Patent Application
20060259118
The present invention relates to medical devices generally used percutaneously or through a delivery apparatus (such as an endoscope) for the delivery of self-expanding devices, as well as methods of making and using such devices.
This invention relates generally to medical devices and, in particular, to a delivery system that employs a catheter device for use with self-expanding devices such as stents, prosthetic valve devices, and other implantable articles at a selected location inside a patient's body. More particularly, the device includes a flexible, kink-resistant middle section having an outer sheath and inner compression member and having a distal end comprising an inner guide channel member and an outer guide channel member, the inner and outer guide channel members being configured to facilitate rapid insertion of a wire guide and delivery of self-expanding devices.
Self-Expanding Devices
Medical delivery and placement systems and tools have grown out of the need for implanting medical devices in endovascular and other body lumens of a patient. The present invention relates to new and useful medical devices generally used percutaneously or through an apparatus such as an endoscope for delivering a particular type of implantable medical devices: self-expanding devices. Types of self-expanding devices include various medical devices, such as stents, prosthetic valve devices, and other implantable articles for placement inside a patient's body. Although use of the present invention is not limited to stents, a discussion of stent technology provides a general and beneficial introduction into the variety of self-expanding devices that the present invention delivers and places in endovascular and other body lumens.
Minimally invasive surgical stent technology has become popular since the introduction of stents to the medical device market in the United States in the early 1990s. For more than a decade, stents have proven to provide an excellent means for maintaining vessel patency, and have become widely accepted in the medical field.
By way of background, stents are configured to be implanted into body vessels having a passageway in order to reinforce, support, repair, or otherwise enhance the performance of the passageway. The term “passageway” is understood to be any lumen, channel, flow passage, duct, chamber, opening, bore, orifice, or cavity for the conveyance, regulation, flow, or movement of bodily fluids and/or gases of an animal. As an example, stents have been used in the passageways of an aorta, artery, bile duct, blood vessel, bronchiole, capillary, esophagus, fallopian tube, heart, intestine, trachea, ureter, urethra, vein, and other locations in a body (collectively, “vessel”) to name a few.
Depending on the vessel in which it is to be implanted, a stent may come in a variety of different configurations. In general, a stent may comprise a ring, or stack of rings, each ring being formed of struts and apices connecting the struts, whereby the stent defines an approximately tube-like configuration. Furthermore, the stent perimeter, when viewing the stent end-on, may define a structure roughly, but not exactly, resembling a round cylinder if the struts are straight, because the struts follow a straight line from the apex on one end of the strut to the apex on the other end of the strut.
In addition to their having a variety of configurations, stents also come in different types as defined by the way they expand. For instance, various types of expandable stents have been described that are self-expanding, balloon-expandable, or a combination thereof where the stent is partially self-expanding and partially balloon-expandable. Expandable stents are normally evaluated, more or less, with respect to four performance criteria: the radially outward expansile force that the stent exerts in the vessel passageway on an interior surface of the vessel; the small diameter to which the stent is capable of being compressed for the insertion procedure; the ability of the stent to traverse curved passageways; and the stability of the stent in being resistant to migrating from its originally implanted position.
A balloon-expandable stent is generally mounted on an expandable member, such as a balloon, provided on the distal end of a delivery system, such as a catheter or tubular delivery device, to be discussed more fully below. In operation, a physician or other healthcare professional (collectively, “physician”) inserts the catheter into and navigates the catheter through a vessel passageway by advancing the catheter to a desired location adjacent the target site within the vessel passageway of a patient. In a subsequent step, the physician pulls back a sheath or other covering member to withdraw from and releasably expose the stent for deployment. In another step, the physician inflates the balloon to plastically deform the stent into a substantially permanent expanded condition. The physician then deflates the balloon and removes the catheter or delivery device from the patient's body.
For a self-expanding stent, the stent is resiliently compressed into a collapsed first, smaller diameter, carried by the delivery system, and due to its construction and material properties, the stent expands to its second, larger diameter upon deployment. In its expanded configuration, the stent exhibits sufficient stiffness so that it will remain substantially expanded and exert a radially outward force in the vessel passageway on an interior surface of the vessel.
One particularly useful self-expanding stent is the Z-stent, introduced by Cook Incorporated, due to its ease of manufacturing, high radial force, and self-expanding properties. Examples of the Z-stent are found in U.S. Pat. Nos. 4,580,568; 5,035,706; 5,282,824; 5,507,771; and 5,720,776, the disclosures of which are incorporated in their entirety. The Zilver stent, introduced by Cook Incorporated, is another particularly useful self-expanding stent due to its nitinol platform and use of the Z-stent design properties. Examples of the Zilver stent are found in U.S. Pat. Nos. 6,743,252 and 6,299,635, the disclosures of which are incorporated in their entirety. By way of example only, one or more of these designs have been utilized in stents for applications involving the bronchioles, trachea, thoracic aortic aneurysms (stent-graft), abdominal aortic aneurysms (stent-graft), intestines, biliary tract, and prosthetic venous valve devices. The Z-stent and Zilver stent are capable of being compressed, inserted into a catheter or delivery device, pushed out into the passageway of a vessel, and then self-expanded to help keep the vessel passageway in an open state. A few of the embodiments of devices using one of these stents are the Zilver® 518 biliary self-expanding stent and the Zenith® AAA Endovascular Graft for the endovascular treatment of an abdominal aortic aneurysm.
A stent of the self-expanding type, like the balloon-expandable type, may assume a collapsed tubular configuration having a smaller diameter and an expanded tubular configuration having a larger diameter. In its collapsed smaller diameter configuration, the stent can be constrained by a delivery system in order to be positioned in the vessel passageway where desired. The stent is then deployed by the delivery system and expanded.
In both the self-expanding and balloon-expandable types of stents (and combinations thereof), a delivery system for percutaneous positioning of the stents in the vessel passageway may use a wire guide. The physician uses the wire guide to maneuver a portion of the delivery system through the vessel passageway and to the desired position therein.
Wire Guide
A wire guide can be used to place a delivery system, such as a catheter or tubular delivery device, into a vessel passageway percutaneously. A physician may use a cannula or a needle as a way of introducing the wire guide. For instance, the physician may create an incision in the patient and then position the cannula in the incision for the insertion of the wire guide. The typical wire guide has proximal and distal ends. A physician inserts the distal end into the proximal end of the cannula or needle and then out a distal end of the cannula or needle, and thus into the vessel passageway. Once inside the vessel, the wire guide may be advanced and manipulated until the distal end of the wire guide reaches its destination. Alternatively, the physician may place the cannula or needle into any one of a variety of vessels, such as an artery, bile duct, brachial vein, cephalic vein, or other vessel as described above, and then may introduce the wire guide through the needle into the vessel. In subsequent steps, the physician may withdraw the needle over the wire guide and introduce a guide catheter over the wire guide and into the patient.
Regardless of how the physician places the wire guide into a vessel passageway for use with a traditional delivery system, the physician must ensure that the catheter or other medical device has the right length relative to the length of the wire guide. Consequently, the catheter or other medical device will be inserted over the wire guide to a precise length inside the patient so that a distal end of the catheter or other medical device is positioned at or near the distal end of the wire guide in proximity to a target site for treatment, diagnosis, or medical intervention. However, a long, straightened portion of the wire guide will remain outside of the patient's body and may get caught on outside objects and disturb the placement of the catheter.
Additional procedures that involve wire guides often require exchanging of catheters or medical devices. For example, a catheter may be used for the delivery of a self-expanding device such as a stent. In that case, the stent may be deployed, the catheter withdrawn and reloaded with an additional stent or replaced with a separate catheter carrying another stent, or even exchanged for a different medical device. This procedure may prove cumbersome and time consuming, because as explained below, the overall length of a wire guide in an over-the-wire delivery system needs to be substantially longer than the length of the delivery catheter (e.g., the wire guide may need to be twice as long as the catheter). Furthermore, the proximal portion of the wire guide outside the patient's body must remain a sterile field, but as explained below, when the wire guide needs removing or the catheter exchanging for another catheter or other medical device, then an additional person in the operating room needs to hold onto the proximal end of the wire guide to keep the wire guide straight and to prevent unintended proximal or distal movement of the wire guide.
Catheter
Many delivery systems employ a catheter, sheath, cannula, introducer, or other medical delivery device or tube-like structure, which must “slide over” the wire guide yet fit “within” a guide catheter or a working channel of an endoscope or an external accessory channel device used with an endoscope (individually and collectively, “catheter”). The catheter comprises a lumen for the wire guide. Generally stated, these delivery systems may fall within two categories. The first category of delivery systems to have been used, and consequently the first to be discussed below, is commonly referred to as an “over-the-wire” catheter system. The other category of delivery systems is sometimes referred to as a “rapid exchange” catheter system. In either system, a wire guide is used to position the delivery system within a vessel passageway. The typical wire guide has proximal and distal ends. A physician inserts the distal end into the vessel passageway, advances, and maneuvers the wire guide until the distal end reaches its desired position within the vessel passageway.
In the “over-the-wire” catheter delivery system, a physician places the catheter over the wire guide, with the wire guide being received into a lumen that extends substantially through the entire length of the catheter. In this over-the-wire type of delivery system, the wire guide may be back-loaded or front-loaded into the catheter. In front-loading an over-the-wire catheter delivery system, the physician inserts the distal end of the wire guide into the catheter's lumen at or near the catheter's proximal end. In back-loading an over-the-wire catheter delivery system, the physician inserts a distal portion of the catheter over the proximal end of the wire guide. The back-loading technique is more common when the physician has already placed the wire guide into the patient, which is typically the case today. In either case of back-loading or front-loading an over-the-wire catheter delivery system, the proximal and distal portions of the catheter will generally envelop the length of the wire guide that lies between the catheter first and second ends. While the wire guide is held stationary, the physician may maneuver the catheter through the vessel passageway to a target site at which the physician is performing or intends to perform a treatment, diagnostic, or other medical procedure.
Because this delivery system fits over the wire guide, the replacement or exchange of catheters or medical devices requires that the portion of the wire guide protruding from the patient's body be longer than the replacement or exchanged catheter or medical device. For instance, if 60 centimeters (cm) of the catheter is to be inserted into the patient, then a wire guide will need to be slightly longer than approximately 120 cm, because the physician will need to hold or secure the proximal portion of the wire guide (i.e., the portion extending out of the body) as the delivery catheter is being back-loaded onto the wire guide. Consequently, the overall length of the wire guide may need to be at least more than 120 cm. Likewise, replacement or exchange of a catheter or medical device requires that a physician secure the proximal end of this lengthy wire guide while the catheter is withdrawn from the patient until the distal end of the catheter is then slipped off of the proximal end of the wire guide. This procedure requires a considerable operational time when the catheter is initially placed over the wire guide for insertion into the patient and is withdrawn from the wire guide for exchange or replacement. Furthermore, the extra wire guide length makes control and manipulation of the wire guide difficult, cumbersome, and usually requires an extra person in the sterile field of the procedure to help control and protect the proximal end of the wire guide.
Therefore, there is a need for an apparatus that enables a user to quickly and easily advance a catheter over a wire guide. The present invention solves these and other problems.
Another problem with conventional over-the-wire delivery systems is tendency for the stent-carrying inner catheter to kink during stent deploment. It should be understood in conceptual terms how self-expanding devices (such as stents, prosthetic valve devices, and other implantable articles) are generally deployed from the delivery system. Using a self-expanding stent as an example, inner and outer catheters are utilized for delivering the implantable stent to a deployment site well within the vessel passageway of the patient. The stent is releasably positioned on a platform located at the distal end of a stent-carrying inner catheter. On the platform, the stent is seated axially intermediate optional distal and proximal radiopaque restraint markers and sandwiched transversely (i.e., compressed) between the outer catheter and the inner catheter.
Typically (using the self-expanding stent for illustration), the stent-constraining outer catheter is withdrawn proximally over the stent. As is conventional, “distal” means away from the physician when the device is inserted into a patient, while “proximal” means closest to or toward the physician when the device is inserted into a patient. The outer catheter and inner catheter must be flexible enough to navigate a vessel passageway. In particular, the inner catheter may be susceptible to kinking when the stent-constraining outer catheter is withdrawn to deploy the self-expanding device, because the self-expanding device exerts friction and drag on the interior surface of the stent-constraining outer catheter, owing to the self-expanding device's radially outward expansile force property as discussed above. Thus, the self-expanding device and the stent-carrying inner catheter will be prone to withdraw together with the stent-constraining outer catheter. As a result, the inner catheter may be prone to kink upon withdrawal of the outer catheter.
Therefore, there is a need for an apparatus that enables the user to withdraw the stent-constraining outer catheter proximally over the stent without causing the stent-carrying inner catheter to move proximally or to kink. The present invention solves these and other problems.
The present invention has enough flexibility to navigate through the vessel passageway with an outer catheter, and an inner compression member has sufficient stiffness to “push” the stent in order to counter the urge for the stent (or a stent-carrying catheter) to prolapse proximally with the withdrawing of the outer guide channel member. As will be understood, “pushing” on the inner compression member will keep a stent-carrying inner catheter (and therefore the stent) from translating as a result of an outer catheter being pulled over the stent; thereby “pushing” holds the stent in place at the desired deployment site within the patient's body.
Another aspect of the present invention is to design the inner compression member so that it optionally has a dual functionality. For instance, in addition to being a flexible and sufficiently stiff member to resist kinking during stent deployment, the inner compression member in one embodiment also carries and removes fluids, where the term “fluid” is understood as including but not limited to gases, air, water, contrast fluid, oil, saline solution, blood sample, flushing solution, medication, drug eluting therapeutic substance, or other liquid, gas, fluid, or medium that is biocompatible or capable of being made biocompatible.
Turning now to a delivery system that is sometimes referred to as a “rapid exchange delivery system,” the traditional rapid exchange delivery system may be prone to the same susceptibility of kinking as discussed above and, additionally, may be prone to kink the wire guide as explained below. Like the over-the-wire delivery system, the conventional rapid-exchange system utilizes an outer catheter and an inner catheter, which are substantially co-axial. The conventional rapid-exchange delivery system further comprises a distal segment with a stent-carrying inner member. Unlike the over-the-wire system where the wire guide is received into the lumen of the inner catheter and extends the entire length of the inner catheter, in the rapid exchange delivery system the wire guide occupies a catheter lumen extending only through the distal segment of the outer catheter.
With respect to the distal segment of the outer catheter in a traditional rapid exchange delivery system, the wire guide enters a distal section and, in particular, a lumen of a stent-carrying inner catheter at a distal opening and exits the stent-carrying inner catheter at a side opening proximal to the distal opening. The wire guide in the conventional rapid exchange system bends substantially and diverges significantly away from the longitudinal axis of the stent-carrying inner catheter as it converges toward an exit side port located in an outer wall of a stent-constraining outer catheter. Thus, the wire guide enters the delivery system at the distal portion of the inner catheter, exits the side opening in the inner catheter and the side port of the outer catheter, and then runs proximally along the outside surface of the outer catheter wall and is substantially parallel with or “side-by-side” with the inner catheter.
The bend that the wire guide goes through, in the traditional rapid exchange system, as it passes from the lumen of a stent-carrying inner catheter to the exit side port in the outer wall of the stent-constraining outer catheter proximately causes and contributes to added resistance (compared to a wire guide experiencing substantially no or considerably reduced bending). For instance, the wire guide turns significantly away from the longitudinal axis of the lumen of the stent-carrying inner catheter when the physician withdraws the outer catheter proximally to remove, replace, or exchange the delivery system with a new catheter containing another self-expanding stent or a different medical device. As a result of its bending, the wire guide tends to kink. A kink in the wire guide may cause difficulty during a later step where, after the stent is deployed, the outer catheter during withdrawal catches on the wire guide kink and pulls the distal end of the wire guide away from the deployment site. Also, after the delivery system is withdrawn from the proximal end of the wire guide, the inner catheter may need to be reloaded onto the wire guide (e.g., with an additional stent, or replaced with a catheter carrying a different medical device) and will then encounter the wire guide kink as the inner catheter moves distally.
Buckling and bowing, as two forms of kinking, of the distal segment of the device may occur with a traditional design of a rapid exchange delivery system in the vicinity where the wire guide exits the inner catheter side opening and turns substantially transverse to the inner catheter in order to leave the side exit port of the relatively juxtaposed proximal opening in the stent-carrying member and the side port in the outer wall of the stent-constraining outer catheter. Owing to the transverse position of the side opening in the outer wall of the stent-carrying inner catheter and the transverse side exit port in the outer wall of the stent-constraining outer sheath, there is an open cutout profile in the traditional device that may have a tendency to buckle or bow at the cutout when traversing within the narrow confines of the vessel passageway. The tendency to buckle or bow may decrease with a closure of the cutout by elongating the exit side port in the outer wall of the stent-constraining outer catheter, but this may cause weakness in pull strength or bending properties of the outer catheter. Indeed, the outer catheter and the stent-carrying inner catheter are basically of thin-wall construction: while increasing the thickness of the walls at the location of the inner catheter side opening and the outer catheter exit side port minimally improves the level of resistance to buckling or bowing, this level is still often considered unacceptable. In addition, increasing the thickness of the walls is generally considered undesirable because it necessitates the use of a larger delivery device or entry hole in the patient than would otherwise be required (owing to the increased profile of the catheter). Furthermore, the larger catheter profile may also cause unnecessary irritation of the patient's vessel, as well as limiting the size of the vessel in which the delivery system may operate.
The present invention solves these and other problems by providing a breech position opening.
Another challenge with the traditional design of a rapid exchange delivery system is proper alignment of the stent-carrying inner catheter side opening and the exit side port of the stent-constraining outer catheter. Misalignment may occur during several steps. For instance, the stent-carrying inner catheter and the stent-constraining outer catheter may rotate or their relative axial positions may shift during navigation and positioning of the delivery system through the vessel passageway. Another example where misalignment may occur is during the withdrawal of the stent-constraining outer catheter. As the outer catheter retracts proximally from the relative position of the stent-carrying inner catheter to expose and to deploy the stent from the stent-carrying platform, misalignment may result. Increasing the size of the exit side port of the stent-constraining outer catheter alleviates some of the alignment challenges but further increases the problems of kinking, buckling, bending, and bowing as discussed above.
Thus, during positioning, operation, repeated use, or patient movement, the stent-constraining outer catheter may be bent or shifted axially or rotationally, thereby resulting in a kink in the sheath or misalignment of the side opening of the stent-carrying inner catheter and the side exit port of the outer catheter's outer wall. A kinked or misaligned catheter may become unusable and, even if useable may be difficult to straighten while positioned in the body of a patient. Consequently, the sheath must be manipulated within the patient's vessel passageway, giving rise to an increased duration in the medical procedure. Alternatively, the delivery system may need to be removed, leaving an enlarged, bleeding opening which typically cannot be reused. Vascular access must then be re-attempted at an alternative site, and the procedure restarted. This can cause an unnecessary delay of time and, during emergency procedures, may be life threatening. In addition, in some cases, an acceptable alternative site is not available for introducing another delivery device.
The present invention solves these and other problems by providing a transition region for an inner guide channel member and an outer guide channel member.
Therefore, it would be desirable to have a medical device delivery system for self-expanding devices such as stents, prosthetic valve devices, and other implantable articles inside a patient's body, whereby a flexible, kink-resistant middle section delivery device has an outer sheath and an inner compression member, and a distal end of the device comprises an outer guide channel member and inner guide channel member that comprise a cooperatively kink-resistant wire guide lumen configured to facilitate rapid insertion of a wire guide and delivery of a self-expanding device. Consequently, it is desirable to have medical systems and rapid insertion delivery devices for the delivery of self-expanding devices as taught herein, and methods of making and using such devices.
The present invention provides medical device delivery systems for the rapid insertion of medical devices.
In one embodiment, an inner guide channel member has a first end portion having an entry port and a second end portion having an exit port and a guide channel therebetween and having an outer surface for a stent platform intermediate the first and second end portions. A proximal stent restraint is disposed about and operatively coupled to the inner guide channel member intermediate the inner guide channel member first and second end portions, and the stent platform distal the proximal stent restraint and proximal the inner guide channel member entry port. An outer guide channel member has first and second end portions defining a channel therebetween for receiving the inner guide channel member second portion, wherein the guide channels are substantially aligned.
In another embodiment, an inner guide channel member has a first end portion with an entry port and a second end portion with an exit port and defining a channel therebetween and having a stent platform intermediate the ports. An outer guide channel member has first and second portions defining a channel sized to slidably receive the inner guide channel member second end portion. The outer guide channel member has a stent constraining surface disposed about the inner guide channel member stent platform, and has a stepped profile with a first outer diameter intermediate the outer guide channel member first and second end portions, and a second smaller outer diameter near the outer guide channel member exit port. The exit ports are in fluid communication.
In still another embodiment, the delivery apparatus includes a system proximal portion having a handle and stylet. A middle section delivery device has an elongate outer sheath operatively coupled to the handle, and an elongate inner compression member having a proximal end and a distal mating end portion, the inner compression member proximal end being operatively coupled to the stylet. A system distal portion has an inner guide channel member with a first and second end portion defining a channel, an outer guide channel member axially slidably receiving the inner guide channel member second end portion. The outer guide channel member has an entry port and an exit port defining a guide channel therebetween, and a stepped profile having a first outer diameter intermediate the outer guide channel member first and second end portions and a second smaller outer diameter located at or near the outer guide channel member second end portion. The system distal portion and middle section delivery device are operatively coupled.
In still another embodiment, methods of using a delivery apparatus for the rapid insertion of medical devices for intracorporeal procedures are provided. A delivery system is provided having a system proximal portion having a handle and a stylet and intended to remain outside a patient, a middle section delivery device having an outer sheath and an inner compression, and a system distal portion having an inner guide channel member and an outer guide channel member having a stepped profile, the system distal portion further comprising a self-expanding deployment device mounting region, a transition region, and a proximal breech opening. A self-expanding device is loaded into a radially compressed state at the stent mounting region. The system distal portion is slide over a previously positioned guiding device. The outer guide channel member is retracted proximally relative to the inner member so as to deploy the self-expanding device.
The present invention relates to medical devices, and in particular to a delivery system configured for rapid insertion delivery of self-expanding devices such as stents, prosthetic valve devices, and other implantable articles inside a patient's body. For conciseness and ease of description of the embodiments of the invention, the term “stent” and its variations shall refer individually and collectively (without limiting the invention) to all self-expanding devices used with the invention, such as stents, prosthetic valve devices, and other implantable articles inside a patient's body. For the purposes of promoting an understanding of the principles of the invention, the following provides a detailed description of embodiments of the invention as illustrated by the drawings as well as the language used herein to describe the aspects of the invention. The description is not intended to limit the invention in any manner, but rather serves to enable those skilled in the art to make and use the invention. As used herein the terms comprise(s), include(s), having, has, with, contain(s) and the variants thereof are intended to be open ended transitional phrases, terms, or words that do not preclude the possibility of additional steps or structure.
In
System Proximal Portion 12
In the embodiment shown in
The handle 30 comprises any tubular structure having a distal aperture 30″ and a proximal aperture 30′, the apertures defining a chamber 31 therebetween. In general, the handle 30 is a component, instrument, mechanism, tool, device, apparatus, or machine configured for directly or indirectly retracting an outer guide channel member (discussed below) of the distal portion 13 of the device to expose and, ultimately, to deploy a stent at a selected location inside a patient's body.
The handle 30 is axially slideable relative to an elongate (long) inner compression member 41 that comprises a proximal end 40 and a middle section 40′. As discussed more fully below, the inner compression member 41 helps to keep the stent from moving proximally with proximal movement of the handle 30, which handle movement causes the outer guide channel member to withdraw proximally over the stent in order to expose and thereby to deploy the stent. Thus, the inner compression member helps to “push” the stent or stent carrying inner guide channel member in order to counter the urge for the stent or stent carrying member to prolapse proximally with the withdrawing of the outer guide channel member. As will be understood, “pushing” on the inner compression member will keep the stent carrying inner guide channel member (and therefore the stent) from translating as a result of an outer sheath or outer guide channel member being pulled over the stent; thereby “pushing” holds the stent in place at the desired deployment site within the patient's body. In one embodiment, the handle 30 is a unidirectional handle that is axially slideable relative to the inner compression member 41 and/or the optional pusher stylet 20 in order to deploy a stent. In one embodiment, the inner compression member 41 is secured to a pusher stylet 20.
As shown in
The stylet 20 is optional, because in an alternative embodiment the physician may hold the inner compression member proximal end 40′ directly in order to “push” (e.g., hold substantially stationary) the stent carrying inner guide channel member (and therefore the stent). This controls the stent carrying inner guide channel member and stent from translating as a result of an outer sheath or outer guide channel member being pulled over the stent, so that the stent remains at the desired deployment site within the patient's body. Alternatively, the stylet 20 is any stationary handle secured to the inner compression member 41 for achieving the “pushing” (e.g., hold substantially stationary) of the stent or stent carrying inner guide channel member while the outer sheath or outer guide channel member are moved proximally.
The stylet distal end 20″ is housed within the handle chamber 31 and is flared or otherwise flanged sufficiently to be larger than the handle proximal aperture 30′ so as not to pull out of the chamber 31. In one embodiment, the stylet distal end 20″ is secured to the distal portion of the stylet cannula 23, while in another embodiment the stylet distal end 20″ is formed integral with the distal portion of the stylet cannula 23. Consequently, the stylet distal end 20″ functions as a proximal stop that prevents the stylet cannula 23 from backing all the way out the handle while being axially slideable within the handle chamber 31. Thus, the stylet 20 will not slide off the handle 30, if so desired. The stylet distal end 20″ may also, in one embodiment, function as a distal stop against a restraint 33 formed in the handle chamber 31 intermediate the handle proximal and distal apertures 30′, 30″, respectively, where intermediate should be understood to be any position between, and not necessarily equidistant to, the handle apertures 30′, 30″. As a result of the stylet distal end 20″, the handle 30 may slide axially the distance separating the handle restraint 33 and the stylet distal end 20″, which has a maximum distance of when the stylet distal end 20″ is abutting the handle proximal aperture 30′.
A threaded tapered plug 21 and threaded tapered receptacle 22 optionally secure the inner compression member proximal end 40. In one embodiment, the inner compression member proximal end 40 is flared. Securing material 28, such as glue, adhesives, resins, welding, soldering, brazing, chemical bonding materials or combinations thereof and the like (collectively and individually, “glue”) may be used to keep the threaded tapered plug 21 from backing out of the threaded tapered receptacle 22. A portion of the cannula 23 and stylet distal end 20″ are received within the handle chamber 31 distal to the handle proximal aperture 30′ as previously explained.
By optionally placing the inner compression member proximal end 40 in mechanical communication with the plug 21 and receptacle 22, the gripping and “pushing” (e.g., hold substantially stationary) on the stylet 20 (e.g., the receptacle 22) thereby helps to keep the inner compression member 41 from moving away from the distal portion 13 and, accordingly, counters the tendency for a stent or stent carrying member to move proximally during withdrawal of the outer guide channel member as will be explained below. Of course, the inner compression member may be secured elsewhere by the stylet 20, such as at or near the stylet distal end 20″ or intermediate the stylet proximal and distal ends 20′, 20″, respectively, and the stylet distal end 20″ may extend to a position at or near the distal end aperture 30″ of the handle 30.
In addition to holding a threaded tapered plug 21 and optionally the proximal end 40 of the inner compression member 41, the threaded tapered receptacle 22 may secure the proximal portion of the optional cannula 23. Glue 28′ may be used at or near an interface of the cannula 23 and distal aperture of the threaded tapered receptacle 22. The glue 28′ serves many functions, such as to keep dust from settling within the threaded tapered receptacle 22, to make the cannula 23 easier to clean, and to give aesthetics and a smooth feel to the device.
The handle 30 slidably receives the distal portion of the cannula 23 within the handle aperture 30′ and handle chamber 31. As a result, the handle 30 is slidable relative to the stylet 20 (e.g., slidable relative to the threaded tapered plug 21, threaded tapered receptacle 22, and the cannula 23). In use, the physician grips the handle 30 in one hand and grips the stylet 20 (e.g., the receptacle 22) in the other hand. The physician holds the stylet 20 relatively stationary, which prevents the inner compression member and inner guide channel member and its stent carrying portion from moving proximally, and then withdraws the handle 30 proximally relative to the stationary stylet 20 and inner compression member 41. As a result, the physician is thereby retracting an outer guide channel member (discussed below) of the distal portion 13 of the delivery system 10 to expose and, ultimately, to deploy a stent locatable at the distal portion 13 of the delivery system 10. The handle 30 is in communication with—directly or indirectly through intervening parts—the outer guide channel member at the distal portion 13.
As shown in
The handle 30 and check flow body 38 operatively couple with the handle distal aperture 30″ receiving a check flow body proximal mating end 38″ and being secured together by any suitable means, including but not limited to a crimp, friction fit, press fit, wedge, threading engagement, glue, adhesives, resins, welding (laser, spot, etc.), soldering, brazing, adhesives, chemical bonding materials, or combinations thereof. In one embodiment, the handle 30 comprises a coupling member 32 and the check flow body proximal mating end 38″ comprises a coupling member 32′, the coupling members 32, 32′ being complementary to hold the handle 30 and check flow body proximal mating end 38″ together. In one embodiment, the coupling members 32, 32′ may form complementary threads. If it is desired to achieve quicker assembly for manufacturing purposes, then the coupling members 32, 32′ may be an array of circumferential ridges that form an interference fit when pressed together. If a one-time snap fit is desired, then the coupling members 32, 32′ may be circumferential ridges in the form of barbs. In another embodiment, the handle 30 and check flow body proximal mating end 38″ may be put together and taken apart for servicing, in which case the coupling members 32, 32′ may be circumferential ridges in the form of knuckle threads (e.g., circumferential ridges forming complementary undulating waves). The operatively coupled handle 30 and check flow body proximal mating end 38″ according to these embodiments may be fixed such that they do not rotate relative to each other, or may rotate while preventing undesired axial separation.
During use, the detachable cap 39 may be detached or opened and the device flushed with saline to remove air in order to help keep air out of the patient. The intermediate seal 37 and the second seal 37′ ensure that any flushed fluid moves distally in the device and does not back up into the handle 30, such as between the handle restraint 33 and the first bushing 36, into the handle chamber 31, or out the handle proximal aperture 30′. The detachable cap 39 (such as a Luer cap) keeps saline from backing out of the check flow body 38, air from flowing into the check flow body 38, and blood from rushing out during periods of high blood pressure inside the patient.
The medical device delivery systems 10 may be used to deploy an implantable prosthesis that is a balloon expandable or self-expanding stent, prosthetic valve device, or other implantable articles provided on the distal portion of a delivery system. In operation, a physician inserts the distal portion and at least a portion of the middle section delivery device into a vessel passageway, and advances them through the vessel passageway to the desired location adjacent the target site within the vessel passageway of a patient. In a subsequent step, the physician moves the handle proximally, which withdraws the outer sheath and/or the outer guide channel member and releasably exposes the stent for deployment. In another step, the physician inflates the expandable member, such as a balloon, positioned under the stent inner surface to plastically deform the stent into a substantially permanent expanded condition. The physician may inflate the expandable member by injecting fluid such as saline from a syringe into the inner compression member 41, via pusher stylet 20, through a Luer fitting at the proximal end 20′. Therefore, the fluid is directed distally to the expandable member, filling the expandable member chamber and expanding the stent. The physician then deflates the balloon and removes the catheter or delivery device from the patient's body.
In one embodiment as shown in
The check flow body distal mating end 38′ and connector cap 39′ may be operatively coupled mechanically, chemically, and/or chemical-mechanically. In one embodiment, the connector cap 39′ is crimped, friction fitted, press fitted, and/or wedged into engagement onto the check flow body distal mating end 38′. In another embodiment for example, the check flow body distal mating end 38′ and connector cap 39′ are operatively coupled by glue, adhesives, resins, welding (laser, spot, etc.), soldering, brazing, adhesives, chemical bonding materials, or combinations thereof.
According to
According to one embodiment shown in
More particularly,
By way of example only and not by way of limitation, the terms “operatively coupling,” “operatively coupled,” “coupling,” “coupled,” and variants thereof are not used lexicographically but instead are used to describe embodiments of the invention having a point, position, region, section, area, volume, or configuration at which two or more things are mechanically, chemically, and/or chemical-mechanically bonded, joined, adjoined, connected, associated, united, mated, interlocked, conjoined, fastened, held together, clamped, crimped, friction fit, pinched, press fit tight, nested, wedged, and/or otherwise associated by a joint, a junction, a juncture, a seam, a union, a socket, a melt bond, glue, adhesives, resins, welding (laser, spot, etc.), soldering, brazing, adhesives, chemical bonding materials, implanted arrangement, or combinations thereof.
Thus, the check flow body 38 provides an optional three way connector. The check flow body proximal mating end 38″ and handle coupling member 32 are operatively coupled. The side port is controlled by the detachable connector cap 39. The body distal mating end 38′ is operatively coupled to a second connector cap 39′, or optionally the handle second connector 132 is received within and operatively coupled to a handle second connector cap 130.
The foregoing description of a proximal portion 12 of a medical device delivery system 10 according to one embodiment of the invention may be one assembly during shipping, or may include a two-part assembly or more. Otherwise stated, the stylet 20 and handle 30 may be sold already combined or may be combined after purchase by inserting the stylet cannula 23 into the handle at the hospital via the threaded tapered plug 21 and threaded tapered receptacle 22. An optional safety lock 34 helps to ensure against unintentional actuation by preventing distal movement of the stylet distal end 20″ by extending inwardly within the handle chamber 30 through a slot in the handle outer wall distal to the handle proximal aperture 30′. Consequently, the optional safety lock 34 thereby maintains the handle 30 in an undeployed position until the physician is ready to deploy an implantable prosthesis (e.g., a self-expanding, balloon expandable, or non-expanding stent; prosthetic valve devices, and other implantable articles) at a selected location inside a patient's body.
Middle Section Delivery Device 14
A delivery system 10 as shown in
According to the invention, a middle section delivery device 14 is a flexible, elongate (long, at least about 50.0 centimeters (“cm”)) tubular assembly. In one embodiment, the middle section delivery device 14 is from approximately 100.0 centimeters (“cm”) to approximately 125.0 cm for use when placing a distal portion 13 of the invention within a patient's body, although it may be sized longer or shorter as needed depending on the depth of the target site within the patient's body for delivering the stent. The term “tubular” in describing this embodiment includes any tube-like, cylindrical, elongated, shaft-like, rounded, oblong, or other elongated longitudinal shaft extending between the proximal portion 12 and the distal portion 13 and defining a longitudinal axis. As used herein and throughout to describe embodiments of the invention, the term “longitudinal axis” should be considered to be an approximate lengthwise axis, which may be straight or may at times even be curved because the middle section delivery device 14, for instance, is flexible and the distal portion 13 also may be substantially or partially flexible.
A middle section delivery device 14 comprises an outer sheath 50 (e.g.,
The wall of the inner layer 44 of the outer sheath 50 has sufficient radial rigidity to decrease any tendency of bulging, kinking, and the like under an internal radial expansile force. In other words, the inner layer 44 resists an inner object from protruding or becoming embedded into the inner layer 44, which is beneficial to the slideability of an outer sheath 50. The coil 43 may be compression fitted or wound around the inner layer 44. The coil 43 includes a plurality of turns, and preferably includes uniform spacings 43′ between the turns of the coil 43. The coil 43 may be formed of any suitable material that will provide appropriate structural reinforcement, such as stainless steel flat wire or biologically compatible metals, polymers, plastics, alloys (including super-elastic alloys), or composite materials that are either biocompatible or capable of being made biocompatible.
Although the embodiment in
The outer sheath 50 for use with the middle section delivery device 14, and the outer guide channel member 80 (e.g.,
As an alternative to purchasing the outer sheath 50 for use with the middle section delivery device 14 and the outer guide channel member 80 for use with the distal portion 13 from Cook Incorporated, one may manufacture the outer sheath and outer guide channel member from various component parts. For instance, one may purchase a tubular inner layer 44 comprising a lubricious material comprising a fluorocarbon such as polytetrafluoroethylene (PTFE or Teflon) from Zeus, Inc. in Orangeburg, S.C., and dispose that inner layer 44 over a mandrel. Alternatively, a sheet of material comprising Teflon may be positioned on a mandrel and formed into a tubular body for the inner layer 44 by any suitable means known to one skilled in the art.
The tubular inner layer 44 (whether formed from a sheet on a mandrel or purchased as a tube and slid onto a mandrel) may be slightly longer than the desired length described above for the outer sheath 50 and/or outer guide channel member 80, and slightly longer than the mandrel. In one embodiment, the tubular inner layer 44 may extend about 5.0 cm from each mandrel end. As explained below, the “loose” ends of the tubular inner layer 44 help during manufacturing of the device.
The mandrel-tubular inner layer 44 assembly is prepared for a middle layer comprising a stainless steel circumferential spiral coil 43 as described above and available for purchase from Cook Incorporated or Sabin Corporation in Bloomington, Ind. As purchased, the coil 43 comes in a long, pre-coiled configuration and will be cut by hand or machine to the desired length either before or after winding the coil about the inner layer 44 to the desired length. As an alternative, one may manufacture the coil from raw material available from Fort Wayne Medical in Fort Wayne, Ind., and process it into a spiral coil 43 shape.
The operator may apply the spiral coil 43 about the mandrel-tubular inner layer 44 assembly by hand or machine. If by hand, then an end of the spiral coil 43 may be started onto the tubular inner layer 44 by any suitable means, for example, such as hooking and winding (e.g., wrapping) the coil 43 around the tubular inner layer 44 in a pigtailed manner at an initial position a desired distance (e.g., 5.0 cm or more) from a first end of the tubular inner layer 44 and to a terminating position that is a desired distance (e.g., 5.0 cm or more) from a second end of the tubular inner layer 44, and then cutting the coil 43 at the terminating position before or after hooking the coil 43 onto the inner layer 44. If by machine, then chucks, for instance, may hold the opposing ends of the mandrel-tubular inner layer 44 assembly while the spiral coil 43 is threaded through an arm on a machine and started onto the tubular inner layer 44 at the initial position as described above. As the chucks rotate, the inner layer 44 rotates, and the arm moves axially down the length of the inner layer 44, thereby applying the coil 43 in a spiral configuration about the inner layer 44. The machine arm moves to a terminating position where the machine or operator cuts the coil before or after hooking the coil 43 onto the inner layer 44.
An operator then applies an outer layer 42 about the coil-inner layer-mandrel assembly. The outer layer 42 may comprise a polyether block amide, nylon, and/or a nylon natural tubing (individually and collectively, “PEBA” and/or “nylon”). The outer layer 42 preferably has a tubular configuration that disposes about (e.g., enveloping, surrounding, wrapping around, covering, overlaying, superposed over, encasing, ensheathing, and the like) a length of the coil-inner layer-mandrel assembly.
Heat shrink tubing, available from many suppliers, including Zeus, Inc. in Orangeburg, S.C. for instance and also Cobalt Polymers in Cloverdale, Calif., may be disposed about the outer layer-coil-inner layer-mandrel assembly. Heating the assembly causes the outer layer 42 to melt. The inner surface of the outer layer 42 thereby seeps through spaces 43′ in or between middle layer coils 43 and bonds to both the outer surface of the inner layer 44 and the coils 43. In one embodiment, the inner surface of the outer layer 42 forms a melt bond 47 (explained below) to the outer surface of the inner layer 44. Upon cooling, a solid-state bond results such that the assembly comprises the three layers discussed above. The operator removes the shrink wrap (e.g., by cutting) and withdraws the mandrel. The operator may cut the Flexor® sheath to a desired length for an outer sheath 50 and/or outer guide channel member 80.
The temperature, total rise time, and dwell time for the heat shrink-outer layer-coil-inner layer-mandrel assembly will vary depending on many factors including, for instance, the actual melt bonding material that the outer layer 42 comprises, and also the diameter of the desired Flexor® sheath. For example, the baking parameters for a 2.5 French Flexor® sheath may be approximately 380 degrees Fahrenheit for about five minutes, while the baking parameters for a 4 French Flexor® sheath may be approximately 380 degrees Fahrenheit for about six minutes.
In addition to the outer sheath 50, the middle section delivery device 14 further comprises an inner compression member 41. The delivery device 14 (and, thus, the outer sheath 50 and inner compression member 41) may be constructed to have any diameter and length required to fulfill its intended purposes.
The outer sheath 50, for instance, may be available in a variety of lengths, outer diameters, and inner diameters. In one embodiment, the outer sheath 50 may have a substantially uniform outer diameter in the range from approximately 2 French to approximately 7 French, and in one embodiment the diameter is from approximately 4 French to approximately 5 French in diameter. Otherwise stated, the outer sheath 50 may range from about 0.010 inches to about 0.090 inches in diameter, and in one embodiment the diameter is approximately 0.050 inches. Likewise, the passageway 59 may be available in a variety of diameters. In one embodiment, the inner diameter ranges from about 0.032 inches to about 0.040 inches, and in a preferred embodiment the passageway 59 is approximately 0.032 inches. The diameter may be more or less than these examples, however, depending on the intended vessel passageway for the device. For instance, a larger vessel passageway (e.g., greater expandable inner diameter) may tolerate a bigger device with an outer sheath 50 having a correspondingly greater diameter. Conversely, a narrower vessel passageway may require a thinner outer sheath 50. Likewise, the overall length may vary. In one embodiment, the outer sheath 50 will have a length from about 50.0 cm (or about 19.685 inches) to about 125.0 cm (or about 49.213 inches), and more particularly between about 70.0 cm (or about 27.559 inches) and about 105.0 cm (or about 41.339 inches), and in yet another embodiment the length is approximately 100.0 cm (or about 39.370 inches).
The inner compression member 41 comprises an elongated pusher bar, stiffening member, or stiff polymer that helps to “push” the stent by pushing the stent carrying inner guide channel member at or near the distal portion 13 in order to counter the urge for the stent or stent carrying member to move as a result of an outer sheath or outer guide channel member being pulled over the stent; thereby “pushing” holds the stent in place at the desired deployment site within the patient's body. The inner compression member 41 “pushes” the stent by helping to prevent or minimize the inner guide channel member from prolapsing, recoiling, kinking, buckling, or moving; thereby keeping the inner guide channel member's stent platform on which the stent is disposed (discussed later) substantially stationary, for the most part, relative to the proximal retraction of the distal outer guide channel member (discussed below) that exposes and, thus, deploys the stent. The phrase “at or near” as used herein to describe an embodiment of the invention includes a location that is at, within, or a short distance such as about 0.1 cm to about 15.0 cm, although other ranges may apply, for instance from about 0.5 cm to about 10.0 cm.
The overall length of the inner compression member 41 may vary, as desired. In one embodiment the inner compression member 41 has a length from about 50.0 cm to about 175.0 cm, and more particularly between about 75.0 cm and 150.0 cm, and in one embodiment the length is approximately 125.0 cm to about 140.0 cm. A portion of the inner compression member 41 (e.g., the proximal end 40 and/or middle section 40′) may be contained within the handle 30 and the stylet 20, as explained above (
Likewise, the diameter or width of the inner compression member 41 may vary. In one embodiment, the inner compression member 41 has a diameter or width ranging from about 0.010 inches to about 0.030 inches, by way of example only and not by way of limitation. In one embodiment, the inner compression member 41 has a diameter or width that is approximately 0.016 inches. The diameter or width may be more or less than these illustrative ranges. For example, a deeper target site within a patient may require a thicker inner compression member 41 for greater push-ability, but may tolerate lesser flexibility. In addition, the material that the inner compression member 41 comprises determines whether a smaller and more flexible inner compression member 41 will give suitable flexibility, and also determines whether a wider inner compression member 41 may have the flexibility of a thinner inner compression member 41 made of different material. Furthermore, the inner compression member 41 may have a curved transverse cross-section, such as, for example, a circular cross-section, or it may have a polygonal cross-section, such as, for example, a rectangular cross-section. Alternatively, the transverse cross-section of the inner compression member may include both curved and straight portions. According to one embodiment, the inner compression member 41 may have a nonuniform diameter or width along its length. These various diameters, widths, and cross-sections may occur at the inner compression member proximal end 40, the inner compression member middle section 40′, and/or the inner compression member distal mating end portion 48. It should be understood that the diameter, width, and/or cross-section of the inner compression member 41 may taper.
Also, an inner compression member 41 may have an outer surface comprising a lubricious PTFE material and/or an inner surface 44 of the outer sheath 50 may comprise a lubricious PTFE material against the inner compression member 41, in order to allow easy retraction of the outer sheath 50, which is in communication with a distal outer guide channel member to deploy a self-expanding stent, as will be explained later.
Generally, the inner compression member 41 and outer sheath 50 may optionally be approximately the same in length, and the axial length of coil 43 will be less than the length of the inner compression member and outer sheath. In one embodiment, however, the inner compression member 41 comprises a proximal end 40 that extends proximal relative to the outer sheath. In yet another embodiment, the inner compression member extends to a position that is distal the outer sheath. In still another embodiment, the inner compression member 41 stops short of extending all the way to the distal tip of the delivery system 10, and may stop generally from 10 to 40 cm short of the distal tip of the delivery system 10, and in one embodiment it stops approximately 20 to 25 cm short of the distal tip of the delivery system 10, where the distal end portion of the inner compression member 41 is operatively coupled to a proximal portion of an inner guide channel member.
As an alternative to a Flexor® sheath discussed above, the outer sheath 50 may have a construction comprising multifilar material, round wire, cable tubing, spiral cut cannula, cable tubing connected to spiral cut cannula, round wire braid, flat braid, and any equivalents thereto and/or combinations thereof.
In particular,
The middle section delivery device 14 of
According to the embodiments of the outer sheath 50 shown in
Operatively Coupling the Middle Section Delivery Device 14 and the Distal Portion 13
Against the foregoing description of embodiments of the proximal portion 12 and middle section delivery device 14 and before discussing embodiments of the distal portion 13 of the delivery system, the invention further comprises associating the distal portion 13 and the middle section delivery device 14. These ways of operatively coupling the middle section delivery device 14 and distal portion 13 allow the outer guide channel member 80 of the distal portion 13 to move relative to the inner guide channel member 70 of the distal portion 13. In particular, the outer sheath 50 of the middle section delivery device 14 may be operatively coupled with the outer guide channel member 80 of the distal portion 13. Also, the inner compression member 41 of the middle section delivery device 14 may be operatively coupled with the inner guide channel member 70 of the distal portion 13. Therefore, the ways of constructing or joining the middle section delivery device 14 and distal portion 13 as described below are merely illustrations of non-limiting embodiments only.
In one embodiment, outer guide channel member 80 of the distal portion 13 and the outer sheath 50 of the middle section delivery device 14 may be constructed as comprising an integral unit. In other words, the same outer body sheath 50 construction shown and described in connection with
Moreover, where coil, multifilar material, weave, or braid (as described in the context of
Another embodiment may be used for constructing or joining the middle section delivery device 14 and distal portion 13 in a way that permits the outer guide channel member 80 of the distal portion 13 to move relative to the inner guide channel member 70 of the distal portion 13. In this embodiment, the outer sheath 50 of the middle section delivery device 14 and the outer guide channel member 80 of the distal portion 13 comprise a plurality of units. Each unit may comprise the construction shown and described above in connection with the discussion relating to
In one assembly, the distal portion 13 and the middle section delivery device 14 may be put together by any suitable connector. By way of example, the middle section delivery device 14 and distal portion 13 may be put together with a lap joint or a brace.
According to
Also, the puller 54 may join a plurality of coils, multifilar materials, weaves, or braids end-to-end. Furthermore, the puller 54 may join a plurality of segments comprising a coil, multifilar material, weave, or braid. Moreover, the puller 54, when used with a “Flexor®” sheath as an outer sheath 50 of a middle section delivery device 14 as previously described, provides additional strength anywhere support is needed to provide structural integrity, such as when there is a gap between the bridged components, or a reduced cross sectional area of a component compromises that component's structural integrity.
In one embodiment, the puller 54 is generally rectangular, polygonal, or irregular in shape or cross section and is positioned approximately parallel to a longitudinal axis 246 of the brace section 240. Alternatively, the distal portion 13 and the middle section delivery device 14 may be attached, adjoined, joined, or combined by a brace section 240, wherein the puller 54 is a mechanical connector selected from the group consisting of a wire, inward protrusion, nuts and bolts, pins, clamp, pincher, hook, fastener, joint, ring, sheath, ball and socket, full or partial bearing, shaft, thread, cable, rod, bar, ball or hemispherical ball, fulcrum, support, linkage, or other crimping, clutching, gripping, joining, or holding mechanical holding materials, to name a few illustrative examples of mechanical connectors for operatively coupling the middle section delivery device 14 and the distal portion 13 in accordance with an embodiment of the invention. Other examples of a puller 54 include glue, adhesives, resins, welding, soldering, brazing, adhesives, or chemical bonding materials or combinations thereof. By way of further illustration, the distal portion 13 and middle section delivery device 14 may be attached by a puller 54 that is a stainless steel coil.
A bridging device 100 has a low profile and may vary in length, thickness, and width. For example, the length may be from 1 cm to about 10 cm or more, and in one embodiment from about 2 cm to about 6 cm, or it may correspond to the approximate length of the self-expanding device in a compressed state or the approximate length that the outer guide channel member may need to slide relative to the inner guide channel member to deploy the self-expanding device. Moreover, the low profile of the bridging device 100—relative to the distal portion 13 or middle section delivery device 14—facilitates the exiting of a wire guide from a breech position opening 65 located at or near the rear, back, or proximal part of the distal portion 13. The low profile and length allow the physician to grab the exiting wire guide as needed. The physician may desire to feed the exiting wire guide into another instrument, into a passageway of the middle section, or through one or more eyelets attached to maintain the wire guide the middle section to substantially parallel with or side-by-side with the middle section delivery device 14.
The bridging device 100 further comprises a link member 101′ joining the bridge to the distal portion 13 and a link member 101 joining the bridge to the middle section delivery device 14. The link members 101, 101′ may be any puller 54 described above for assembling the middle section delivery device 14 and distal portion 13, where the puller 54 is a connector selected from the group consisting of mechanical structures, chemical bonding materials (resins, glue, adhesives, and the like), and welding (soldering, brazing, and the like) materials or combinations. Certain additional non-limiting examples of link members 101, 101′ comprise a nut, bolt, screw, thread, suture, cotter and pin, spring, full or partial bearing, bearing surface, rivet, pin, shaft, thread, joint, or other linkage or securing mechanism. Furthermore, a link member 101, 101′ may join the bridging device 100 to an outer surface or an inside surface of the middle section delivery device 14 or distal portion 13.
The bridging device 100 may comprise a single span construction or a plurality of spans.
The bridging device 100 may be made of any suitable material used for the middle section delivery device 14 as described above or used for the distal portion 13 as described below. The material is resilient with sufficient column strength to be kink resistant. Optionally, the bridging device 100 may be pliable, elastic, twistable, and flexible. For illustration, only
Optionally, the span 102, first span 104, and second span 106 may articulate about link members 101, 101′ as shown in
Articulation, as used here, means that one or more of the following pieces is moveable relative to one or more of the other pieces: middle section delivery device 14, spans (102, 104, 106), and distal portion 13. Articulation may include one or more degrees of translational displacements and/or rotations. For instance, the articulation may be axial, longitudinal, forward, backward, orthogonal, lateral, transverse, rotational, pivotable, sloping incline or decline, swinging, torsional, revolving, and other forms of translation and/or rotation in an x, y, and/or z coordinate system.
According to
The lengths of the inserts 220, 230 may vary from about 10 to 40 mm. In an alternative embodiment, the lengths are approximately 15 to 25 mm. In still another embodiment, the lengths are approximately 20 mm. The diameters of the guide channel 281, 231 also may vary. In most cases, the diameter will range from approximately 2 to 7 French, with a preferred embodiment from approximately 4 to 5 French in diameter. The openings 283′, 233 may be at an angle between a range of zero to about 90 degrees relative to an axis of the insert 220, 230, respectively.
A distal insert 220 has an outer member mating portion 222 secured to an outer guide channel member 80, while a proximal insert 230 has an outer sheath mating portion 232 bonded to the outer sheath distal end 58. In one embodiment, the outer member mating portion 222 of the distal insert may be secured to an inner layer 44 within the outer member guide channel 81, while the outer sheath mating portion 232 of the proximal insert 230 may be secured to an inner layer 44 within the outer sheath passageway 59. In an alternative embodiment, the mating portions 222, 232 of the distal insert 220 and proximal insert 230 may be received by and secure to the outer layer 42 of the outer guide channel member 80 and the outer sheath 50, respectively.
As shown in
Optionally, the inner compression member distal mating end 48 may be secured to a proximal insert 230 and an inner guide channel member second end portion 77 may be secured to a distal insert 220. The insert interfacing ends 224, 234 are brought together and operatively coupled by any suitable connection discussed above. Alternatively, the proximal insert 230 may be omitted, and the distal insert interfacing end 224 may be operatively coupled directly to the inner compression member distal mating end 48 by glue, adhesive, resin, welding, fusing, soldering, brazing, melt bonding, crimping, or other mechanical or chemical bonding materials or combinations thereof.
System Distal Portion 13
Now turning to embodiments of a distal portion 13 of medical device delivery systems according to the invention,
The distal end 13, according to the delivery system 10 and shown in
The inner and outer guide channel members 70, 80, respectively, may be made of any suitable material described above for use with the distal end 13. In one embodiment, the inner guide channel member 70 and the outer guide channel member 80 comprise PEEK material, which has the advantage of softening under heat before burning or degrading. PEEK tubing may be purchased from many suppliers, such as Zeus, Inc. in Orangeburg, S.C. for instance.
Beginning with the inner guide channel member 70, a description will follow relating to features common to embodiments of a distal end 13 of a delivery system 10 for the rapid insertion of “stents” according to the invention. The inner guide channel member 70 is generally tubular and comprises a first end portion 78 and a second end portion 77 defining a wire guide channel 71 therebetween. Optionally, the inner guide channel member 70 is configured to be slidably nested, fitted, secured, or otherwise positioned within the outer guide channel member 80 such that at least one of the inner guide channel member first or second end portions 78, 77, respectively, is axially intermediate an outer guide channel member first end portion 88 and an outer guide channel member second end portion 87.
The first end portion 78 of the inner guide channel member 70 further comprises a wire guide entry port 72, and the second end portion 77 has a wire guide exit port 73. The entry and exit ports 72, 73, respectively, define and are in communication via the wire guide channel 71. A port, in describing an embodiment of an inner guide channel member 70 and an outer guide channel member 80 according to the invention, includes any structure that functions as an entry or exit aperture, cutout, gap, hole, opening, orifice, passage, passageway, port, or portal. The inner guide channel member entry port 72 is sized to receive a wire guide into the inner member guide channel 71, and the inner guide channel member 70 is configured so that the wire guide may exit proximally out the inner guide channel member exit port 73. Optionally, the exit port 73 is located at or near the transition region 60. In one embodiment of the present invention, the inner guide channel member 70 is a cannula (or catheter) having an entry port 72 and an exit port 73 as previously described and defining a guide channel 71 therebetween.
The inner guide channel member 70 further comprises an outer self-expanding deployment device mounting region 90 (e.g., an outer stent mounting region) positioned intermediate the inner guide channel member entry and exit ports 72, 73, respectively. The length of the inner guide channel member 70 of any of the embodiments of the present invention may vary generally from about 10.0 to about 40.0 cm. In one alternative embodiment, the length of the inner guide channel member 70 is approximately 15.0 to approximately 25.0 cm. In another embodiment, the length of the inner guide channel member 70 is approximately 20.0 cm. Also, the length of the inner guide channel member 70 may depend on the intended stent, and in another embodiment the length of the inner guide channel member 70 is approximately 15.0 cm for an 8.0 cm stent.
The inner guide channel member 70 further comprises inner and outer diameters. In one embodiment, both diameters are substantially uniform over the entire length of the inner guide channel member 70. By way of example, an internal diameter 74 might measure approximately 0.0205 inches at or near the inner guide channel member proximal second end portion 77, at or near the inner guide channel member distal first end portion 78, and intermediate the first and second end portions 78, 77, respectively. Likewise, an inner guide channel member 70 might have an outer diameter 75 that measures approximately 0.0430 inches. Thus, the outer diameter 75 might measure approximately 0.0430 inches at or near the inner guide channel member proximal second end portion 77, at or near the inner guide channel member distal first end portion 78, and intermediate the first and second end portions 78, 77.
In an alternative embodiment to an inner guide channel member 70 having a substantially uniform outer diameter 75 along its length from about the second end portion 77 to about the first end portion 78, the inner guide channel member may also comprise a tapered outer diameter 76. In one embodiment, the inner guide channel member tapers distally to a second outer diameter 76′ at or near the inner guide channel member first end portion 78 or intermediate the inner guide channel member first and second end portions 78, 77, respectively. The taper 76 has a decreased cross section, diameter, width, height, area, volume, thickness, and/or other configuration, shape, form, profile, structure, external outline, and/or contour relative to the outer diameter 75. In other words, the inner guide channel member second outer diameter 76′ is smaller in cross section, diameter, width, height, area, volume, thickness, and/or other configuration, shape, form, profile, structure, external outline, and/or contour than the outer diameter 75.
The atraumatic tip second end portion 177, as shown in
In
In one embodiment, the Flexor® sheath, manufactured and sold by Cook Incorporated of Bloomington, Ind., may be adapted for use with the distal end 13 and/or the middle section delivery device 14. Otherwise stated, the Flexor® sheath, as shown in
The Flexor® sheath has a PTFE inner lining 44 that provides a slick, smooth surface for sliding the outer sheath 50 and/or the outer guide channel member 80 proximally. With regard to the distal end 13, the outer guide channel member 80 slides relative to the inner guide channel member 70, and a stent constraining inner surface 92 of the outer guide channel member 80 would be the inner layer 44 described above, thereby resulting in minimal friction to a stent 17 on the stent platform 91. The slidable inner surface 92 of the Flexor® sheath exhibits a second benefit of minimizing damage or misalignment to the stent. Indeed, because self-expanding stents continuously exert an expanding force against the inside surface 92 of the outer guide channel member 80, any substantial friction or drag between the stent and the inner surface 92 of the outer guide channel member 80 as the outer guide channel member 80 withdraws may damage the stent or cause the stent to be deployed slightly off of the target site.
The thin flat wire reinforcing coil 43 of the Flexor® sheath provides the outer guide channel member 80 with the necessary radial strength to constrain the stent over long periods of storage time. In contrast, where the a stent constraining inner surface 92 of an outer guide channel member 80 does not comprise the Flexor® sheath inner layer 44 or equivalent, the stent over time may tend to become imbedded in the inner surface 92 and, as a result, interfere with retraction of the outer guide channel member 80 at the time of deployment. In an outer guide channel member 80 that comprises a Flexor® sheath, in addition to the inner layer 44 and the reinforcing coil 43, the outer guide channel member 80 has a Flexor® sheath outer layer 42. The outer layer 42 comprises nylon and/or PEBA to provide the necessary stiffness for pushability, retraction, and control of the outer guide channel member 80 to facilitate proper deployment of the constrained self-expanding stent. Therefore, the Flexor® sheath is one non-limiting example of an embodiment of an outer sheath 50 and/or an outer guide channel member 80.
While
Furthermore, the outer guide channel member 80 has a stepped 84, 85 profile, whereby the outer guide channel member 80 comprises a first outer diameter 84 intermediate the outer guide channel member first and second end portions 88, 87, respectively, and a second smaller outer diameter 85 located at or near the outer guide channel member second end portion 87 in the vicinity of the transition region 60 and the breech position opening 65. The stepped 84, 85 profile includes an embodiment where the outer guide channel member 80 transitions to the distal end portion 58 of the outer sheath 50 of the middle section delivery device 14. In describing embodiments of the invention, however, the stepped 84, 85 profile shall be discussed in reference to the outer guide channel member 80 in particular, but it should be understood as including a stepped 84, 85 profile in reference to the transition region 60 of the distal end 13 relative to the middle section delivery device 14 where the middle section delivery device 14 and distal end 13 are formed from separate units such as, by way of example only and not by way of limitation, separate “Flexor®” sheaths where one comprises a first outer diameter 84 and the other comprises a second smaller outer diameter 85.
As shown in
In one embodiment of the stepped 84, 85 profile of the outer guide channel member 80, the second smaller outer diameter 85 is located at or near the outer guide channel member second end portion 87. The second end portion 87 may decrease precipitously from the first outer diameter 84 to the second smaller diameter 85. In a precipitous step, the change from the diameters occurs over a short length along the longitudinal axis of the distal end 13. In a further example of a precipitous step, the plane formed by the exit port 83 may be substantially perpendicular to the longitudinal axis of the outer guide channel member 80. In an alternative embodiment, the second end portion 87 may decrease gradually from the first outer diameter 84 to the second smaller diameter 85. In a gradual step, the change from the two diameters occurs over a length of more than 1.0 millimeter (“mm”) along the longitudinal axis of the distal end 13 at or near the transition region 60 and breech position opening 65, and in one instance this change occurs over a length from about 1.0 mm to about 10.0 mm. In a further example of a gradual step, the plane formed by the exit port 83 may be at an angle other than 90 degrees relative to the longitudinal axis of the distal end 13.
The breech position opening 65 may be used for front-loading and the more common procedure of back-loading a wire guide (or catheter, for instance). In a back-loading procedure for a delivery system having a breech position opening 65, the wire guide may pass proximally through the guide channel 71 of the inner guide channel member 70, proximally through the guide channel 81 of the outer guide channel member 80, and leave the exit port 83 of the second end portion 87 of the outer guide channel member 80 from a breech position opening 65 in a rear, back, or proximal part of the distal end 13. Conversely, in a front-loading procedure for a delivery system having a breech position opening 65, the physician may feed the wire guide distally into a breech position opening 65 at the rear, back, or proximal part of the distal end 13 by entering the exit port 83 of the second end portion 87 and the guide channel 81 of the outer guide channel member 80 and through the guide channel 71 of the inner guide channel member 70, where the wire guide may exit from the wire guide entry port 72 of the inner guide channel member 70 and/or wire guide entry port 172 of the atraumatic tip 170.
In a distal portion 13 having a breech position opening 65 that comprises an exit port 83 located at a breech position of the transition region 60 according to the invention, the wire guide does not need to make any sharp turns away from the longitudinal axis of the guide channel 71 of the inner guide channel member 70 and/or the distal portion 13 generally that may result in kinking of the wire guide. In one embodiment, the exit port 83 is spaced proximally of the inner guide channel member second end portion 77 and is substantially (e.g., less than 30 degrees and preferably less than 15 degrees) along the longitudinal axis of the inner guide channel member 70 such that the longitudinal axis of the inner guide channel member 70 intersects the exit port 83, runs through the exit port 83, or the exit port 83 otherwise lies along the plane of the longitudinal axis of the inner guide channel member 70. In another embodiment, the exit port 83 is within the plan form by the side walls of the outer guide channel member 80, as opposed to a sideport that is within the sidewall of the outer guide channel member 80, wherein the wire guide needs to may a sharp turn away from the longitudinal axis of the guide channel 71. In another embodiment, the breech position opening 65 comprises an exit port 83 according to embodiments of the invention, as those shown in
In
The overall axial length of the exit port 83 of the breech position opening 65 may vary. In one embodiment, the length is approximately from about 1.0 mm to about 10.0 mm. Another embodiment has a length of approximately 5.0 mm. The overall width of the exit port 83 may also vary. In one example, the width of the exit port is approximately 1 French. In yet another instance, the width of the exit port 83 ranges from about 1 French to about 4 French. In another example, the width of the exit port 83 may be the approximate difference between the first outer diameter 84 and the second outer diameter 85 of the outer guide channel member 80. In yet another embodiment, the exit port 83 comprises a diameter defined as being substantially equal to the difference between the outer guide channel member first outer diameter 84 and the outer guide channel member second smaller outer diameter 85.
At the transition region 60, the exit port 73 of the inner guide channel member 70 is in communication with the outer guide channel member 80 wire guide entry port 82, while the second end portion 77 is operatively coupled to the distal mating end 48 of the inner guide channel member 70 as explained below. The length of the transition region 60 may vary. For instance, the transition region 60 may be approximately from about 0.5 cm to about 10.0 cm. In another embodiment, the transition region 60 has the approximate length of about 5.0 cm. Furthermore, the length of the transition region 60 is variable: from a shorter axial length when the outer guide channel member 80 is in a non-deployed axial position; to a greater axial length when the outer guide channel member 80 retracts proximally to deploy the stent. Likewise, the overall length of the transition region 60 varies in the embodiment where the exit port 83 is distal to the entry port 82 when the outer guide channel member 80 is in a non-deployed stent position, compared to the initial length of the transition region 60 in an embodiment where the exit port 83 is proximal to the entry port 82 when the outer guide channel member 80 is in a non-deployed stent position.
In one use of the transition region 60 according to an embodiment of the invention, the outer guide channel member entry port 82 receives a wire guide from the inner guide channel member exit port 73 and the wire guide thereby is received in the outer member guide channel 81. At the transition region 60, the inner member guide channel 71 and outer member guide channel 81 are approximately aligned relatively coaxially in one embodiment. Approximate alignment of the guide channels 71, 81 facilitates a smooth transition of the wire guide. Smooth transition optimally reduces any bending of the wire guide as the wire guide moves proximally from the inner member guide channel 71 to the outer member guide channel 81.
Several factors individually or collectively may further ensure that the inner member guide channel 71 and outer member guide channel 81 are approximately aligned relatively coaxially so that the wire guide may find its way out the distal portion 13. The breech position opening 65 is located in a longitudinally optimal location at the rear, back rear, back, or proximal part of the distal portion 13. Also, the breech position opening 65 is large enough to provide an easy exit; if too large it compromises the structural integrity of the outer guide channel member 80 and/or the transition region 60, and a puller 54 as taught herein may be needed. Furthermore, the inside shape of the breech position opening 65 is conducive to receiving the wire guide and directing it out, as with the [lateral walls 83a, 83b that act as guide rails to direct a wire guide proximally toward the middle section delivery device 14 and to run along the outside of the outer sheath 50, and/or with the overall axial length of the exit port 83 of the breech position opening 65 from about 1.0 mm to about 10.0 mm and alternatively approximately 5.0 mm, and/or the overall width of the exit port 83 of approximately from about 1 French to about 4 French or the difference in the first outer diameter 84 and the second outer diameter 85. Furthermore, outer sheath 50 has a passageway that is only large enough for the inner compression member 41 to pass through but not large enough to provide a receptacle for the wire guide as it is being fed through the distal portion 13.
Moreover, as the delivery system is being assembled, a pseudo-wire guide may be threaded through the breech position opening “backward” from normal. The pseudo-wire guide is then threaded backward through the inner guide channel member 70. As the outer guide channel member 80 and inner guide channel member 70 are slid together longitudinally, the pseudo-wire guide ensures that the inner guide channel member exit port 73 and the outer guide channel member exit port 83 are rotationally aligned. Because the outer guide channel member 80 is operatively coupled to the outer sheath 50 and the inner guide channel member 70 is operatively to the inner compression member 41, by connected the outer sheath proximal end 57 and the inner compression member proximal end 40 at the system proximal portion 12 as described above, this locks the inner guide channel member exit port 73 and the outer guide channel member exit port 83 into a properly aligned relationship. Then, the pseudo-wire guide can be removed, or left to function as a shipping fixture that is removed by the end user.
As shown in
The stent mounting region 90 comprises a stent platform 91 on an outside surface of the inner guide channel member 70 located at or near the inner guide channel member second end portion 78. In describing embodiments of the invention, the platform 91 “at or near” the inner guide channel member second end portion 78 includes a region intermediate the inner guide channel member entry port 72 and the inner guide channel member exit port 73. The platform 91 may be any stent mounting surface, including but not limited to the outside surface of the inner guide channel member 70, a recess, or an indentation located at or near the first end portion 78 of the inner guide channel member 70. In a non-deployed state, a self-expanding stent for example (not shown) compresses against the stent platform 91 and disposes around the outside of the inner guide channel member 70.
The stent mounting region 90 controls the lateral movement (e.g., transverse expansion away from the inner guide channel member longitudinal axis) to avoid premature deployment of the stent. In order to control the lateral movement of the stent, the stent is sandwiched between the platform 91 on the inner surface of the stent and the stent constraining inner surface 92 of the outer guide channel member 80 to keep the stent in a compressed state. Because the stent is bound from above by the inner surface 92 of the outer guide channel member 80 and bound from below by the platform 91 of the inner guide channel member 70, the stent mounting region 90 maintains the stent in a substantially compressed state and controls premature deployment of the stent.
In addition to controlling a stent's lateral movement, the stent mounting region 90 restrains the axial movement of a stent to control the stent movement away from the target site. A proximal restraint 93 controls proximal axial movement of the stent. In one embodiment, the proximal restraint 93 is sized to be large enough to make sufficient contact with the loaded proximal end of the stent without making frictional contact with the inner surface 92 of the outer guide channel member 80. In addition to helping to stop the stent's proximal movement in the non-deployed state, this restraint 93 assists with “pushing” the stent out of the distal end 13 by helping to prevent the inner guide channel member 70 and/or the stent disposed on the stent mounting region 90 from migrating proximally when the outer guide channel member 80 retracts proximally relative to the stationary inner guide channel member 70 in order to expose and deploy the stent. Optionally, the restraint 93 may be radiopaque so as to aid in stent positioning within the vessel passageway at or near the target site within a patient. In one embodiment, an optional distal restraint 93′ is large enough to make sufficient contact with the loaded distal end of the stent to control axially distal movement of the stent. Similarly, in another embodiment the proximal second end portion 177 of an optional atraumatic tip 170 controls the stent's distal axial movement. Indeed, because the medical device delivery system may be used for deploying an implantable prosthesis that comprises balloon expandable or non-expanding stents, prosthetic valve devices, and other implantable articles at a selected location inside a patient's body, the proximal restraint 93 and distal restraint 93′ control the axial distal movement of the implantable prosthesis. Optionally, the distal restraint 93′ and/or atraumatic tip 170 may comprise radiopaque materials so as to aid in stent positioning within the vessel passageway at or near the target site within a patient.
In one embodiment, the inner compression member outer engaging surface 48′ may form a melt bond 47 to an inner surface 101 of the inner guide channel member second end portion 77. Alternatively, the inner compression member outer engaging surface 48′ may form a melt bond 47 to the outer surface 102 of the inner guide channel second end portion 77. In yet another embodiment, the distal mating end 48 of a solid inner compression member 41 as shown in
As used to describe an embodiment of the invention, melt bonding 47 (for shorthand purposes in describing embodiments according to the invention, melt bonding 47 includes implanting 49) comprises any suitable means for melting, liquefying, making semi-molten, making molten, softening, making tacky, fusing, or making malleable, pliant, supple, moldable, ductile, or otherwise penetrable by another component or fused to melt bonding material comprising the other element. For instance, melt bonding 47 involves bringing two components together at an interface, wherein one (or preferably both) of the component interfaces are in the melted state. Strictly speaking, true melt bonding 47 requires that both of the components be melted at the interface and that they may be sufficiently chemically and physically compatible such that they fuse together upon cooling.
The melt bonding materials comprising the two components may be the same or substantially same materials. In the alternative, the melt bonding materials may be different, so long as they have substantially similar melting points at standard atmospheric pressure such that the materials soften (or liquefy) under heat and thereby fuse together in a solid state melt bond 47 joining the first and second melt bonding materials of the components. If the materials had melting points that were too different, then one material may degrade or burn and the like before the second material begins to melt.
Melt bonding 47 may be single layer interface whereby one component interface/surface mates to a second component interface/surface, or may be multi-layer interface whereby one component is implanted 49 into a second component and then surrounded by the second component. The chemical compatibility can best be expressed in terms of having similar values for surface energy and/or solubility parameter. In simple terms, similar materials tend to have a mutual affinity and a greater propensity to adhere to one another than do dissimilar materials. Melt bonding includes bonding whereby one component is melted while the other component is at or above its melting point.
Melt bonding materials may have different “melt bonding” temperatures at which they soften and become almost tacky without substantial degradation. Melt bonding materials are available from vendors, including Zeus, Inc. in Orangeburg, S.C. for instance; Cobalt Polymers in Cloverdale, Calif.; and under the trade name of Pebax® PEBA from the Arkema Group. The melt bonding materials may include one or a combination of a class of suitable materials comprising nylon, nylon natural tubing, polyether block amide, polyetheretherketone, thermoplastic, acrylonitrile-butadiene-styrene copolymer, polypropylene, polyamide, ionomer, polycarbonate, polyphenylene oxide, polyphenylene sulphide, acrylic, liquid crystal polymer, polyolefin, polyethylene acrylate acid, polyvinylidene fluoride, polyvinyl, and polyvinyl chloride.
In one embodiment, PEEK material is used for the melt bonding material. PEEK melts at about 633° F., so the material may be heated from about 628° F. to about 638° F. For instance, a radiofrequency loop heater may be used for heating the melt bonding materials. Such a machine is available from Magnaforce, Incorporated and sold under the name and model Heatstation 1500. Another such machine is available from Cath-Tip, Inc. and is sold under the model and name Cath-Tip II. There is a rise dwell and cool down time for the process. The total rise time is approximately 20 seconds and dwell time is approximately 10 seconds. During the dwell time the temperature is approximately 600° F. In one embodiment where nylon or PEBA are used, heating is at about 400° F., with dwell time of about 10 seconds.
In the example represented in
The tubular inner compression member 41 may have a uniform inside diameter ranging from about 0.0527 to about 0.132 inches. The wall thickness of the tubular inner compression member 41 is approximately 0.0015 inch. These dimensions are illustrative only, and the inner diameter and wall thickness may be constructed to be of any size necessary to accomplish the purposes for which the delivery system is to be employed (i.e., limited by the vessel passageway or working channel in which the device is to be used).
In addition, this inner compression member 41 has an optional distal one-way valve 61. Thus, the valve 61 may serve a dual function. First, a one-way valve is relatively resistant to contamination from bodily fluids entering the inner compression member passageway 45. Second, it allows the movement of medication and/or fluids to exit distally the inner compression member 41 passageway 45 at or near the transition region 60 and may direct medication and/or fluids into the inner member guide channel 71 and/or the outer member guide channel 81.
Indeed, the inner compression member passageway 45 may facilitate using the medical device delivery system for deploying an implantable prosthesis that comprise balloon expandable stents, prosthetic valve devices, and other implantable articles (individually and collectively, “stent”) at a selected location inside a patient's body. The stent is disposed at the deployment device mounting region 90 intermediate the proximal restraint 93 and distal restraint 93′ to control the axial distal movement of the implantable prosthesis.
In one embodiment for using the delivery system with a balloon expandable implantable prosthesis, the inner compression member distal mating end portion engaging surface 48′ operatively couples to the inner guide channel member outer surface 102 (or is welded to an outer surface of a metal cannula that has the inner guide channel member second end portion 77 glued within the cannula lumen), and an inflation member (e.g., a balloon) extends distally from the inner compression member distal mating end portion and is disposed over the proximal restraint 93 and distally about the platform 91 of the stent mounting region 90 such that the balloon is located under the stent. The stent is positioned within the vessel passageway at or near the target site within a patient, wherein the outer sheath 50 and outer guide channel member 80 is axially slideable relative to the inner compression member 41 and inner guide channel member 70 upon corresponding axial slideable movement of the handle 30, thereby exposing and, ultimately, deploying the stent from the stent mounting region 90. The stylet 20 may be adapted to receive a syringe for allowing inflation fluid, such as saline, to travel from and through the proximal end 40 of the inner compression member 41 and out the valve 61 at the distal end portion 48 in order to fill the inflation chamber of the balloon. Therefore, balloon expands under the stent and, as a result, the stent expands radially to plastically deform the stent into a substantially permanent expanded condition. The physician then deflates the balloon and removes the inner guide channel member 70 and remainder of the delivery system from the patient's body. This description of using the delivery system for balloon expandable implantable prosthesis is given by way of example and not by way of limitation. Alternatively, a tubular inflation fluid carrying device is in the outer sheath passageway 59 and extends from the system proximal portion 12 to the system distal portion 13 and operatively couples to an inflation member disposed under the stent.
In one embodiment of the distal portion 13 of a delivery system illustrated in
The embodiment shown in
Moving to the atraumatic tip 170 as illustrated in
Turning now to
In
In one embodiment, the cannula 95 is a hollow, rigid tube, cylinder, ring, cannula (with or without a trocar), or other coupling device comprising metal such as medical grade stainless steel or super-elastic alloys (e.g., nitinol) to name but a few non-limiting examples. In one embodiment, the cannula 95 comprises a generally right cylindrical configuration or is elliptical, hyperbolic, parabolic, curved, polygonal, rectangular, or irregular in shape or cross section. The cannula 95 is sized for receiving the inner guide channel second end portion 77 and/or the inner guide channel second end portion outer diameter 75. The outer surface 102 of the inner guide channel second end portion 77 is operatively coupled to an inner engaging surface of the securing body 95 by glue, adhesives, resins, chemical bonding materials or combinations thereof and the like (collectively and individually, “glue”). By way of example only, the glue may be Loctite 4061 instant adhesive, formulated to polymerise rapidly in thin films between two surfaces to form rigid thermoplastics. Loctite 4061 instant adhesive is a medical device adhesive particularly suitable for a wide variety of substrates such as rubber, plastics, and metals, ant it is available from the Loctite Corporation.
In addition to securing the outer surface 102 of the inner guide channel member second end portion 77 to an inner engaging surface of the cannula 95, the cannula 95 also operatively couples the inner guide channel member distal mating end portion 48. An outer engaging surface 48′ of the mating end portion 48 is in an abutting relationship (e.g., touching, in contact directly or by intervening parts, or adjacent) to an outer engaging surface of the cannula 95, and the mating end portion 48 and cannula 95 are operatively coupled by any suitable means, including but not limiting to welding, soldering, brazing, or fusing. Soldering and brazing are used if a semi-permanent connection between the distal mating end portion 48 and the cannula 95 is desired, because solder or braze metals have a lower melting point than the metals that are joined. Thus, when sufficient heat is applied to melt the solder or braze metal, they form an alloy with the surfaces of the mating end portion 48 and the cannula 95 and, upon solidification, thus form a joint that can be unfastened during manufacturing (e.g., to redo in the event of a poor connection) by reheating without destroying the parts that have been joined. In contrast, welding involves melting the outer engaging surface 48′ of the mating end portion 48 and an outer engaging surface of the cannula 95 at the interface, or involves combining temperature and pressure so as to cause localized coalescence. Consequently, in most instances higher temperatures are involved than for soldering, and the union is permanent.
Where the inner compression member distal mating end portion 48 and the cannula 95 are connected, an optional tube may be disposed about the joint 46. The tubing has the advantage of minimizing some of the sharp edges created by a welded, soldered, or fused joint. In one embodiment, the tube is a melt bonding tube disposed about and melt bonded to the joint 46. Whereas
According to
In addition, the contoured configuration 48″ maintains low profile, high-strength, and flexibility of the connection between the inner compression member distal mating end portion 48 and the cannula 95. The contoured configuration 48″ is in contrast to a rounded inner compression member distal mating end portion 48, which would have a greater diameter at the connection between the inner compression member distal mating end portion 48 and the cannula 95.
In order to create the contoured configuration 48″, the inner compression member distal mating end portion 48 may be formed, sheared, casted, or molded. By way of example only, forming can be done both hot and cold (except for stamping, which is always done cold) in order to modify the shape and/or physical properties of the material comprising the inner compression member distal mating end portion 48. Common forming processes include rolling the distal mating end portion 48 (between one or two rollers), stretching, forging, straight bending, and stamping.
By way of illustration and not by way of limitation,
More specifically,
Likewise, the guide channel 71 of the inner guide channel member 70 and the guide channel 81 of the outer guide channel member 80 may assume numerous configurations to ensure a low profile at the distal end, and to guide the wire guide 16. These configurations include but are not limited to spherical, elliptical, crescent, saddle, slit, or wishbone shapes, such as by way of illustration the co-axial channels 71, 81 of
The puller 54 of the embodiment of the distal portion 13 of
The puller 54 may vary in length and height. The length may vary from about 1 to 10 cm, from about 2 to 6 cm, and in one embodiment has a length of approximately 5 cm. Optionally, the puller could run approximately the length of the middle section delivery device 14, or about 125 cm, so long as the puller height increases at or near the proximal wire guide exit port 83 of the outer guide channel member 80 to lift the inner compression member 41 and occlude the wire guide 16. The overall height, as measured from a longitudinal axis of the distal portion 13 at or near the exit port 83, also may vary. In one embodiment, the height approximately equals or slightly exceeds the absolute difference between the outer diameter 84 and the inner diameter 85. In another embodiment, the height is from about 0.2 French to about 2.0 French, and in another the height approximates 1 French.
As a stiffening element, the puller 54 reduces the flexing, buckling, kinking, or bending of the distal end at or near the exit port 83. Moreover, the puller 54 may be used where structural integrity is compromised, as in a case where the exit port 83 is a large longitudinal gap and reduced material, low profile, and circumference at the breech position opening 65 as shown in
As an optional occlusion element, the puller 54 may lift the inner compression member or the wire guide 16 in order to ensure that the wire guide 16 does not enter a passageway 45 (e.g.,
In this embodiment, the distal portion 13 of the device comprises a venting structure. A flushing port 94 is positioned at the distal portion of the stent mounting region 90 to aspirate air out from inside the delivery system and from around the outer guide channel member 80, thereby reducing the chance of air embolisms. In addition, there may be a flushing pathway 74 in the outer diameter 75 of the inner member between the stent platform 91 and the proximal wire guide exit port 73, thereby improving flow of air out of the system in the area of the stent during air aspiration. Also, the flushing port 94 may be formed in the outer guide channel member 80 intermediate the stent mounting region 90 and the exit port 83. Furthermore, the outer guide channel member exit port 83 may comprise a slit 186 for the wire guide to exit the distal portion 13. In one embodiment, the distal end of the inner compression member 41 passageway 45 may comprise a valve 61 such as a simple flap or diaphragm type valve as previously explained for purging air from the interior of the delivery system in the area of the stent, and in a closed position may also act as an optional guide to direct the wire guide toward the slit 186. It should be understood that these venting structures are optional, and that the device may include one or more of these structures.
The inner compression member 41 may have the dimensions (diameter, length) a previously described. Similarly, the inner compression member 41 may comprise the materials as previously described. In one embodiment, the inner compression member 41 comprises a proximal end 40, a middle section 40′, and a distal mating end 48 having an outer engaging surface 48′. Like elements from the previous drawings, embodiments, and description from above are labeled the same.
The overall length of the distal mating end 48 may vary. In one embodiment, it is from about 1.0 mm to about 10.0 mm. In another embodiment, the distal mating end 48 is approximately 3.0 mm. Furthermore, the distal mating end 48 optionally comprises a decreasing height 148 (
While the decreasing height 148 may have a gradually smaller cross sectional area when compared to the cross sectional area at the inner compression member 41 (
According to the invention, the inner compression member distal mating end 48 and/or outer engaging surface 48′ further comprise a contoured configuration 48″ that is generally complementary to the cannula 95 (e.g.,
The decreasing height 148 and the contoured configuration 48″ may be achieved by swaging, stamping, forging, or rolling between two rollers. For example, rolling the shaft between rollers of a mill will help to prevent any lessening of strength (i.e., fatigue strength) that could result if the decreasing height 148 and/or the contoured configuration 48″ were machined. It should be understood that the shape of the inner compression member 41 can be chosen depending on the shape of the cannula 95, the outer guide channel member 80, and/or the inner guide channel member 70, and the decreasing height 148 and/or the contoured configuration 48″ (or other configurations) may vary along the longitudinal axis of the inner compression member 41. Furthermore, the degree of flatness of an inner compression member 41 can determine the flexibility in a certain direction.
Methods
Methods of manufacturing and of providing a medical device for delivering a self-expanding stent are also provided.
Materials and methods of manufacturing a suitable middle section delivery device 14 and distal portion 13 are described in Published U.S. Patent Application 2004/0116833 (Koto et al.) and in U.S. Pat. No. 6,589,227 (Sonderskov Klint, et al.; Assigned to Cook Incorporated of Bloomington, Ind. and William Cook Europe of Bjaeverskov, Denmark). The contents of the patent and patent application are incorporated herein by reference. Examples further include a multifilar embodiment and a “Flexor® sheath” as described above and shown in the figures, or other component. Furthermore, the “Flexor® sheath,” manufactured and sold by Cook Incorporated of Bloomington, Ind., may be adapted for use with the distal portion 13 and/or the middle section delivery device 14. The Flexor® sheath, as previously described and shown in the figures above, may be provided for the distal portion 13 and/or the middle section delivery device 14. In step 606, the insert interfacing ends 124, 134 are brought together (step 606). The interfacing ends 124, 134 are secured by a connector 110 (step 608).
A method of manufacturing and of providing a medical device for delivering a self-expanding stent need not be performed sequentially. For instance, in method 300, a self-expanding device 17 may be loaded (step 304) before the delivery system 10 is provided (step 302). In method 400, the adjacent corners of side C of the second sheet 401′ may be cut and the opposing sides A and B joined (step 406) to form an outer guide channel member 80 before the inner member is formed by joining opposing sides A and B of the first sheet 401 (step 404). In method 600, the distal portion 13 may be provided (step 604) before providing the middle section delivery device 14 (step 602).
It is intended that the foregoing detailed description of the delivery system and devices for the rapid insertion of self-expanding stents be regarded as illustrative rather than limiting, and that it be understood that it is the following claims, including all equivalents, that are intended to define the spirit and scope of this invention. Terms are to be given their reasonable plain and ordinary meaning. Also, the embodiment of any figure and features thereof may be combined with the embodiments depicted in other figures. Other features known in the art and not inconsistent with the structure and function of the present invention may be added to the embodiments.
While particular elements, embodiments and applications of the present invention have been shown and described, it will be understood, of course, that the invention is not limited thereto since modifications may be made by those skilled in the art, particularly in light of the foregoing teachings. Therefore, it is therefore contemplated by the appended claims to cover such modifications as incorporate those features which come within the spirit and scope of the invention.
The present patent document claims the benefit of the filing date under 35 U.S.C. §119(e) of United States Provisional Patent Application filed on Apr. 20, 2005 entitled, “Delivery System and Devices for the Rapid Insertion of Self-Expanding Devices,” and having an application Ser. No. 60/673,199, the disclosure of which is hereby incorporated by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 60673199 | Apr 2005 | US |
