Patent Application
20230009249
The present disclosure concerns embodiments of assemblies, and related methods, for providing a more continuous transition, via a transition element, between a prosthetic medical device and a nosecone of a delivery apparatus adapted to deliver the prosthetic medical device to a target implantation site.
The human heart can suffer from various valvular diseases. These valvular diseases can result in significant malfunctioning of the heart and ultimately require repair of the native valve or replacement of the native valve with an artificial valve. There are a number of known repair devices (e.g., stents) and artificial valves, as well as a number of known methods of implanting these devices and valves in humans. Percutaneous and minimally-invasive surgical approaches are used in various procedures to deliver prosthetic medical devices to locations inside the body that are not readily accessible by surgery or where access without surgery is desirable. In one specific example, a prosthetic heart valve can be mounted in a crimped state on the distal end of a delivery device (e.g., delivery apparatus), proximate to a nosecone of the delivery device, and advanced through the patient's vasculature (e.g., through a femoral artery and the aorta) until the prosthetic valve reaches the implantation site in the heart. The prosthetic valve is then expanded to its functional size, for example, by inflating a balloon on which the prosthetic valve is mounted, actuating a mechanical actuator that applies an expansion force to the prosthetic valve, or by deploying the prosthetic valve from a sheath of the delivery device so that the prosthetic valve can self-expand to its functional size.
Prosthetic valves that rely on a mechanical actuator for expansion can be referred to as “mechanically expandable” prosthetic heart valves. The actuator typically takes the form of pull cables, sutures, wires and/or shafts that are configured to transmit expansion forces from a handle of the delivery apparatus to the prosthetic valve.
In some embodiments, after the prosthetic valve is deployed from the sheath of the delivery device, but prior to being actively expanded via actuators of the delivery device, the prosthetic valve may assume a partially expanded (e.g., non-compressed) diameter that is larger than its fully compressed diameter (after being crimped) and smaller than its fully expanded diameter (after being expanded via actuators of the delivery device). As a result of this expansion in diameter, a gap may form between the nosecone of the delivery device and a distal end of the prosthetic valve. This gap creates a discontinuity between the prosthetic valve and the nosecone which may make it difficult to reposition the valve at the target implantation site. For example, in some embodiments, the gap may cause the prosthetic valve to come into unwanted contact with the patient's anatomy during repositioning of the valve. Accordingly, improvements in delivery devices which reduce gap formation between a nosecone of the delivery device and the prosthetic valve (after deployment from a sheath of the delivery device, in some examples), are desirable.
Disclosed herein are assemblies including a prosthetic valve and delivery apparatus and related methods for delivering a prosthetic valve to and implanting the prosthetic valve at a target implantation site with a delivery apparatus. The delivery apparatuses (which can also be referred to herein as delivery devices) can be used to deliver an implantable medical device, such as a prosthetic heart valve, to a target site in a patient, such as a heart. In some embodiments, delivery apparatuses can be a component of a delivery system (e.g., an endovascular or transcatheter delivery system) that can be used to deliver a prosthetic heart valve or other implantable medical device.
In some embodiments, the delivery apparatus may be configured with an expandable transition element that is arranged, in a non-expanded (e.g., compressed) state, within an outer shaft of the delivery apparatus during delivery (e.g., maneuvering) of the delivery apparatus to the target implantation site. The transition element may be adapted to expand from the non-expanded state within the outer shaft to an expanded state outside the outer shaft, where, in the expanded state, the transition element forms a continuous transition from a nosecone of the delivery apparatus to the prosthetic valve when a distal end of the outer shaft is moved away from the nosecone to uncover the prosthetic valve. The expandable transition element may be one of an inflatable balloon, a pre-inflated balloon, a compressible element (such as a sponge), and a mechanical element (having an expandable frame).
In one representative embodiment, an assembly includes a prosthetic valve and a delivery apparatus. The delivery apparatus includes an outer shaft with a distal end portion forming a sheath adapted to enclose the prosthetic valve therein in a radially compressed configuration; an inner shaft arranged within the outer shaft and including a nosecone arranged at a distal end of the inner shaft, the nosecone arranged outside of the outer shaft, at the distal end portion of the outer shaft; and an expandable transition element adapted to expand from a non-expanded state within the outer shaft to an expanded state outside the outer shaft, wherein, in the expanded state, the transition element forms a continuous transition from the nosecone to the prosthetic valve when the sheath is moved away from the nosecone to uncover the prosthetic valve.
In some embodiments, the delivery apparatus further comprises at least one actuator assembly arranged within the outer shaft and releasably coupled to the prosthetic valve.
In some embodiments, the transition element is a balloon.
In some embodiments, the balloon is an inflatable balloon that is inflatable from a deflated state prior to removal of the prosthetic valve from the sheath to an inflated state after removal of the prosthetic valve from the sheath. Further, in some embodiments, when the balloon is in the deflated state, it is arranged within an interior of the sheath, between the nosecone and a distal end of the prosthetic valve, in the radially compressed configuration. In some embodiments, when the balloon is in the inflated state, it is arranged exterior to the outer shaft and between the nosecone and a distal end of the prosthetic valve.
In some embodiments, the balloon is a compliant balloon formed from an elastic material and is configured to be inflated to a desired size within a range of possible sizes based on a size of the prosthetic valve.
In some embodiments, the balloon is a semi-compliant balloon comprising Pebax.
In some embodiments, the balloon is a noncompliant balloon formed from a non-elastic material and is configured to expand to a predetermined size when fully inflated, where the predetermined size is selected based on a size of the prosthetic valve.
In some embodiments, the balloon is a pre-inflated balloon, pre-inflated to an expanded state, that passively transitions between a compressed state when positioned within the sheath to the expanded state when the sheath is moved away from the balloon.
In some embodiments, the transition element is a compressible element including one or more of a compressible foam and a sponge. In some embodiments, a proximal end of the compressible element is tapered inward toward a central longitudinal axis of the assembly.
In some embodiments, the transition element is an expandable, mechanical element. In some embodiments, the mechanical element comprises an expandable frame including a plurality of arms, wherein each arm of the plurality of arms includes a distal end attached to the nosecone and a proximal end that is unattached to the delivery apparatus and adapted to expand from a compressed state to an expanded state. In some embodiments, the mechanical element further comprises a cover surrounding the plurality of arms, around a circumference of the expandable frame. In some embodiments, the mechanical element further comprises a compression mechanism configured to re-compress the frame from the expanded state to the compressed state.
In some embodiments, in the expanded state, a proximal end of the transition element contacts a distal end of the prosthetic valve and a distal end of the transition element contacts a proximal end of the nosecone.
In some embodiments, a distal end of the transition element is attached to a proximal end of the nosecone.
In another representative embodiment, a method includes advancing a delivery apparatus of a transcatheter delivery system to a target implantation site in a patient, the delivery apparatus including an outer shaft with a distal end portion forming a sheath enclosing a radially compressed prosthetic valve therein, proximate to a proximal end of a nosecone of the delivery apparatus; after reaching the target implantation site, moving the distal end portion of the outer shaft away from the nosecone, in an axial direction, to uncover the prosthetic valve; and expanding a transition element of the delivery apparatus in a space formed between the proximal end of the nosecone and a distal end of the prosthetic valve.
In some embodiments, the prosthetic valve expands to a partially expanded state upon moving the distal end portion of the outer shaft away from the nosecone.
In some embodiments, the method can further include, after expanding the transition element, repositioning the prosthetic valve, in the partially expanded state, at the target implantation site.
In some embodiments, the method can further include, after repositioning the prosthetic valve, actively expanding, in a radial direction, the prosthetic valve to a radially expanded state.
In some embodiments, actively expanding the prosthetic valve includes actively expanding the prosthetic valve via one or more actuator assemblies of the delivery apparatus, the one or more actuator assembly extending from an interior of the outer shaft and coupled to the prosthetic valve.
In some embodiments, the transition element is an inflatable balloon and expanding the transition element includes inflating the inflatable balloon from a deflated state to an inflated state.
In some embodiments, the inflatable balloon is a compliant balloon formed from an elastic material and inflating the inflatable balloon from the deflated state to the inflated state includes inflating the inflatable balloon to a desired size within a range of possible sizes that is based on a size of the prosthetic valve.
In some embodiments, the inflatable balloon is a semi-compliant balloon comprising Pebax and inflating the inflatable balloon from the deflated state to the inflated state includes inflating the inflatable balloon to a desired size within a range of possible sizes that is based on a size of the prosthetic valve.
In some embodiments, the inflatable balloon is a noncompliant balloon formed from a non-elastic material and inflating the inflatable balloon from the deflated state to the inflated state includes inflating the inflatable balloon to a predetermined size that is selected based on a size of the prosthetic valve.
In some embodiments, a distal end of the inflatable balloon is attached to the proximal end of the nosecone.
In some embodiments, the transition element is a pre-inflated balloon and expanding the transition element includes passively expanding the pre-inflated balloon from a radially compressed state to a radially expanded state, wherein the pre-inflated balloon assumes its pre-inflated size when in the radially expanded state.
In some embodiments, the transition element is a compressible element including one of a compressible foam and a sponge material and expanding the transition element includes passively expanding the compressible element from a compressed state to an expanded, non-compressed state, wherein the compressible element is in its resting state when in the expanded state.
In some embodiments, the transition element is a mechanical element comprising an expandable frame having a distal end coupled to the nosecone and expanding the transition element includes expanding a proximal end of the expandable frame from a compressed state to an expanded state.
In another representative embodiment, an assembly can include a mechanically expandable prosthetic valve including a distal end and a proximal end and a delivery apparatus. The delivery apparatus can include an outer shaft with a distal end portion forming a sheath adapted to enclose the prosthetic valve therein in a radially compressed configuration; at least one actuator assembly arranged within the outer shaft and releasably coupled to the prosthetic valve; an inner shaft arranged within the outer shaft and including a nosecone arranged at a distal end of the inner shaft, the nosecone arranged outside of the outer shaft and proximate to the distal end of the prosthetic valve; and an expandable transition element adapted to expand from a non-expanded state within the outer shaft to an expanded state outside the outer shaft, wherein, in the expanded state, the transition element forms a continuous transition from a proximal end of the nosecone to the distal end of the prosthetic valve when the sheath is moved away from the nosecone to uncover the prosthetic valve.
In some embodiments, a distal end of the transition element is attached to the proximal end of the nosecone.
In some embodiments, the transition element is an inflatable balloon adapted to be inflated from a deflated state prior to removal of the prosthetic valve from the sheath to an inflated state after removal of the prosthetic valve from the sheath.
In some embodiments, the balloon is a compliant balloon formed from an elastic material and is configured to be inflated to a desired size within a range of possible sizes based on a size of the prosthetic valve.
In some embodiments, the balloon is a semi-compliant balloon comprising Pebax.
In some embodiments, the balloon is a noncompliant balloon formed from a non-elastic material and is configured to expand to a predetermined size when fully inflated, wherein the predetermined size is selected based on a size of the prosthetic valve.
In some embodiments, the transition element is a pre-inflated balloon, pre-inflated to an expanded state, that passively transitions between a compressed state when positioned within the sheath to the expanded state when the sheath is moved away from the balloon.
In some embodiments, the pre-inflated balloon is pre-filled with saline.
In some embodiments, the pre-inflated balloon is pre-filled with a hydrogel.
In some embodiments, the transition element is a compressible element including one or more of a compressible foam and a sponge.
In some embodiments, the transition element is an expandable, mechanical element comprising an expandable frame including a plurality of arms, wherein each arm of the plurality of arms includes a distal end attached to the nosecone and a proximal end that is unattached to the delivery apparatus and adapted to expand from a compressed state when positioned within the sheath to an expanded state when the sheath is moved away from the mechanical element.
In some embodiments, when in the expanded state, the transition element tapers in diameter from the distal end of the prosthetic valve to the proximal end of the nosecone.
In another representative embodiment, an assembly includes a prosthetic valve and a delivery apparatus. The delivery apparatus includes an outer shaft with a distal end portion forming a sheath adapted to enclose the prosthetic valve therein in a radially compressed configuration; an inner shaft arranged within the outer shaft and including a nosecone arranged at a distal end of the inner shaft, the nosecone arranged outside of the outer shaft, wherein the outer shaft and the inner shaft are configured to move axially relative to one another to move the nosecone away from the distal end portion of the outer shaft and uncover the prosthetic valve; and an expandable transition element disposed between the prosthetic valve and the nosecone, the expandable transition element adapted to expand from a non-expanded state within the outer shaft to an expanded state outside the outer shaft, wherein the transition element is in the non-expanded state when the sheath covers the prosthetic valve and the transition element and is in the expanded state when the sheath is moved away from the nosecone to uncover the prosthetic valve and wherein, in the expanded state, the transition element forms a continuous transition from the nosecone to the prosthetic valve.
In some embodiments, a distal end of the transition element is attached to a proximal end of the nosecone.
In some embodiments, the delivery apparatus further comprises at least one actuator assembly arranged within the outer shaft and releasably coupled to the prosthetic valve.
In some embodiments, the at least one actuator assembly is configured to radially expand the prosthetic heart valve.
In some embodiments, the transition element is a balloon.
In some embodiments, the balloon is an inflatable balloon that is configured to receive an inflation fluid and inflate from a deflated state to an inflated state.
In some embodiments, when the balloon is in the deflated state, it is arranged within an interior of the sheath, between the nosecone and a distal end of the prosthetic valve, in the radially compressed configuration.
In some embodiments, when the balloon is in the inflated state, it is arranged exterior to the outer shaft and between the nosecone and a distal end of the prosthetic valve.
In some embodiments, the balloon is a compliant balloon formed from an elastic material and is configured to be inflated to a desired size within a range of possible sizes based on a size of the prosthetic valve.
In some embodiments, the balloon is a semi-compliant balloon comprising Pebax.
In some embodiments, the balloon is a noncompliant balloon formed from a non-elastic material and is configured to expand to a predetermined size when fully inflated, wherein the predetermined size is selected based on a size of the prosthetic valve.
In some embodiments, the balloon is a pre-inflated balloon, pre-inflated to an expanded state, that passively transitions between a compressed state when positioned within the sheath to the expanded state when the sheath is moved away from the balloon.
In some embodiments, the transition element is a compressible element including one or more of a compressible foam and a sponge.
In some embodiments, a proximal end of the compressible element is tapered inward toward a central longitudinal axis of the assembly.
In some embodiments, the transition element is an expandable, mechanical element.
In some embodiments, the mechanical element comprises an expandable frame including a plurality of arms, where each arm of the plurality of arms includes a distal end attached to the nosecone and a proximal end that is unattached to the delivery apparatus and adapted to expand from a compressed state to an expanded state.
In some embodiments, the mechanical element further comprises a cover surrounding the plurality of arms, around a circumference of the expandable frame.
In some embodiments, the mechanical element further comprises a compression mechanism configured to re-compress the frame from the expanded state to the compressed state.
In some embodiments, in the expanded state, a proximal end of the transition element contacts a distal end of the prosthetic valve and a distal end of the transition element contacts a proximal end of the nosecone.
The foregoing and other objects, features, and advantages of the invention will become more apparent from the following detailed description, which proceeds with reference to the accompanying figures.
Described herein are examples of prosthetic valves, delivery apparatus (or devices) configured to deliver prosthetic valves to target implantation locations within a body, and methods for delivering a prosthetic valve to and implanting the prosthetic valve at a target implantation site with a delivery apparatus. The prosthetic valves (e.g., prosthetic heart valves) may include a frame including a proximal end and distal end. As used herein, the “distal end” of the frame may refer to the end of the frame that is positioned proximate and/or adjacent to a distal shoulder/nosecone of a delivery apparatus when arranged within an outer shaft of the delivery apparatus. For example, the distal end may be oriented further downstream than the proximal end of the frame when the delivery apparatus in which the prosthetic valve is arranged is being advanced through a lumen of a patient, toward a target implantation site.
The delivery apparatus may include an outer shaft with a distal end portion forming a sheath (or capsule) adapted to enclose the prosthetic valve therein in a radially compressed configuration during advancement of the delivery apparatus to the target implantation site. The delivery apparatus may further include an inner shaft arranged within the outer shaft and including a nosecone arranged at a distal end of the inner shaft, the nosecone arranged outside of the outer shaft, at the distal end portion of the outer shaft (while the outer shaft is covering the prosthetic valve). In some embodiments, the delivery apparatus may further include an expandable transition element adapted to expand from a non-expanded state within the outer shaft to an expanded state outside the outer shaft. In the expanded state, the transition element may form a continuous transition, in an axial direction relative to a central longitudinal axis of the delivery apparatus, from the nosecone to the prosthetic valve when the sheath is moved away from the nosecone to uncover the prosthetic valve. As a result, the prosthetic valve may be more easily repositioned via the delivery apparatus at the target implantation site, without causing unwanted contact between sides of the patient's anatomy and the prosthetic valve (which may cause damage to the anatomy or valve in some cases).
The prosthetic valves disclosed herein can be radially compressible and expandable between a radially compressed configuration and a radially expanded configuration. Thus, the prosthetic valves can be crimped on an implant delivery apparatus (e.g., device) in the radially compressed configuration during delivery, and then expanded to the radially expanded configuration once the prosthetic valve reaches the implantation site.
In the depicted embodiments, the first end 14 is an inflow end and the second end 16 is an outflow end. The outflow end 16 can be coupled to a delivery apparatus for delivering and implanting the prosthetic valve within the native aortic valve is a transfemoral, retrograde delivery approach. Thus, in the delivery configuration of the prosthetic valve, the outflow end 16 is the proximal-most end of the prosthetic valve. In other embodiments, the inflow end 14 can be coupled to the delivery apparatus, depending on the particular native valve being replaced and the delivery technique that is used (e.g., trans-septal, transapical, etc.). For example, the inflow end 14 can be coupled to the delivery apparatus (and therefore is the proximal-most end of the prosthetic valve in the delivery configuration) when delivering the prosthetic valve to the native mitral valve via a trans-septal delivery approach.
The prosthetic valve 10 can also include a valvular structure 18 which is coupled to the frame 12 and configured to regulate the flow of blood through the prosthetic valve 10 from the inflow end to the outflow end. The prosthetic valve 10 can further include a plurality of actuators 20 mounted to and equally spaced around the inner surface of the frame 12. Each of the actuators 20 can be configured to form a releasable connection with one or more respective actuators of a delivery apparatus, as further described below.
The valvular structure 18 can include, for example, a leaflet assembly comprising one or more leaflets 22 (three leaflets 22 in the illustrated embodiment) made of a flexible material. The leaflets 22 of the leaflet assembly can be made from in whole or part, biological material, bio-compatible synthetic materials, or other such materials. Suitable biological material can include, for example, bovine pericardium (or pericardium from other sources). The leaflets 22 can be arranged to form commissures 24, which can be, for example, mounted to respective actuators 20. Further details regarding transcatheter prosthetic heart valves, including the manner in which the valvular structure can be coupled to the frame 12 of the prosthetic valve 10, can be found, for example, in U.S. Pat. Nos. 6,730,118, 7,393,360, 7,510,575, 7,993,394, and 8,652,202, and U.S. Patent Application Publication No. 2018/0325665, all of which are incorporated herein by reference in their entireties.
In some embodiments, the prosthetic valve 10 can include a plurality of commissure support elements configured as commissure clasps or clamps 26. In the illustrated configuration, the prosthetic valve includes a commissure clamp 26 positioned at each commissure 24 and configured to grip adjacent portions of two leaflets 22 at each commissure 24, at a location spaced radially inwardly of the frame 12. Each clamp 26 can be mounted on an actuator 20 as shown. In alternative embodiments, the commissure supports elements (such as clamps 26) can be mounted to the struts 28 of the frame, or alternatively, the commissures 24 can be mounted (e.g., sutured) directly to the struts of the frame. Further details of the commissure clamps 26 and other techniques for mounting the commissures of a valve assembly to a frame can be found in U.S. Patent Application Publication No. 2018/0325665.
Although not shown, the prosthetic valve 10 can also include one or more skirts or sealing members. For example, the prosthetic valve 10 can include an inner skirt mounted on the inner surface of the frame. The inner skirt can function as a sealing member to prevent or decrease perivalvular leakage, to anchor the leaflets 22 to the frame, and/or to protect the leaflets against damage caused by contact with the frame during crimping and during working cycles of the prosthetic valve. The prosthetic valve 10 can also include an outer skirt mounted on the outer surface of the frame 12. The outer skirt can function as a sealing member for the prosthetic valve by sealing against the tissue of the native valve annulus and helping to reduce paravalvular leakage past the prosthetic valve. The inner and outer skirts can be formed from any of various suitable biocompatible materials, including any of various synthetic materials (e.g., PET) or natural tissue (e.g., pericardial tissue). The inner and outer skirts can be mounted to the frame using sutures, an adhesive, welding, and/or other means for attaching the skirts to the frame.
The frame 12 can be made of any of various suitable materials, such as stainless steel, a cobalt chromium alloy, or a nickel titanium alloy (“NiTi”), for example Nitinol. Referring again to
In the illustrated embodiment, the struts 28 are pivotably coupled to one another at one or more pivot joints along the length of each strut. For example, in the illustrated configuration, each of the struts 28 can be formed with apertures (see e.g., apertures 114 in
In some embodiments, the frame 12 can be constructed by forming individual components (e.g., the struts and fasteners of the frame) and then mechanically assembling and connecting the individual components together. In other embodiments, the struts 28 are not coupled to each other with respective hinges but are otherwise pivotable or bendable relative to each other to permit radial expansion and contraction of the frame 12. For example, the frame 12 can be formed (e.g., via laser cutting, electroforming or physical vapor deposition) from a single piece of material (e.g., a metal tube). Further details regarding the construction of the frame and the prosthetic valve are described in U.S. patent application Ser. Nos. 15/831,197; 62/515,437; 62/548,855, all of which are incorporated herein by reference. Additional examples of expandable prosthetic valves that can be used with the delivery apparatuses disclosed herein are described in U.S. Publication No. 2015/0135506 and 2014/0296962, which are incorporated herein by reference.
Referring still to
Each push-pull mechanism 32 can generally comprise an inner member 34, such as an inner tubular member, and an outer member 36 disposed about the inner member 34. The inner members 34 and the outer members 36 can be movable longitudinally relative to each other in a telescoping manner to radially expand and contract the frame 12, as further described in U.S. patent application Ser. Nos. 62/430,810, 15/831,197; 15/978,459, which are incorporated herein by reference. The inner members 34 can be, for example, rods, cables, wires, or tubes. The outer members 36 can be, for example, tubes or sheaths having sufficient rigidity such that they can apply a distally directed force to the frame without bending or buckling.
The inner members 34 can have distal end portions 34a coupled to the inflow end 14 of the frame 12 (e.g., with a coupling element such as a pin member 30). In the illustrated embodiment, each of the inner members 34 are coupled to the frame at respective apices 38 at the inflow end 14 of the frame 12. For example, the distal end portion 34a of each inner member 34 can be pivotably connected to the rivet or pin 30 that connects the two struts at the adjacent apex 38. The outer members 36 can be coupled to apices 38 at the outflow end 16 of the frame 12 at, for example, a mid-portion of the outer member 36, as shown in
The inner member 34 and the outer member 36 can telescope relative to each other between a fully contracted state (corresponding to a fully radially expanded state of the prosthetic valve) and a fully extended state (corresponding to a fully radially compressed state of the prosthetic valve). In the fully extended state, the inner member 34 is fully extended from the outer member 36. In this manner, the push-pull mechanisms 32 allow the prosthetic valve to be fully expanded or partially expanded to different diameters and retain the prosthetic valve in the partially or fully expanded state. It should be understood that the inner members 34 and the outer members 36 can be coupled to other locations on the frame to produce radial compression and expansion of the frame, so long as the inner member and outer member of each actuator are coupled at axial spaced pivot joints of the frame.
In use, a delivery apparatus, such as example delivery apparatus (e.g., device) 300 shown in
Once coupled to the delivery apparatus, the prosthetic valve 10 can then be radially collapsed (see e.g.,
The one or more actuator assemblies 200 can be components of a delivery apparatus (e.g., the delivery apparatus 300 of
The screw 208 has an externally threaded surface that can engage an internally threaded surface of the sleeve 110, which is affixed to the frame 102, such as at the distal end of the frame. When the actuator member 202 is rotated to screw the screw 208 into the sleeve 110, the actuator member 202 becomes connected to the distal end of the frame 102 such that proximal or distal motion of the actuator member 202 causes proximal or distal motion, respectively, of the distal end of the frame 102.
The cover tube 204 annularly surrounds the actuator member 202. The cover tube 204 can be connected to the actuator member 202 such that the actuator member 202 and the cover tube 204 rotate together and move axially together. The actuator member 202 and the cover tube 204 extend through the stopper 112, which can be affixed to a proximal end of the frame. The support tube 206 annularly surrounds the cover tube 154. The stopper 112 has an annular inner surface with an inner diameter larger than the outer diameter of the cover tube 204 and the screw 208 such that the cover tube 204 and the screw 208 can be retracted through the stopper 112 as the frame 102 is expanded and once the actuator is retracted proximally by the user to disconnect it from the frame. The stopper 112 is sized to abut or engage the distal end of the support tube 206 such that the support tube 206 is prevented from moving distally beyond the stopper 112.
In operation, prior to implantation in a patient, the screw 208 is threaded into the sleeve 110, thereby connecting the linear actuator assembly 200 to the frame 102. The frame 102 can then be placed in a radially collapsed state and the prosthetic valve and the distal end portion of the delivery apparatus can be inserted in a patient. Once the prosthetic valve 100 is at a desired implantation site, the frame 102 can be radially expanded as described herein.
To radially expand the frame 102, the support tube 206 is held firmly against the stopper 112. The actuator member 202 is then pulled in a proximal direction through the support tube 206, such as by pulling on the proximal end of the actuator member 202 or actuating a control knob on the handle that produces proximal movement of the actuator member 202. Because the support tube 206 is being held against the stopper 112, which is connected to the proximal end of the frame 102, the proximal end of the frame 102 is prevented from moving relative to the support tube 206 and the handle. As such, movement of the actuator member 202 in a proximal direction results in movement of the distal end of the frame 102 in a proximal direction causing the frame 102 to foreshorten axially and expand radially.
It should be understood that the frame 102 can also be radially expanded by pushing the proximal end of the frame toward the distal end of the frame by pushing the support tube 206 against the stopper 112 while keeping the actuator member 202 stationary relative to the handle, or alternatively, by simultaneously pushing the support tube 206 distally against the stopper 112 and pulling the actuator member 202 proximally.
After the frame 102 is expanded to a desired radially expanded size, one or more locking mechanisms can be actuated to lock the frame 102 in the desired radially expanded size, and the linear actuator assembly 200 can be disconnected from the frame 102. To disconnect the linear actuator assembly 200 from the frame 102, the actuator member 202 can be rotated so as to unscrew the screw 208 from the stopper 112. The actuator member 202 and the cover tube 204 can then be retracted proximally through the stopper 112 and the linear actuator assembly 200 (including the actuator member 202, the screw 208, the cover tube 204, and the support tube 206) can be withdrawn from the patient. The cover tube 204 facilitates passage of the screw 208 through the stopper 112. In some embodiments, the cover tube 204 can be excluded. In embodiments that have more than one linear actuator assembly 200, the above procedure for expanding the frame 102 is performed for each linear actuator assembly 150.
Further details of the actuator assemblies and various exemplary locking mechanisms can be found in U.S. Publication No. 2018/0153689.
The delivery apparatus 300 in the illustrated embodiment generally includes a handle 302, an elongate shaft 304 (which comprises an outer, or outermost, shaft in the illustrated embodiment) extending distally from the handle 302, an inner (e.g., innermost) shaft 310, and at least one actuator assembly (e.g., member or actuator) 306 for expanding and compressing the prosthetic valve extending through the outer shaft 304 and distally outwardly from a distal end portion 312 of the outer shaft 304.
The inner shaft 310 can define an inner lumen that is configured to receive a guidewire therein. For example, during delivery of an implantable medical device (e.g., prosthetic heart valve) to the target implantation site with the delivery apparatus 300, the delivery apparatus 300 can be advanced over the guidewire to the target implantation site.
The delivery apparatus 300 can include three actuator assemblies 306 (only two of the three are shown in
In particular embodiments, each actuator assembly 306 can be releasably coupled to a corresponding actuator of the prosthetic valve (e.g., a push-pull mechanism 32 as shown in
As shown in
In use, the delivery apparatus 300 can be releasably coupled to the prosthetic valve 308 to produce radial expansion and compression of the frame of the prosthetic valve 308. In some embodiments, the actuator assemblies 306 of the delivery apparatus 300 can be configured to transfer pushing and/or pulling forces from the handle 302 of the delivery apparatus 300 to the prosthetic valve 308. For example, in some embodiments, the actuator assemblies 306 may have distal end portions that can be releasably connected to the prosthetic valve 308 via respective release-and-locking units.
In some embodiments, the outer shaft 304 of the delivery apparatus 300 can be configured as a steerable guide catheter having an adjustable curvature for use in steering the delivery apparatus 300 through the patient's vasculature. In particular embodiments, the outer shaft 304 can include a steerable distal section, the curvature of which can be adjusted by the operator to assist in guiding the apparatus through the patient's vasculature.
The outer shaft 304 and the actuator assemblies 306 can be moved relative to one another (axially and/or rotationally) to facilitate delivery and positioning of the prosthetic valve 308 at an implantation site in the patient's body.
In some embodiments, the distal end portion 312 of the outer shaft 304 can form and/or function as a sheath (e.g., capsule) that is sized and shaped to receive and house the prosthetic valve 308 in a radially compressed state for delivery into and through a patient's vasculature. Once the prosthetic valve 308 is advanced to the implantation site or adjacent the implantation site, the prosthetic valve 308 can be advanced from the sheath by advancing the actuator assemblies 306 relative to the outer shaft 304, after which the prosthetic valve 308 can be radially expanded. In alternative embodiments, the outer shaft 304 can be configured to move axially relative to the actuator assemblies 306 and the prosthetic valve.
The advancement of the prosthetic valve 308 from the sheath by axially moving the actuator assemblies 306 relative to the outer shaft 304 or by retracting the outer shaft 304 relative to the actuator assemblies 306 may be actuated by operating a first knob 316 on the handle 302. The first knob 316 can be operatively connected to a proximal end portion of the outer shaft 304 and can be configured to retract the outer shaft 304 proximally relative to the actuator assemblies 306 to deploy the prosthetic valve 308 from the distal end portion 312 of the sheath or operatively connected to proximal ends of the actuator assemblies 306 to advance the actuator assemblies 306 distally relative to the outer shaft 304 to deploy the prosthetic valve 308 from the distal end portion 312 of the sheath. The first knob 316 may be a slidable or rotatable adjustment element that is operatively connected to the actuator assemblies 306 and/or the outer shaft 304.
The handle 302 may include additional adjustment knobs, such as a second knob 318 and a third knob 320, as shown in
In some embodiments, the third knob 320 may be operatively coupled to the actuator assemblies 306 and actuate the actuator assemblies 306 to disconnect from the prosthetic valve 308. As a result, the prosthetic valve 308 may be detached from the delivery apparatus 300 and implanted (e.g., deployed) at the target implantation site.
Turning now to
In some embodiments, as shown in
Though only two actuator assemblies 306 are shown in
As shown in
After reaching the target implantation site, the sheath 322 may be pulled away from the nosecone 314 and the prosthetic valve 308, in a proximal direction along a central longitudinal axis of the delivery apparatus 300, to uncover the prosthetic valve 308. In alternate embodiments, the actuator assemblies 306 may be advanced, in the distal direction, to move the prosthetic valve 308 out of the sheath 322.
In the partially expanded state, as shown in the example of
In some cases, the actuator assemblies 306 can be configured to prevent any expansion of the prosthetic valve 308 after it is advanced from the sheath 322 but before the actuator assemblies are used to actively expand the prosthetic valve. In the other words, the prosthetic valve 308 can have a diameter equal to D1 after it is advanced from the sheath 322. If there is a gap between prosthetic valve 308 and the nosecone 314 when the prosthetic valve is retained in the sheath 322, the gap typically remains after the prosthetic valve is advanced from the sheath 322. In such cases, the gap can make re-crossing the native leaflets difficult.
In some embodiments, a gap between the nosecone and the distal end of the prosthetic valve may form after expansion of a non-mechanical prosthetic valve (e.g., a balloon-expandable or self-expanding prosthetic valve). In some instances, repositioning of these types of valves, after expansion, may be required. However, similarly to as explained above, this gap may make repositioning of these types of prosthetic valves difficult.
Thus, it may be desirable to reduce the gap formation between a fully compressed, or partially or fully expanded prosthetic valve and the nosecone of the delivery apparatus to allow for easier repositioning of the valve without causing injury to a patient's anatomy. As one example, forming a continuity (e.g., a continuous transition) between the nosecone and the distal end of the prosthetic valve, even after partial or full expansion of the valve, may reduce (and in some cases, eliminate) this gap, thereby allowing for easier repositioning of the prosthetic valve at the target implantation site.
For example, in some embodiments, a delivery device (e.g., apparatus) adapted to deliver a prosthetic medical device, such as a prosthetic heart valve, to a target implantation site, may include a transition element adapted to be positioned between a nosecone of the delivery device and the prosthetic medical device, after being deployed from an interior of a sheath of an outer shaft the delivery device. In some embodiments, as shown in
In other embodiments, as shown in
The delivery device 400 further includes an inner shaft 410 with a nosecone 414 mounted on a distal end of the inner shaft 410. The inner shaft 410 extends through an interior of the outer shaft 404.
In some embodiments, the delivery device 400 may also include an intermediate shaft 424 arranged coaxial with and between the outer shaft 404 and the inner shaft 410. The intermediate shaft 424 may be adapted to house and organize one or more actuator assemblies (e.g., actuators) 406. For example, the actuator assemblies 406 may be housed within and extend outwardly from a distal end of the intermediate shaft 424.
The prosthetic valve 408 includes a frame with a proximal end 416 and a distal end 426, the distal end 426 arranged opposite the proximal end 416, in a direction of a central longitudinal axis 418 of the delivery device 400 (and valve). The actuator assemblies 406 may be coupled to the proximal end 416 of the frame of the prosthetic valve 408. The distal end 426 of the frame of the prosthetic valve 408 is arranged proximate to a proximal end 420 of the nosecone (e.g., the proximal end 420 is arranged closer to the distal end 426 than the proximal end 416 of the frame of the prosthetic valve 408).
While the prosthetic valve 408 illustrated in
In some embodiments, as shown in
In some embodiments, the balloon 436 is an inflatable balloon adapted to be inflated from a deflated state (as shown in
In one embodiment, a balloon catheter may be used to inflate and deflate the balloon 436. For example, a balloon catheter may extend through the intermediate shaft 424 and/or inner shaft 410 and fluidly couple to the balloon 436. In another embodiment, an inner lumen of the inner shaft 410 may be used to deliver an inflation fluid (e.g., saline) to the balloon 436 via one or more ports or openings arranged along the inner shaft 410, in a region of the inner shaft 410 that is arranged inside the balloon 436.
As shown in
The balloon 436 may be inflated by an amount that provides this continuous transition between the proximal end 420 of the nosecone 414 and the distal end 426 of the prosthetic valve 408.
In some embodiments, the balloon 436 can be a compliant balloon formed from an elastic material (e.g., polyurethane or silicone). A compliant balloon 436 can be inflated to a desired size within a range of possible sizes based on the size of the prosthetic valve 408. In other embodiments, the balloon 436 can be a semi-compliant balloon formed from a material that is relatively less elastic than materials used for compliant balloons (e.g., Pebax or high-durometer polyurethanes). Similar to a compliant balloon, a semi-compliant balloon can be inflated to a desired size within a range of possible sizes based on the size of the prosthetic valve 408, although it cannot stretch or expand to the extent that a compliant balloon can.
In still other embodiments, the balloon 436 can be a noncompliant balloon formed from a non-elastic material or material with a small amount of elasticity (e.g., polyester or nylon). A noncompliant balloon expands to a predetermined size when fully inflated, which can be selected based on the size of the prosthetic valve with which the balloon will be used.
The inflated balloon 436, as shown in
Once the prosthetic valve 408 is actively expanded (as shown in
In some embodiments, the distal end of the balloon 436 may be attached to the proximal end 420 of the nosecone 414.
In other embodiments, as shown in
As an example, the balloon 436 may be pre-filled with a compressible fluid or other type of compressible material (such as with a hydrogel, which can be in the form of hydrogel beads) to an expanded state and then compressed (to a smaller diameter) to fit within the sheath 422, between the nosecone 414 and the prosthetic valve 408, as shown in
In some embodiments, the shape of the balloon (whether pre-filled or inflated by the user) can be modified by the user by moving the proximal and distal ends of the balloon relative to each other. For example, as shown in
In some cases, as shown in
Extending the length of the balloon 436 to the second length 432 decreases the outer diameter of the balloon 436. In one example, the second length 432 may be chosen so that the largest diameter of the balloon 436 is equal to or slightly less than the outer diameter (e.g., non-actively expanded diameter) of the prosthetic valve 408, as shown in
The dimensions, including the length and filled volume of the balloon may be selected to provide a continuous transition between the proximal end 420 of the nosecone 414 and the distal end 426 of the prosthetic valve 408.
Further, in the embodiments of the pre-filled (non-actively inflatable) balloon 436, the length and filled volume of the balloon may be further chosen to enable retraction of the balloon through the inner lumen of the prosthetic valve 408, at the end of the implantation procedure (e.g., after the valve has been actively expanded and placed in the patient's anatomy).
In another implementation, the balloon 436 can be pre-filled with a liquid (e.g., saline). The balloon can be radially compressed by retracting the pull member 434 proximally and/or advancing the inner shaft 410 distally to reduce the diameter of the balloon 436 until it is equal to or less than D1 and can be stored in the sheath 422 during delivery of the prosthetic valve. At the implantation site, the prosthetic valve 408 and the balloon 436 can be deployed from the sheath 422. The user can then adjust the size of the balloon 436 to create a smooth transition section between the prosthetic valve and the balloon, as depicted in
The pre-filled balloon does not require an inflation/deflation catheter, which may simplify the overall structure of the delivery device 400. In alternative embodiments, the balloon can be pre-filled but can also be configured to receive additional inflation fluid during the implantation procedure to further increase the size of the balloon if needed.
In an alternative embodiment, the configuration shown in
In this way, a balloon (actively inflatable or pre-inflated) of a delivery device may be adapted to be positioned between a nosecone and prosthetic valve, after unsheathing the prosthetic valve from an outer shaft of the delivery device, thereby providing a continuous transition and filling a gap created between the nosecone and the non-compressed prosthetic valve. As a result, the prosthetic valve may be more easily repositioned at the target implantation site, if required, without causing damage to the patient's anatomy and/or the prosthetic valve.
In some embodiments, as shown in
Thus, the compressible element 440 may have an expanded, non-compressed (e.g., resting) state or geometry when not retained within and compressed by the sheath 422 of the delivery device 400 (as shown in
For example, as shown in
The compressible element 440 is configured to expand to its resting (e.g., expanded, non-compressed) state, between the nosecone 414 and the prosthetic valve 408 when the sheath 422 is moved away from and no longer covers the compressible element 440 and the prosthetic valve 408.
For example, as shown in
In
After being fully deployed from the sheath 422 (e.g., arranged outside of the sheath), the compressible element 440 expands to its resting state (also referred to as its expanded, non-compressed state) having a second diameter 450, as shown in
In this way, due to its compressible nature, the compressible element 440 is adapted to passively expand (e.g., without active actuation from an external, actuation source) from its compressed state to its expanded, non-compressed state upon removal from an inside of the sheath 422. This is due to the face that inner walls of the sheath 422 are no longer applying an inward, compression force against an outer surface of the compressible element 440.
As shown in
For example, in some embodiments, the compressible element 440 tapers in diameter from the second diameter 450, at a middle portion of the compressible element 440, to the proximal end 420 of the nosecone 414 and tapers in diameter from the second diameter 450, at the middle portion, to the distal end 426 of the prosthetic valve 408.
In some embodiments, as shown in
In some embodiments, as shown in
In some embodiments, the proximal end 446 (or the proximal-most end 456 in embodiments where the compressible element has the proximal tapered region 452) of the compressible element 440 may be attached to a pull member (not shown in
Due to its compressible nature, the compressible element 440 may compress to a smaller diameter (e.g., smaller than second diameter 450) during removal from the implantation site, at the end of the implantation procedure, and may not disrupt or dislodge the radially expanded and implanted prosthetic valve 408.
In this way, a compressible element (e.g., compressible foam or sponge) of a delivery device may be adapted to be positioned between a nosecone and prosthetic valve, after unsheathing the prosthetic valve from an outer shaft of the delivery device, thereby providing a continuous transition between the nosecone and the partially expanded prosthetic valve. As a result, the prosthetic valve may be more easily repositioned at the target implantation site, if required, without causing damage to the patient's anatomy and/or the prosthetic valve.
In some embodiments, as shown in
As shown in
In some embodiments, the distal end 468 of each of the arms 464 may be coupled to the proximal end 420 of the nosecone 414 via a hinged connection 466. As such, each arm 464 may be configured to pivot about its hinged connection 466 between a compressed state (as shown in
Each arm 464 extends proximally, in the axial direction, towards the prosthetic valve 408, from its distal end 468 to a proximal end 470 of the arm 464. The proximal end 470 of each arm 464 may be a free end that is unattached to another component of the delivery device 400, and thus, is adapted to freely move from the compressed state to the expanded state.
In some embodiments, the arms 464 can be covered by a circumferential flexible cover 472 (shown in
As shown in
Then, when the sheath 422 is removed to uncover the frame 462 (e.g., retracted in the proximal direction, away from the nosecone 414), the frame 462 assumes its expanded configuration, tapering in diameter from the prosthetic valve 408 to the nosecone 414.
For example, as shown in
As shown in
In this way, the mechanical element 460 extends between and forms a continuous transition between the nosecone 414 and the prosthetic valve 408, after the prosthetic valve 408 has been deployed from within the sheath 422 and assumes an at least partially expanded configuration (as shown in
In some embodiments, as shown in
It should be noted that
As shown in
In this way, an expandable mechanical element of a delivery device may be adapted to be positioned between a nosecone and prosthetic valve, after unsheathing the prosthetic valve from an outer shaft of the delivery device, thereby providing a continuous transition between the nosecone and the non-compressed prosthetic valve. As a result, the prosthetic valve may be more easily repositioned at the target implantation site, if required, without causing damage to the patient's anatomy and/or the prosthetic valve.
At 1002, method 1000 includes advancing a delivery device (e.g., delivery device 300 of
At 1004, method 1000 includes, after reaching the target implantation site, retracting (or moving, such as axially moving) the distal end portion of the outer shaft away from the nosecone to uncover the prosthetic valve, which can cause the prosthetic valve to expand to a partially expanded state (e.g., as shown in
At 1006, if required for repositioning (e.g., re-crossing the native valve), the method 1000 includes expanding a transition element of the delivery device in a space formed between the proximal end of the nosecone and a distal end of the prosthetic valve in the partially expanded or fully compressed state. The transition element may include one of the transition elements described herein with reference to
In other embodiments, the transition element is a pre-inflated balloon and expanding the transition element includes passively expanding the pre-inflated balloon from a radially compressed state (as shown in
In yet other embodiments, the transition element is a compressible element including one of a compressible foam and a sponge material and expanding the transition element includes passively expanding the compressible element from a compressed state (as shown in
At 1008, method 1000 optionally includes (e.g., if required by the procedure due to inaccurate positioning), after expanding the transition element, repositioning the prosthetic valve, in the partially expanded state or fully compressed state, at the target implantation site via adjusting a component of the delivery device. The more continuous transition provided by the transition element, between the nosecone of the delivery device and the prosthetic valve, may enable easier maneuvering of the valve in the distal or proximal directions during repositioning, without causing degradation to the patient's anatomy and/or the prosthetic valve.
At 1010, method 1000 includes, after repositioning the prosthetic valve, or after positioning the prosthetic valve (without repositioning), actively expanding, in a radial direction, the prosthetic valve to a radially expanded state. For example, actively expanding the prosthetic valve may include actuating one or more actuator assemblies (e.g., actuator assemblies 306 shown in
At 1012, method 1000 includes retracting the nosecone and transition element of the delivery device away from the implantation site, in the proximal direction, and removing the delivery device from the body of the patient. In some embodiments, the method at 1012 may include compressing the transition element to a geometry (e.g., diameter) that is smaller than its diameter in the expanded state. For example, if the transition element is an inflatable balloon, the method at 1012 may include deflating the balloon and then retracting the nosecone and balloon, in the proximal direction, through an inner lumen of the prosthetic valve. In another example, if the transition element is a compressible element (such as a compressible foam or sponge), the method at 1012 may include pulling the nosecone and compressible element in the proximal through the inner lumen of the prosthetic valve and passively compressible the compressible element to a radially smaller state (e.g., via pressure against the inner lumen of the prosthetic valve). In yet another example, if the transition element is a mechanical element with an expandable (and compressible) frame, the method at 1012 may include re-compressing the mechanical element to its compressed state via a compression mechanism (as shown in
In this way, the more continuous transition between an at least partially expanded or fully compressed prosthetic valve (e.g., after being removed from a sheath of a delivery device) and a nosecone of the delivery device provided by one of the transition elements described herein may allow for easier repositioning of the prosthetic valve at or proximate to the target implantation site within a body of a patient. For example, an at least partially expanded or fully compressed prosthetic valve may be more easily moved in a distal and/or proximal direction, relative to a target implantation site, to reposition the prosthetic valve before fully expanding and implanting the prosthetic valve at the target implantation site, without causing damage to the body of the patient and/or the prosthetic valve, when the transition element is utilized. Further, by having a compressible or actively expandable and compressible transition element, the transition element may be stored in a compressed state within an interior of an outer shaft of the delivery device during maneuvering of the delivery device to the target implantation site and then expanded to its expanded, non-compressed state after uncovering of the prosthetic valve from the distal end of the outer shaft, thereby forming the more continuous transition in a space formed between the uncovered prosthetic valve and the nosecone. The compressible transition element may then be re-compressed, prior to removal of the delivery device from the implantation site, through the inner lumen of the expanded prosthetic valve, thereby enabling easier removal that does not disturb or dislodge the implanted prosthetic valve.
It should be understood that the disclosed embodiments can be adapted to deliver and implant prosthetic devices in any of the native annuluses of the heart (e.g., the pulmonary, mitral, and tricuspid annuluses), and can be used with any of various delivery approaches (e.g., retrograde, antegrade, transseptal, transventricular, transatrial, etc.).
For purposes of this description, certain aspects, advantages, and novel features of the embodiments 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 embodiments, 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 embodiments require that any one or more specific advantages be present or problems be solved. The technologies from any example can be combined with the technologies described in any one or more of the other examples. In view of the many possible embodiments to which the principles of the disclosed technology may be applied, it should be recognized that the illustrated embodiments are only preferred examples and should not be taken as limiting the scope of the disclosed technology.
Although the operations of some of the disclosed embodiments 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 herein, with reference to the transcatheter delivery system, the prosthetic heart valve, the delivery device, the delivery apparatus, and the transition element, “proximal” refers to a position, direction, or portion of a component that is closer to a handle of the delivery system that is outside the patient, while “distal” refers to a position, direction, or portion of a component that is further away from the handle (and farther into a body of the patient). The terms “longitudinal” and “axial” refer to an axis extending in the proximal and distal directions, unless otherwise expressly defined.
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 “connected” 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.
Directions and other relative references (e.g., inner, outer, upper, lower, etc.) may be used to facilitate discussion of the drawings and principles herein, but are not intended to be limiting. For example, certain terms may be used such as “inside,” “outside,”, “top,” “down,” “interior,” “exterior,” and the like. Such terms are used, where applicable, to provide some clarity of description when dealing with relative relationships, particularly with respect to the illustrated embodiments. Such terms are not, however, intended to imply absolute relationships, positions, and/or orientations. For example, with respect to an object, an “upper” part can become a “lower” part simply by turning the object over. Nevertheless, it is still the same part and the object remains the same. As used herein, “and/or” means “and” or “or,” as well as “and” and or.
In view of the many possible embodiments to which the principles of the disclosed invention may be applied, it should be recognized that the illustrated embodiments are only preferred examples of the invention and should not be taken as limiting the scope of the invention. Rather, the scope of the invention is defined by the following claims. We therefore claim as our invention all that comes within the scope and spirit of these claims.
This application is a continuation of PCT Patent Application No. PCT/US2020/055546, entitled “EXPANDABLE TRANSITION ELEMENT FOR A TRANSCATHETER DELIVERY DEVICE,” filed Oct. 14, 2020, which claims the benefit of U.S. Provisional Application No. 62/928,973 entitled “EXPANDABLE TRANSITION ELEMENT FOR A TRANSCATHETER DELIVERY DEVICE,” filed Oct. 31, 2019, all of which are incorporated by reference herein in their entirety.
| Number | Date | Country | |
|---|---|---|---|
| 62928973 | Oct 2019 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/US2020/055546 | Oct 2020 | US |
| Child | 17732185 | US |
