any example herein, particularly example 18, wherein the elongated body member composed of a flexible material including high-density polyethylene.
Example 20: The expandable introducer according to any example herein, particularly example 18, wherein the elongated body member includes a flexibility feature including at least one circumferentially and/or longitudinally extending groove, a slit, and a coil.
Example 21: The expandable introducer according to any example herein, particularly examples 1-20, wherein the distal end of the elongated body member includes a tapered tip portion adapted for insertion into a body tissue.
Example 22: The expandable introducer according to any example herein, particularly examples 1-21, wherein the introducer includes a radio opaque marker.
Example 23: The expandable introducer according to any example herein, particularly example 22, wherein the radio opaque maker is located proximate at least one of the tapered distal end of the elongated body member, along the elongated body member proximate a leading end of the balloon, on the balloon, and along the elongated body member at a trailing end of the balloon.
Example 24: The expandable introducer according to any example herein, particularly examples 1-23, including a guidewire lumen extending therethrough.
Example 25: The expandable introducer according to any example herein, particularly example 24, wherein the guidewire lumen extends along a longitudinal centerline of the elongated body member, wherein the inflation lumen is radially offset from the guidewire lumen, the inflation lumen extending along a first side of the guidewire lumen.
Example 26: The expandable introducer according to any example herein, particularly examples 1-25, wherein a shape of the balloon in the inflated configuration comprises at least one of a regular or irregular shape.
Example 27: The expandable introducer according to any example herein, particularly examples 1-26, wherein a shape of the balloon in the inflated configuration includes a tapered leading edge and a tapered trailing edge, the leading edge adjacent the distal end of the elongated body member and the trailing edge adjacent the proximal end of the elongated body member.
Example 28: The expandable introducer according to any example herein, particularly example 27, wherein the taper of the leading edge corresponds to the taper of the trailing edge.
Example 29: The expandable introducer according to any example herein, particularly example 27, wherein the taper of the leading edge is greater than the taper of the trailing edge.
Example 30: The expandable introducer according to any example herein, particularly example 27, wherein the taper of the leading edge is less than the taper of the trailing edge.
Example 31: The expandable introducer according to any example herein, particularly example 27, wherein the balloon includes a cylindrical body portion extending between the tapered leading edge and the tapered trailing edge.
Example 32: The expandable introducer according to any example herein, particularly example 27, wherein the balloon includes a tapered body portion extending between the tapered leading edge and the tapered trailing edge, wherein the taper of the body portion varies from the tapers of each of the leading and trailing edges.
Example 33: The expandable introducer according to any example herein, particularly examples 1-32, wherein a shape of the balloon in the inflated configuration comprises at least one an elliptical-shaped balloon, a spherical-shaped balloon, a square-shaped balloon, a conical-shaped balloon, an elongated spherical-shaped balloon, an elongated conical/square-shaped balloon, an elongated conical/spherical-shaped balloon, an elongated conical/conical-shaped balloon, a conical/square-shaped balloon, a tapered balloon, a stepped balloon, an offset balloon.
Example 34: The expandable introducer according to any example herein, particularly example 33, wherein the conical-shaped balloon includes a tapered leading and trailing edge, wherein the elongated spherical-shaped balloon includes an elongated cylindrical body portion and a semi-spherical-shaped leading and trailing edge, wherein the elongated conical/square-shaped balloon includes an elongated cylindrical body, a first edge tapered and a second edge square-shaped, wherein the elongated conical/spherical-shaped balloon includes an elongated cylindrical body, a first edge tapered and a second edge semi-spherical-shaped, wherein the elongated conical/conical-shaped balloon includes a tapered leading and trailing edge, wherein the conical/square-shaped balloon includes a tapered first edge and a square-shaped second edge, wherein the tapered balloon includes a tapered leading edge and a tapered trailing edge, wherein the stepped balloon includes portions of varying diameter, wherein the offset balloon includes a height on a first side of the elongated body member greater than a height on an opposite second side of the elongated body member.
Example 35: The expandable introducer according to any example herein, particularly example 1, wherein the balloon is made of polymeric material.
Example 36: The expandable introducer according to any example herein, particularly examples 1-35, wherein the balloon is composed of at least one of a compliant material, a semi-compliant material, and a non-compliant material.
Example 37: The expandable introducer according to any example herein, particularly example 36, wherein the balloon is composed of a compliant material.
Example 38: The expandable introducer according to any example herein, particularly example 37, wherein the balloon is composed of at least one of polyolefin, silicone, polyethylene terephthalate.
Example 39: The expandable introducer according to any example herein, particularly example 36, wherein different portions of the balloon are composed of different ones of the compliant material, semi-compliant material, and non-compliant material.
Example 40: The expandable introducer according to any example herein, particularly example 39, wherein a proximal portion of the balloon is composed of a less compliant material than a distal portion of the balloon, wherein the proximal portion of the balloon is adjacent the proximal end of the elongated body member and the distal portion of the balloon is adjacent the distal end of the elongated body member.
Example 41: The expandable introducer according to any example herein, particularly example 40, wherein at least a portion of the proximal portion of the balloon includes a tapered surface.
Example 42: The expandable introducer according to any example herein, particularly example 41, wherein the tapered surface sized and configured to be located adjacent a distal opening of an introducer sheath such that the tapered surface of the balloon is adapted to expand the distal end of an introducer sheath.
Example 43: The expandable introducer according to any example herein, particularly examples 1-42, wherein the balloon is composed of an impermeable material.
Example 44: The expandable introducer according to any example herein, particularly examples 1-43, wherein the balloon is composed of a permeable material.
Example 45: The expandable introducer according to any example herein, particularly example 44, wherein the balloon comprises a mesh material that allows for fluid communication between an interior of the balloon and an exterior of the balloon.
Example 46: The expandable introducer according to any example herein, particularly example 45, where if the flow rate of inflation fluid through the mesh material of the balloon is such that the balloon inflates to have a diameter greater than the outer diameter of the elongated body member.
Example 47: The expandable introducer according to any example herein, particularly examples 1-46, including an inflation fluid comprises saline.
Example 48: The expandable introducer according to any example herein, particularly examples 1-47, wherein an inflation fluid includes a contrast medium.
Example 49: The expandable introducer according to any example herein, particularly examples 1-48, wherein the balloon has a uniform thickness along a length and/or around a circumference of the balloon.
Example 50: The expandable introducer according to any example herein, particularly examples 1-49, wherein a thickness of the balloon varies along a length and/or around a circumference of the balloon.
Example 51: The expandable introducer according to any example herein, particularly example 50, wherein a thickness of a proximal portion of the balloon is greater than a thickness of a distal portion of the balloon, wherein the proximal portion of the balloon is adjacent the proximal end of the elongated body member and the distal portion of the balloon is adjacent the distal end of the elongated body member.
Example 52: The expandable introducer according to any example herein, particularly example 50, wherein a thickness of a distal portion of the balloon is greater than a thickness of a proximal portion of the balloon, wherein the proximal portion of the balloon is adjacent the proximal end of the elongated body member and the distal portion of the balloon is adjacent the distal end of the elongated body member.
Example 53: The expandable introducer according to any example herein, particularly example 50, wherein the balloon includes at least one circumferential band of increased thickness.
Example 54: The expandable introducer according to any example herein, particularly examples 1-53, wherein the balloon is coupled to the elongated body member such that there is no break between an outer surface of the elongated body member and an outer surface of the balloon.
Example 55: The expandable introducer according to any example herein, particularly examples 1-54, wherein, in the inflated configuration, the diameter of the balloon is up to about 75% larger than the diameter of the elongated body member.
Example 56: An introducer sheath system comprising: an expandable introducer sheath for deploying a medical device; an introducer received within a central lumen of the introducer sheath and axially and rotatably movable therein, the introducer comprising: an elongated body member having a proximal end and a tapered distal end; an inflatable balloon disposed between the proximal end and the distal end of the elongated body member, the balloon expandable from a deflated configuration to an inflated configuration; and an inflation lumen in fluid communication with the inflatable balloon, the inflation sized and configured for providing an inflation fluid to the balloon; wherein, in the deflated configuration, an outer diameter of the balloon corresponds to an outer diameter of the elongated body member, and in the inflated configuration, the outer dimeter of the balloon is greater than the outer diameter of the elongated body member, wherein at least a portion of the balloon is sized and configured to pass through a distal opening of the introducer sheath when the balloon is in the deflated condition, as the balloon is inflated at least a portion of the distal end of an introducer sheath expands, increasing a diameter of the distal opening.
Example 57: The introducer sheath system according to any example herein, particularly example 56, wherein the elongated body member is movable through the distal opening provided in the introducer sheath.
Example 58: The introducer sheath system according to any example herein, particularly example 57, wherein during insertion into the patient's vasculature, at least a portion of an outer surface of the elongated body member is fitted against a surface of the central lumen of the introducer sheath proximate the distal opening.
Example 59: The introducer sheath system according to any example herein, particularly example 58, wherein the elongated body member is fitted against the surface of the central lumen by at least one of a press fit and an interference fit.
Example 60: The introducer sheath system according to any example herein, particularly examples 56-59, wherein axial movement of the elongated body member through the distal opening is limited such that when the elongated body member is provided in a distal-most position, the balloon is aligned axially with the distal opening of the introducer sheath.
Example 61: The introducer sheath system according to any example herein, particularly example 60, wherein when the elongated body member is at the distal-most position, a first portion of the balloon extends beyond the distal opening of the introducer sheath and a second portion of the balloon remains within the central lumen of the introducer sheath, wherein the second portion of the balloon is sized and configured to dilate at least a portion of the distal end of the introducer sheath as the balloon expands from the deflated configuration to the inflated configuration.
Example 62: The introducer sheath system according to any example herein, particularly example 61, wherein the second portion of the balloon includes a tapered surface adapted to dilate the at least a portion of the distal end of the introducer sheath to a corresponding tapered shape.
Example 63: The introducer sheath system according to any example herein, particularly examples 56-62, wherein a diameter of the central lumen of the introducer sheath is greater than the diameter of the elongated body member.
Example 64: The introducer sheath system according to any example herein, particularly examples 56-63, wherein a diameter of the distal opening of the introducer sheath when dilated up to about 75% larger than a diameter of the distal opening of the introducer sheath when not dilated.
Example 65: The introducer sheath system according to any example herein, particularly examples 56-64, wherein when a medical device is passed through the central lumen of the introducer sheath, a diameter of the introducer sheath expands from a first diameter to a second, larger, diameter.
Example 66: The introducer sheath system according to any example herein, particularly example 65, wherein the introducer sheath includes at least one polymeric layer including a plurality of longitudinally-extending folds when the sheath is at the first diameter, wherein a medical device passing through the central lumen of the introducer sheath applies an outward radial force on the introducer sheath causing the introducer sheath to expand radially from the first diameter to the second diameter by at least partially unfolding the plurality of longitudinally-extending folds.
Example 67: The introducer sheath system according to any example herein, particularly example 66 wherein the at least partial unfolding of the plurality of longitudinally-extending folds causes a decrease in a wall thickness of the introducer sheath.
Example 68: The introducer sheath system according to any example herein, particularly examples 65-67, wherein the introducer sheath includes at least one polymeric layer including a plurality of longitudinally-extending folds when the sheath is at the first diameter, the longitudinally-extending folds creating a plurality of circumferentially spaced ridges and a plurality of circumferentially spaced valleys, wherein a medical device passing through the central lumen of the introducer sheath applies an outward radial force on the introducer sheath causing the introducer sheath to expand radially from the first diameter to the second diameter by levelling out the ridges and valleys.
Example 69: The introducer sheath system according to any example herein, particularly examples 65-68, wherein the introducer sheath includes at least one layer of a self-contracting material.
Example 70: The introducer sheath system according to any example herein, particularly examples 56-69, wherein the outer diameter of the elongated body member ranges between is less than a diameter of the central lumen of the introducer sheath.
Example 71: The introducer sheath system according to any example herein, particularly examples 56-70, wherein the elongated body member comprises a lubricious material.
Example 72: The introducer sheath system according to any example herein, particularly example 61, wherein the elongated body member is flexible.
Example 73: The introducer sheath system according to any example herein, particularly example 72, wherein the elongated body member composed of a flexible material including high-density polyethylene.
Example 74: The introducer sheath system according to any example herein, particularly example 72, wherein the elongated body member includes a flexibility feature including at least one circumferentially and/or longitudinally extending groove, a slit, and a coil.
Example 75: The introducer sheath system according to any example herein, particularly examples 56-74, wherein the distal end of the elongated body member includes a tapered tip portion adapted for insertion into a body tissue.
Example 76: The introducer sheath system according to any example herein, particularly examples 56-75, wherein the introducer includes a radio opaque marker.
Example 77: The introducer sheath system according to any example herein, particularly example 76, wherein the radio opaque maker is located proximate at least one of the tapered distal end of the elongated body member, along the elongated body member proximate a leading end of the balloon, on the balloon, and along the elongated body member at a trailing end of the balloon.
Example 78: The introducer sheath system according to any example herein, particularly examples 56-77, including a guidewire lumen extending therethrough.
Example 79: The introducer sheath system according to any example herein, particularly example 78, wherein the guidewire lumen extends along a longitudinal centerline of the elongated body member, wherein the inflation lumen is radially offset from the guidewire lumen, the inflation lumen extending along a first side of the guidewire lumen.
Example 80: The introducer sheath system according to any example herein, particularly examples 56-79, wherein a shape of the balloon in the inflated configuration comprises at least one of a regular or irregular shape.
Example 81: The introducer sheath system according to any example herein, particularly examples 56-80, wherein a shape of the balloon in the inflated configuration includes a tapered leading edge and a tapered trailing edge, the leading edge adjacent the distal end of the elongated body member and the trailing edge adjacent the proximal end of the elongated body member.
Example 82: The introducer sheath system according to any example herein, particularly example 81, wherein the taper of the leading edge corresponds to the taper of the trailing edge.
Example 83: The introducer sheath system according to any example herein, particularly example 81, wherein the taper of the leading edge is greater than the taper of the trailing edge.
Example 84: The introducer sheath system according to any example herein, particularly example 81, wherein the taper of the leading edge is less than the taper of the trailing edge.
Example 85: The introducer sheath system according to any example herein, particularly example 81, wherein the balloon includes a cylindrical body portion extending between the tapered leading edge and the tapered trailing edge.
Example 86: The introducer sheath system according to any example herein, particularly example 81, wherein the balloon includes a tapered body portion extending between the tapered leading edge and the tapered trailing edge, wherein the taper of the body portion varies from the tapers of each of the leading and trailing edges.
Example 87: The introducer sheath system according to any example herein, particularly examples 56-86, wherein a shape of the balloon in the inflated configuration comprises at least one an elliptical-shaped balloon, a spherical-shaped balloon, a square-shaped balloon, a conical-shaped balloon, an elongated spherical-shaped balloon, an elongated conical/square-shaped balloon, an elongated conical/spherical-shaped balloon, an elongated conical/conical-shaped balloon, a conical/square-shaped balloon, a tapered balloon, a stepped balloon, an offset balloon.
Example 88: The introducer sheath system according to any example herein, particularly example 87, wherein the conical-shaped balloon includes a tapered leading and trailing edge, wherein the elongated spherical-shaped balloon includes an elongated cylindrical body portion and a semi-spherical-shaped leading and trailing edge, wherein the elongated conical/square-shaped balloon includes an elongated cylindrical body, a first edge tapered and a second edge square-shaped, wherein the elongated conical/spherical-shaped balloon includes an elongated cylindrical body, a first edge tapered and a second edge semi-spherical-shaped, wherein the elongated conical/conical-shaped balloon includes a tapered leading and trailing edge, wherein the conical/square-shaped balloon includes a tapered first edge and a square-shaped second edge, wherein the tapered balloon includes a tapered leading edge and a tapered trailing edge, wherein the stepped balloon includes portions of varying diameter, wherein the offset balloon includes a height on a first side of the elongated body member greater than a height on an opposite second side of the elongated body member.
Example 89: The introducer sheath system according to any example herein, particularly examples 56-88, wherein the balloon is made of polymeric material.
Example 90: The introducer sheath system according to any example herein, particularly examples 56-89, wherein the balloon is composed of at least one of a compliant material, a semi-compliant material, and a non-compliant material.
Example 91: The introducer sheath system according to any example herein, particularly example 90, wherein the balloon is composed of a compliant material.
Example 92: The introducer sheath system according to any example herein, particularly example 91, wherein the balloon is composed of at least one of polyolefin, silicone, polyethylene terephthalate.
Example 93: The introducer sheath system according to any example herein, particularly example 90, wherein different portions of the balloon are composed of different ones of the compliant material, semi-compliant material, and non-compliant material.
Example 94: The introducer sheath system according to any example herein, particularly example 93, wherein a proximal portion of the balloon is composed of a less compliant material than a distal portion of the balloon, wherein the proximal portion of the balloon is adjacent the proximal end of the elongated body member and the distal portion of the balloon is adjacent the distal end of the elongated body member.
Example 95: The introducer sheath system according to any example herein, particularly example 94, wherein at least a portion of the proximal portion of the balloon includes a tapered surface.
Example 96: The introducer sheath system according to any example herein, particularly example 95, wherein the tapered surface sized and configured to be located adjacent a distal opening of an introducer sheath such that the tapered surface of the balloon is adapted dilate the distal end of an introducer sheath.
Example 97: The introducer sheath system according to any example herein, particularly examples 56-96, wherein the balloon is composed of an impermeable material.
Example 98: The introducer sheath system according to any example herein, particularly examples 56-97, wherein the balloon is composed of a permeable material.
Example 99: The introducer sheath system according to any example herein, particularly example 98, wherein the balloon comprises a mesh material that allows for fluid communication between an interior of the balloon and an exterior of the balloon.
Example 100: The introducer sheath system according to any example herein, particularly example 99, where if the flow rate of inflation fluid through the mesh material of the balloon is such that the balloon inflates to have a diameter greater than the outer diameter of the elongated body member.
Example 101: The introducer sheath system according to any example herein, particularly examples 56-100, including an inflation fluid comprises saline.
Example 102: The introducer sheath system according to any example herein, particularly example 101, wherein the inflation fluid includes a contrast medium.
Example 103: The introducer sheath system according to any example herein, particularly examples 56-102, wherein the balloon has a uniform thickness along a length and/or around a circumference of the balloon.
Example 104: The introducer sheath system according to any example herein, particularly examples 56-103, wherein a thickness of the balloon varies along a length and/or around a circumference of the balloon.
Example 105: The introducer sheath system according to any example herein, particularly example 104, wherein a thickness of a proximal portion of the balloon is greater than a thickness of a distal portion of the balloon, wherein the proximal portion of the balloon is adjacent the proximal end of the elongated body member and the distal portion of the balloon is adjacent the distal end of the elongated body member.
Example 106: The introducer sheath system according to any example herein, particularly example 104, wherein a thickness of a distal portion of the balloon is greater than a thickness of a proximal portion of the balloon, wherein the proximal portion of the balloon is adjacent the proximal end of the elongated body member and the distal portion of the balloon is adjacent the distal end of the elongated body member.
Example 107: The introducer sheath system according to any example herein, particularly example 104, wherein the balloon includes at least one circumferential band of increased thickness.
Example 108: The introducer sheath system according to any example herein, particularly examples 56-107, wherein the balloon is coupled to the elongated body member such that there is no break between an outer surface of the elongated body member and an outer surface of the balloon.
Example 109: The introducer sheath system according to any example herein, particularly examples 56-108, wherein, in the inflated configuration, the diameter of the balloon is up to about 75% larger than the diameter of the elongated body member.
Example 110: The introducer sheath system according to any example herein, particularly example 61, wherein the maximum diameter of the balloon in the inflated configuration is about 50% larger than the diameter of the elongated body member.
Example 111: A method of pre-dilating an introducer sheath tip comprising: positioning an expandable introducer within a central lumen of an expandable sheath, the introducer including: an elongated body member; an inflatable balloon disposed between a proximal and distal end of the elongated body member, the balloon expandable from a deflated configuration to an inflated configuration, when in the deflated configuration an initial diameter of the balloon corresponds to an outer diameter of the elongated body member, when in the inflated configuration, the inflated dimeter of the balloon is greater than the outer diameter of the elongated body member; and an inflation lumen in fluid communication with the inflatable balloon, the inflation sized and configured for providing an inflation fluid to the balloon; advancing the introducer axially within the central lumen of the sheath such that the inflatable balloon is axially aligned with a distal opening of the sheath; inflating the balloon to the inflated diameter, where the inflated diameter of the balloon is greater than an initial diameter of the distal opening and thereby expanding a diameter of the distal opening of the sheath; deflating the balloon; and withdrawing the introducer from the central lumen of the sheath.
Example 112: The method according to any example herein, particularly example 111, wherein positioning the introducer within the central lumen of the sheath includes fitting at least a portion of an outer surface of the introducer against a surface of the central lumen of the sheath proximate the distal opening.
Example 113: The method according to any example herein, particularly example 112, wherein the introducer is fitted against the surface of the central lumen by at least one of a press fit and an interference fit.
Example 114: The method according to any example herein, particularly examples 111-113, wherein positioning the introducer within the central lumen of the sheath includes positioning the introducer such that the distal end of the elongated body member of the introducer extends through and beyond the distal opening of the central lumen.
Example 115: The method according to any example herein, particularly examples 111-114, wherein advancing the introducer axially within the central lumen of the sheath includes advancing the distal end of the elongated body member beyond the distal opening of the central lumen, wherein axial movement of the elongated body member through the distal opening is limited such that when the elongated body member is provided in a distal-most position the balloon is aligned axially with the distal opening of the introducer sheath.
Example 116: The method according to any example herein, particularly examples 111-115, wherein advancing the introducer axially includes positioning the balloon such that a first portion of the balloon extends beyond the distal opening of the sheath and a second portion of the balloon is positioned within the central lumen of the sheath.
Example 117: The method according to any example herein, particularly example 116, wherein the second portion of the balloon includes a tapered surface adapted to expand the at least a portion of the distal end of the sheath to a corresponding tapered shape.
Example 118: The method according to any example herein, particularly examples 111-117, wherein the diameter of the distal opening of the introducer sheath when expanded is up to about 75% larger than a diameter of the distal opening of the introducer sheath when not expanded.
Example 119: A method of delivering a medical device comprising: inserting an expandable sheath and an expandable introducer at least partially into the vasculature of the patient, the introducer received within a central lumen of the sheath; advancing the introducer axially within the central lumen of the sheath such that an inflatable balloon disposed on an elongated body member of the introducer is axially aligned with a distal opening of the sheath; inflating the balloon to a diameter greater than an initial diameter of the distal opening and thereby expanding a diameter of the distal opening of the sheath; deflating the balloon; withdrawing the introducer from the central lumen of the sheath; advancing a medical device through the central lumen of the sheath; and delivering the medical device to the patient.
Example 120: The method according to any example herein, particularly example 119, wherein during insertion, at least a portion of an outer surface of the introducer is fitted against a surface of the central lumen of the sheath proximate the distal opening.
Example 121: The method according to any example herein, particularly example 120, wherein the introducer is fitted against the surface of the central lumen by at least one of a press fit and an interference fit.
Example 122: The method according to any example herein, particularly examples 119-121, wherein the introducer is received within the central lumen of the sheath such that a distal end of the introducer extends through and beyond the distal opening of the central lumen.
Example 123: The method according to any example herein, particularly examples 119-122, wherein advancing the introducer axially within the central lumen of the sheath includes advancing the distal end of the elongated body member beyond the distal opening of the central lumen, wherein axial movement of the elongated body member through the distal opening is limited such that when the elongated body member is provided in a distal-most position the balloon is aligned axially with the distal opening of the introducer sheath.
Example 124: The method according to any example herein, particularly examples 119-123, wherein advancing the introducer axially includes positioning the balloon such that a first portion of the balloon extends beyond the distal opening of the expandable sheath and a second portion of the balloon is positioned within the central lumen of the sheath.
Example 125: The method according to any example herein, particularly examples 119-124, wherein the diameter of the distal opening of the introducer sheath when expanded is up to about 75% larger than a diameter of the distal opening of the introducer sheath when not expanded.
Example 126: The method according to any example herein, particularly examples 119-125, further comprising: inserting a guidewire at least partially into the vasculature of the patient; advancing the introducer over the guidewire to a treatment position within the patient's vasculature.
Example 127: The method according to any example herein, particularly example 126, further comprising withdrawing the guidewire from the introducer.
Example 128: The method according to any example herein, particularly examples 119-127, further comprising: visualizing the position of at least one of the expandable sheath and the introducer within the vasculature using an imaging modality, wherein the introducer includes a radio opaque marker located proximate at least one of the tapered distal end, a leading end of the balloon, and a trailing end of the balloon.
Example 129: The method according to any example herein, particularly examples 119-128, wherein inflating the balloon includes providing an inflation fluid to the balloon via an inflation lumen extending though the introducer in fluid communication in an interior volume of the balloon.
Example 130: The method according to any example herein, particularly examples 119-129, wherein the balloon includes a tapered surface adapted to expand the at least a portion of the distal end of the sheath to a corresponding tapered shape.
Example 131: The method according to any example herein, particularly examples 119-130, wherein withdrawing the withdrawing the introducer from the central lumen of the sheath includes moving the introducer axially towards a proximal end of the sheath until the introducer is completely removed from the central lumen.
Example 132: The method according to any example herein, particularly examples 119-131, wherein the diameter of the distal opening of the sheath remains expanded after the balloon is deflated and the introducer withdrawn.
Example 133: The method according to any example herein, particularly examples 119-132, wherein advancing a medical device through the central lumen of the sheath further comprises: advancing the medical device through the central lumen of the sheath as the medical device applies an outward radial force on an inner surface of the central lumen; locally expanding the sheath from an initial non-expanded state to a locally expanded state; at least partially unfolding a plurality of longitudinally-extending folds in the sheath during local expansion of the sheath; and locally collapsing the sheath from the locally expanded state at least partially back to the collapsed state after passage of the medical device.
Example 134: The method according to any example herein, particularly examples 119-133, wherein advancing a medical device through the central lumen of the sheath further comprises advancing the medical device at a push force less than the push force required for a sheath with a non-expanded tip.
Example 135: The method according to any example herein, particularly examples 119-134, wherein delivering the medical device to the patient further comprises advancing the medical device through the distal opening of the sheath for placement at a treatment site.
Example 136: The method according to any example herein, particularly examples 119-135, wherein the medical device is a prosthetic heart valve.
Example 137: The method according to any example herein, particularly example 136, wherein the prosthetic heart valve comprises a self-expanding heart valve.
Example 138: The method according to any example herein, particularly example 136, wherein the prosthetic heart valve comprises a balloon-expanding heart valve.
Example 139: The method according to any example herein, particularly examples 119-138, further comprising: removing the sheath from the patient after the medical device is delivered to the patient.
Example 140: An expansion device that is configured to be received within an expandable sheath, the device comprising: a body comprising an outer surface, a proximal end, and a tapered distal end opposite and spaced apart from the proximal end of the body; a radially extending protrusion disposed along a portion of the body, the radially extending protrusion having an outer surface, the radially extending protrusion has a diameter greater than a diameter of the body, and wherein the device is sized and configured to be received within a central lumen of an expandable sheath such that the radially extending protrusion at least partially expands a portion of the expandable sheath.
Example 141: The expansion device according to any example herein, particularly example 140, wherein the outer surface of the body and the outer surface of the radially extending protrusion include a hydrophilic coating.
Example 142: The expansion device according to any example herein, particularly example 141, wherein the hydrophilic coating comprises a material with a low coefficient of friction.
Example 143: The expansion device according to any example herein, particularly examples 140-142, wherein the radially extending protrusion is fixedly disposed at a location along the length of the body.
Example 144: The expansion device according to any example herein, particularly example 143, wherein the radially extending protrusion is molded to the outer surface of the body.
Example 145: The expansion device according to any example herein, particularly example 143, wherein the radially extending protrusion is fixedly disposed to the body through an adhesive, fasteners, or welding.
Example 146: The expansion device according to any example herein, particularly examples 140-142, wherein the radially extending protrusion is adjustably disposed at a location along the length of the body.
Example 147: The expansion device according to any example herein, particularly example 146, wherein the outer surface of the body comprises a first plurality of threads that extend along a portion of the length of the body, wherein the radially extending protrusion comprises an inner surface including a second plurality of threads that correspond to the first plurality of threads such that the radially extending protrusion is configured to be rotationally adjustable around the body, wherein the radially extending protrusion is axially movable along the body by engagement between first and second plurality of threads.
Example 148: The expansion device according to any example herein, particularly examples 140-147, wherein the diameter of the body is 2F, and the diameter of the radially extending protrusion is greater than 2F.
Example 149: The expansion device according to any example herein, particularly examples 140-147, wherein the diameter of the body is 4F, and the diameter of the radially extending protrusion is greater than 4F.
Example 150: The expansion device according to any example herein, particularly examples 140-147, wherein the diameter of the body is 6F, and the diameter of the radially extending protrusion is greater than 6F.
Example 151: The expansion device according to any example herein, particularly examples 140-147, wherein the diameter of the body is 8F, and the diameter of the radially extending protrusion is greater than 8F.
Example 152: The expansion device according to any example herein, particularly examples 140-147, wherein the diameter of the body is 10F, and the diameter of the radially extending protrusion is greater than 10F.
Example 153: The expansion device according to any example herein, particularly examples 140-147, wherein the diameter of the body is 12F, and the diameter of the radially extending protrusion is greater than 12F.
Example 154: The expansion device according to any example herein, particularly examples 140-147, wherein the diameter of the body is 14F, and the diameter of the radially extending protrusion is greater than 14F.
Example 155: The expansion device according to any example herein, particularly examples 140-147, wherein the diameter of the body is 16F, and the diameter of the radially extending protrusion is greater than 16F.
Example 156: The expansion device according to any example herein, particularly examples 140-147, wherein the diameter of the body is 20F, and the diameter of the radially extending protrusion is greater than 20F.
Example 157: The expansion device according to any example herein, particularly examples 140-147, wherein the diameter of the body is 24F, and the diameter of the radially extending protrusion is greater than 24F.
Example 158: The expansion device according to any example herein, particularly examples 140-147, wherein the diameter of the body is 28F, and the diameter of the radially extending protrusion is greater than 28F.
Example 159: The expansion device according to any example herein, particularly examples 140-158, wherein the radially extending protrusion is disposed between the proximal end and the tapered distal end of the body.
Example 160: The expansion device according to any example herein, particularly example 159, wherein the radially extending protrusion is disposed adjacent the tapered distal end of the body.
Example 161: The expansion device according to any example herein, particularly example 160, wherein the radially extending protrusion is offset from a proximal end of the tapered distal tip.
Example 162: The expansion device according to any example herein, particularly examples 140-159, wherein the radially extending protrusion is disposed adjacent the proximal end of the body.
Example 163: The expansion device according to any example herein, particularly example 162, wherein the radially extending protrusion is offset from the proximal end of the body.
Example 164: The expansion device according to any example herein, particularly examples 140-163, wherein the radially extending protrusion is spherically shaped.
Example 165: The expansion device according to any example herein, particularly examples 140-163, wherein the radially extending protrusion is cylindrically shaped.
Example 166: The expansion device according to any example herein, particularly examples 140-165, wherein radially extending protrusion has a curved leading end and curved trailing end.
Example 167: The expansion device according to any example herein, particularly examples 140-166, wherein the radially extending protrusion has a tapered leading end.
Example 168: The expansion device according to any example herein, particularly examples 140-167, wherein the radially extending protrusion has a tapered trailing end.
Example 169: The expansion device according to any example herein, particularly examples 140-168, wherein the device is a dilator.
Example 170: The expansion device according to any example herein, particularly examples 140-168, wherein the device is an introducer.
Example 171: The expansion device according to any example herein, particularly example 170, further comprising a locking mechanism disposed along the proximal end of the body.
Example 172: The expansion device according to any example herein, particularly example 171, wherein a diameter of the locking mechanism is larger than the diameter of the body.
Example 173: The expansion device according to any example herein, particularly example 171 or 172, wherein the locking mechanism is adjustably disposable along at least a portion of the length of the body
Example 174: A sheath system comprising: an expandable sheath comprising: an inner layer defining a central lumen of the sheath; an outer layer extending at least partially around the inner layer, wherein the inner layer and outer layer transition from a non-expanded and an expanded configuration; an expansion device movable within the central lumen of the sheath, the device comprising: a body including an outer surface, a proximal end and a tapered distal end opposite and spaced apart from the proximal end; a radially extending protrusion disposed along a portion of the body, the radially extending protrusion having an outer surface having a diameter greater than a diameter of the body, wherein receipt of the expansion device within the central lumen of the sheath causes the sheath to locally expand at least a portion of the sheath in response to the outwardly directed radial force provided by the radially extending protrusion.
Example 175: The sheath system according to any example herein, particularly example 174, wherein removal of expansion device from the central lumen of the outer layer causes the outer layer to locally contract from the expanded configuration at least partially back to the non-expanded configuration.
Example 176: The sheath system according to any example herein, particularly examples 174 or 175, wherein the inner layer includes a folded portion configured to move between a folded configuration and a less folded configuration during local expansion of the sheath.
Example 177: The sheath system according to any example herein, particularly example 176, wherein the folded portion comprises a first folded region and a second folded region and an overlapping portion extending between the first and second regions, wherein the first folded region is configured to move closer to the second folded region to shorten the overlapping portion at a local axial location during application of a radial outward force by passage of the expansion device and wherein shortening of the overlapping portion corresponds with a local expansion of the lumen.
Example 178: The sheath system according to any example herein, particularly example 177, wherein the first folded region is configured to move further away from the second folded region to lengthen the overlapping portion at the local axial location after removal of the radial outward force and wherein lengthening of the overlapping portion corresponds with a local contraction of the lumen.
Example 179: The sheath system according to any example herein, particularly examples 177 or 178, wherein the first folded region and the second folded region are circumferentially spaced from each other, wherein the overlapping portion extends circumferentially between the first and second folded regions.
Example 180: The sheath system according to any example herein, particularly examples 177-179, wherein the inner layer defines a circumferentially continuous layer and the overlapping portion is radially spaced from an outer surface of a non-overlapping portion of the inner layer; wherein the outer layer defines a discontinuous outer layer including an underlying portion radially spacing the overlapping portion away from the outer surface of the non-overlapping portion.
Example 181: The sheath system according to any example herein, particularly examples 174-180, wherein the expandable sheath further includes: an elastic outer cover extending around the outer layer exerting a radially inward force on the inner and outer layers.
Example 182: The sheath system according to any example herein, particularly examples 174-181, wherein the outer surface of the body and the radially extending protrusion of the expansion device include a hydrophilic coating.
Example 183: The sheath system according to any example herein, particularly examples 174-182, wherein the radially extending protrusion is fixedly disposed at a location along the length of the body.
Example 184: The sheath system according to any example herein, particularly examples 174-182, wherein the radially extending protrusion is adjustably disposed at a location along the length of the body.
Example 185: The sheath system according to any example herein, particularly example 184, wherein the outer surface of the body comprises a first plurality of threads that extend along a portion of the length of the body, wherein the radially extending protrusion comprises an inner surface including a second plurality of threads that correspond to the first plurality of threads such that the radially extending protrusion is configured to be rotationally adjustable around the length of the body, wherein the radially extending protrusion is axially movable along the body by engagement between first and second plurality of threads.
Example 186: The sheath system according to any example herein, particularly examples 174-185, wherein the expandable sheath includes a strain relief portion adjacent a proximal end of the sheath and an elongated body portion extending between the strain relief portion and a distal end of the sheath, the strain relief portion having a larger diameter than the elongated body portion of the sheath, wherein the diameter of the radially extending protrusion is greater than the diameter of the strain relief portion.
Example 187: The sheath system according to any example herein, particularly example 186, wherein a distal end of the strain relief portion includes a decreasing taper between the diameter of the strain relief portion and the diameter of the elongated body portion.
Example 188: The sheath system according to any example herein, particularly examples 174-187, wherein the expansion device further includes a locking mechanism for engaging the sheath and fixing the axial position of the expansion device within the central lumen of the sheath.
Example 189: The sheath system according to any example herein, particularly example 188, wherein the expandable sheath is coupled to a sheath hub at the proximal end, wherein the locking mechanism engages the sheath hub to fix the axial position of the expansion device within the central lumen of the sheath.
Example 190: A method of locally expanding an expandable sheath comprising: introducing an expansion device within a central lumen of the expandable sheath; introducing the combined expandable sheath and expansion device into a patient's vascular; advancing the expansion device distally within the central lumen of the expandable sheath to locally expand the lumen of the sheath at a local axial location corresponding to an axial location of a radially extending protrusion provided on the expansion device.
Example 191: The method according to any example herein, particularly example 190, wherein introducing an expansion device within the central lumen of the expandable sheath includes: positioning the expansion device within the central lumen of the sheath such that the radially extending protrusion is at least disposed within a strain relief portion of the expandable sheath.
Example 192: The method according to any example herein, particularly example 191, wherein locally expanding the lumen of the sheath further comprises: advancing the expansion device beyond the strain relief portion of the sheath and into an elongated body portion of the sheath.
Example 193: The method according to any example herein, particularly examples 190-192, further comprising removing the expansion device from the expandable sheath such that the outer diameter of the sheath is greater than the non-expanded, initial, diameter of the sheath.
Example 194: The method according to any example herein, particularly example 193, further comprising inserting a medical device into the central lumen of the expandable sheath.
Example 195: A method of locally expanding an expandable sheath comprising: introducing an expandable sheath into a patient's vascular, the expandable sheath having a central lumen; introducing the expansion device into the central lumen of the expandable sheath; advancing the expansion device distally within the central lumen of the expandable sheath to locally expand the lumen of the sheath at a local axial location corresponding to an axial location of a radially extending protrusion provided on the expansion device.
Example 196: The method according to any example herein, particularly example 195, wherein introducing an expansion device within the central lumen of the expandable sheath includes: positioning the expansion device within the central lumen of the sheath such that the radially extending protrusion is at least disposed within a strain relief portion of the expandable sheath.
Example 197: The method according to any example herein, particularly example 196, wherein locally expanding the lumen of the sheath further comprises: advancing the expansion device beyond the strain relief portion of the sheath and into an elongated body portion of the sheath.
Example 198: The method according to any example herein, particularly examples 195-197, further comprising removing the expansion device from the expandable sheath such that the outer diameter of the sheath is greater than the non-expanded, initial, diameter of the sheath.
Example 199: The method according to any example herein, particularly example 198, further comprising inserting a medical device into the central lumen of the expandable sheath.
In view of the many possible aspects to which the principles of the disclosed disclosure can be applied, it should be recognized that the illustrated aspects are only preferred examples of the disclosure and should not be taken as limiting the scope of the disclosure. Rather, the scope of the disclosure is defined by the following claims. We, therefore, claim as our disclosure all that comes within the scope and spirit of these claims.
This application is a continuation of a PCT Application No. PCT/US2021/041991, filed Jul. 16, 2021, entitled EXPANDABLE INTRODUCER FOR DILATING THE DISTAL TIP OF AN INTRODUCER SHEATH, which claims the benefit of U.S. Provisional Patent Application No. 63/053,506, filed Jul. 17, 2020, entitled EXPANDABLE INTRODUCER FOR DILATING THE DISTAL TIP OF AN INTRODUCER SHEATH, where each of above-referenced application is incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 63053506 | Jul 2020 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/US2021/041991 | Jul 2021 | US |
| Child | 18097365 | US |
