Patent Description:
A wide variety of intracorporeal medical devices have been developed for medical use, for example, intravascular use. Some of these devices include guidewires, catheters, and the like. These devices are manufactured by any one of a variety of different manufacturing methods and may be used according to any one of a variety of methods. Of the known medical devices and methods, each has certain advantages and disadvantages. There is an ongoing need to provide alternative medical devices as well as alternative methods for manufacturing and using medical devices.

<CIT> discloses medical device delivery systems and methods for making and using such systems.

The present invention is directed to a medical delivery system as set forth in the claims. This disclosure provides design, material, manufacturing method, and use alternatives for medical devices. According to the invention, the delivery system for an implantable medical device includes an inner shaft having a proximal end region, a distal end region, a non-circular lumen extending therethrough. The delivery system also includes a tension resistance member extending at least partially between the proximal end region and the distal end region, a deployment catheter disposed along the outer surface of the shaft, and an actuation shaft disposed within the non-circular lumen. Further, the actuation shaft is coupled to the implantable medical device and translation of the actuation shaft shifts the implantable medical device from a first position to a second position. Additionally, the delivery system includes a first tubular member extending within the non-circular lumen, wherein the first tubular member is designed to accept a guidewire extending therein, and a second tubular member extending within the non-circular lumen, wherein the actuation shaft extends within the second tubular member.

Also disclosed herein is a method for delivering an implantable medical device, the system comprising:.

Diseases and/or medical conditions that impact the cardiovascular system are prevalent throughout the world. Traditionally, treatment of the cardiovascular system was often conducted by directly accessing the impacted part of the system. For example, treatment of a blockage in one or more of the coronary arteries was traditionally treated using coronary artery bypass surgery. As can be readily appreciated, such therapies are rather invasive to the patient and require significant recovery times and/or treatments. More recently, less invasive therapies have been developed, for example, where a blocked coronary artery could be accessed and treated via a percutaneous catheter (e.g., angioplasty). Such therapies have gained wide acceptance among patients and clinicians.

Some relatively common medical conditions may include or be the result of inefficiency, ineffectiveness, or complete failure of one or more of the valves within the heart. For example, failure of the aortic valve or the mitral valve can have a serious effect on a human and could lead to serious health condition and/or death if not dealt with properly. Treatment of defective heart valves poses other challenges in that the treatment often requires the repair or outright replacement of the defective valve. Such therapies may be highly invasive to the patient. Disclosed herein are medical devices that may be used for delivering a medical device to a portion of the cardiovascular system in order to diagnose, treat, and/or repair the system. At least some of the medical devices disclosed herein may be used to deliver and implant a replacement heart valve (e.g., a replacement aortic valve, replacement mitral valve, etc.). In addition, the devices disclosed herein may deliver the replacement heart valve percutaneously and, thus, may be much less invasive to the patient. The devices disclosed herein may also provide a number of additional desirable features and benefits as described in more detail below.

The figures illustrate selected components and/or arrangements of a medical device system <NUM>, shown schematically in <FIG> for example. It should be noted that in any given figure, some features of the medical device system <NUM> may not be shown, or may be shown schematically, for simplicity. Additional details regarding some of the components of the medical device system <NUM> may be illustrated in other figures in greater detail. A medical device system <NUM> may be used to deliver and/or deploy a variety of medical devices to a number of locations within the anatomy. In at least some embodiments, the medical device system <NUM> may include a replacement heart valve delivery system (e.g., a replacement aortic valve delivery system) that can be used for percutaneous delivery of a medical implant <NUM>, such as a replacement/prosthetic heart valve. This, however, is not intended to be limiting as the medical device system <NUM> may also be used for other interventions including valve repair, valvuloplasty, delivery of an implantable medical device (e.g., such as a stent, graft, etc.), and the like, or other similar interventions.

The medical device system <NUM> may generally be described as a catheter system that includes an outer sheath <NUM>, an inner catheter <NUM> (a portion of which is shown in <FIG> in phantom line) extending at least partially through a lumen of the outer sheath <NUM>, and a medical implant <NUM> (e.g., a replacement heart valve implant) which may be coupled to the inner catheter <NUM> and disposed within a lumen of the outer sheath <NUM> during delivery of the medical implant <NUM>. In some embodiments, a medical device handle <NUM> may be disposed at a proximal end of the outer sheath <NUM> and/or the inner catheter <NUM> and may include one or more actuation mechanisms associated therewith. In other words, a tubular member (e.g., the outer sheath <NUM>, the inner catheter <NUM>, etc.) may extend distally from the medical device handle <NUM>. In general, the medical device handle <NUM> may be designed to manipulate the position of the outer sheath <NUM> relative to the inner catheter <NUM> and/or aid in the deployment of the medical implant <NUM>.

In use, the medical device system <NUM> may be advanced percutaneously through the vasculature to a position adjacent to an area of interest and/or a treatment location. For example, in some embodiments, the medical device system <NUM> may be advanced through the vasculature to a position adjacent to a defective native valve (e.g., aortic valve, mitral valve, etc.). Alternative approaches to treat a defective aortic valve and/or other heart valve(s) are also contemplated with the medical device system <NUM>. During delivery, the medical implant <NUM> may be generally disposed in an elongated and low profile "delivery" configuration within the lumen and/or a distal end of the outer sheath <NUM>, as seen schematically in <FIG> for example. Once positioned, the outer sheath <NUM> may be retracted relative to the medical implant <NUM> and/or the inner catheter <NUM> to expose the medical implant <NUM>. In some instances, the medical implant <NUM> may be self-expanding such that exposure of the medical implant <NUM> may deploy the medical implant <NUM>. Alternatively, the medical implant <NUM> may be expanded/deployed using the medical device handle <NUM> in order to translate the medical implant <NUM> into a generally shortened and larger profile "deployed" configuration suitable for implantation within the anatomy. For example, in some instances the inner catheter (or components thereof) may be coupled to medical implant <NUM> whereby actuation of the inner catheter <NUM> relative to the outer sheath <NUM> and/or the medical implant <NUM> may deploy the medical device <NUM> within the anatomy. When the medical implant <NUM> is suitably deployed within the anatomy, the medical device system <NUM> may be disconnected, detached, and/or released from the medical implant <NUM> and the medical device system <NUM> can be removed from the vasculature, leaving the medical implant <NUM> in place in a "released" configuration.

It can be appreciated that during delivery and/or deployment of an implantable medical device (e.g., the medical implant <NUM>), portions of the medical device system <NUM> may be required to be advanced through tortuous and/or narrow body lumens. Therefore, it may be desirable to utilize components and design medical delivery systems (e.g., such as the medical device system <NUM> and/or other medical devices) that reduce the profile of portions of the medical device while maintaining sufficient strength (compressive, torsional, etc.) and flexibility of the system as a whole.

<FIG> illustrates a portion of an example shaft <NUM> that may reduce the profile of portions of the medical device while maintaining sufficient strength (compressive, torsional, etc.) and flexibility of the system as a whole. In some instances, the shaft <NUM> may be used as the inner catheter <NUM> in the medical device system <NUM> illustrated in <FIG>. However, the shaft <NUM> may be other components of the medical device system <NUM>, a component of a different medical device system (e.g., a stent delivery system, an angioplasty system, a biopsy system, etc.), any other medical device where reduced profile designs may be required, or the like.

The shaft <NUM> includes an inner member or the liner <NUM>, which is also referred to as the inner shaft. The inner liner <NUM> may include a number of features as discussed herein. A deployment catheter or outer member <NUM> is disposed along the outer surface of the inner liner <NUM>. The outer member <NUM> may be designed to translate and/or rotate relative to the liner <NUM>. For example, it can be appreciated that as the shaft <NUM> is advanced through the anatomy, the liner <NUM> may translate longitudinally or radially twist within the outer member <NUM>.

The inner liner <NUM> may include a number of features. In accordance with the invention, the inner liner <NUM> includes a tension resistance member <NUM>. In one example, the inner liner <NUM> may include a pair of tension resistance members 30a/30b or more. The tension resistance members 30a/30b may take the form of a wire (e.g., a metallic wire), a braid, cable, stranded cable, a composite structure, or the like. In one example, the tension resistance members 30a/30b are both metallic wires. In another instance, the tension resistance members 30a/30b are both metallic braids. The braids may further includes an axial wire made from a suitable polymer or metal (e.g., aramid). The tension resistance members 30a/30b may be made from the same materials and/or have the same configuration. Alternatively, the tension resistance members 30a/30b may be different from one another. Furthermore, while <FIG> illustrates that the inner liner <NUM> includes two tension resistance members 30a/30b, this is not intended to be limiting. Other numbers of tension resistance members 30a/30b are contemplated such as one, three, four, five, six, seven, or more.

The inner liner <NUM> also includes a lumen <NUM>. A first tubular member <NUM> is disposed within the lumen <NUM>. The first tubular member <NUM> defines a guidewire lumen <NUM>, through which a guidewire <NUM> extends. A second tubular member <NUM> is also disposed within the lumen <NUM>. The second tubular member <NUM> defines a lumen <NUM> through which an actuation shaft or actuation member <NUM> extends. As described above, the actuation member <NUM> is coupled and/or attached to the medical implant <NUM>. Translation of the actuation member 40shifts the implant <NUM> from a first collapsed configuration to a second deployed configuration.

<FIG> illustrates the liner <NUM> described with respect to <FIG>. As shown in <FIG> and described above, the liner <NUM> may include a pair of tension resistance members 30a/30b which are positioned on opposite sides of the lumen <NUM>. <FIG> further illustrates that the shape of the lumen <NUM> may be designed to limit twisting of the first tubular member <NUM> and the second tubular member <NUM> relative to one another. In accordance with the invention, <FIG> illustrates that the lumen <NUM> is non-circular. For example, the shape of the lumen <NUM> may be ovular, square, rectangular, triangular, combinations thereof, etc. These are just examples. The inner liner <NUM> may vary in form. For example, the inner liner <NUM> may include various shapes in combination with a single lumen or multiple lumens. Further, the liner <NUM> may lack a lumen.

It can be appreciated that as the liner <NUM> rotates within the lumen of the outer member <NUM>, the non-circular shape of the lumen <NUM> may force both the first tubular member <NUM> and the second tubular member <NUM> to maintain their respective spatial relationship as depicted in <FIG>. In other words, the shape of the lumen <NUM> forces the first tubular member <NUM> and the second tubular member <NUM> to remain in their respective positions relative to one another independent of the bending, rotating, flexing, etc. of the liner <NUM>.

While <FIG> illustrates that the lumen <NUM> is designed to accommodate a first tubular member <NUM> and a second tubular member <NUM>, it is contemplated that the lumen <NUM> may be configured to accommodate more than two individual tubular members. For example, the lumen <NUM> may be shaped to accommodate two, three, four, five, six, seven, eight or more lumens. Further, it is contemplated that the particular shape of the lumen <NUM> may be designed to match the outer profile of any number of lumens collectively grouped together. For example, while not depicted in the figures, it can be appreciated that a triangular-shaped lumen <NUM> may match the outer profile of three circular tubular members grouped together at approximately <NUM> degrees offset from one another. This is not intended to be limiting. Rather, the lumen <NUM> may be shaped to match the profile of any collection of tubular members having any given outer profile. As discussed above, matching the shape of the lumen <NUM> with the profile of the tubular members positioned therein limits the ability of the tubular members from twisting around one another within the lumen <NUM>.

It can be further appreciated that varying the shape of the lumen <NUM> may contribute to reducing the overall profile of the liner <NUM>, and by extension, the overall profile of the shaft <NUM>. For example, varying the shape of the lumen <NUM> may permit the reduction in the wall thickness separating individual lumens extending within the liner <NUM>. Reducing the wall thickness separating the individual lumens may permit the overall profile of the liner <NUM> and/or the shaft <NUM> to be much smaller than existing liners/shaft designs.

Additionally, it can be appreciated that it may be desirable to vary the shape of the profile of the outer surface of liner <NUM>. For example, <FIG> illustrates another example liner <NUM>. Liner <NUM> may be similar in form and function to other liners discussed herein. For example, liner <NUM> may include an inner lumen <NUM> and two tension resistance members 130a/130b. However, as shown in <FIG>, liner <NUM> may also an outer surface profile that includes one or more longitudinally extending channels <NUM> (e.g., grooves, troughs, etc.) extending along the length thereof. As shown in <FIG>, each of the channels <NUM> may include a curved portion that, in some examples, follows the profile of the inner lumen <NUM> and two tension resistance members 130a/130b.

<FIG> illustrates a cross-sectional view of the inner liner <NUM> shown in <FIG>. However, <FIG> further illustrates an outer member <NUM> (which may be similar in form and function to outer member <NUM> discussed above) positioned over the inner liner <NUM>. It can be appreciated from <FIG> that one or more of the channels <NUM> may create one or more "pseudo-lumens" (e.g., space, opening, aperture, etc.) extending the length of liner <NUM> and outer member <NUM> between the outer surface of inner liner <NUM> and the inner surface of outer member <NUM>. In some instances, it may be desirable to extend (e.g., position) wires, cables, etc. through the channels <NUM>. It is contemplated that the wires, cables, etc. which may be extended through channels <NUM> may be in addition to the two tension resistance members 130a/130b.

The materials that can be used for the various components of the medical devices and/or systems disclosed herein (e.g., shaft <NUM> and/or other shafts disclosed herein) may include those commonly associated with medical devices. For simplicity purposes, the following discussion makes reference to the shaft <NUM>. However, this is not intended to limit the devices and methods described herein, as the discussion may be applied to other shafts and/or components of the medical devices and/or systems disclosed herein including the various bead members, barrel members, etc..

The shaft <NUM> may be made from a metal, metal alloy, polymer (some examples of which are disclosed below), a metal-polymer composite, ceramics, combinations thereof, and the like, or other suitable material. Some examples of suitable polymers may include polytetrafluoroethylene (PTFE), ethylene tetrafluoroethylene (ETFE), fluorinated ethylene propylene (FEP), polyoxymethylene (POM, for example, DELRIN® available from DuPont), polyether block ester, polyurethane (for example, Polyurethane 85A), polypropylene (PP), polyvinylchloride (PVC), polyether-ester (for example, ARNITEL® available from DSM Engineering Plastics), ether or ester based copolymers (for example, butylene/poly(alkylene ether) phthalate and/or other polyester elastomers such as HYTREL® available from DuPont), polyamide (for example, DURETHAN® available from Bayer or CRISTAMID® available from Elf Atochem), elastomeric polyamides, block polyamide/ethers, polyether block amide (PEBA, for example available under the trade name PEBAX®), ethylene vinyl acetate copolymers (EVA), silicones, polyethylene (PE), high density polyethylene (HDPE), polyester, Marlex high-density polyethylene, Marlex low-density polyethylene, linear low density polyethylene (for example REXELL®), ultra-high molecular weight (UHMW) polyethylene, polypropylene, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polytrimethylene terephthalate, polyethylene naphthalate (PEN), polyetheretherketone (PEEK), polyimide (PI), polyetherimide (PEI), polyphenylene sulfide (PPS), polyphenylene oxide (PPO), poly paraphenylene terephthalamide (for example, KEVLAR®), polysulfone, nylon, nylon-<NUM> (such as GRILAMID® available from EMS American Grilon), perfluoro(propyl vinyl ether) (PFA), ethylene vinyl alcohol, polyolefin, polystyrene, epoxy, polyvinylidene chloride (PVdC), poly(styrene-b-isobutylene-b-styrene) (for example, SIBS and/or SIBS 50A), polycarbonates, ionomers, biocompatible polymers, other suitable materials, or mixtures, combinations, copolymers thereof, polymer/metal composites, and the like. In some embodiments the sheath can be blended with a liquid crystal polymer (LCP).

Some examples of suitable metals and metal alloys include stainless steel, such as 304V, <NUM>, and 316LV stainless steel; mild steel; nickel-titanium alloy such as linear-elastic and/or super-elastic nitinol; other nickel alloys such as nickel-chromium-molybdenum alloys (e.g., UNS: N06625 such as INCONEL® <NUM>, UNS: N06022 such as HASTELLOY® C-<NUM>, UNS: N10276 such as HASTELLOY® C276®, other HASTELLOY® alloys, and the like), nickel-copper alloys (e.g., UNS: N04400 such as MONEL® <NUM>, NICKELVAC® <NUM>, NICORROS® <NUM>, and the like), nickel-cobalt-chromium-molybdenum alloys (e.g., UNS: R30035 such as MP35-N® and the like), nickel-molybdenum alloys (e.g., UNS: N10665 such as HASTELLOY® ALLOY B2®), other nickel-chromium alloys, other nickel-molybdenum alloys, other nickel-cobalt alloys, other nickel-iron alloys, other nickel-copper alloys, other nickel-tungsten or tungsten alloys, and the like; cobalt-chromium alloys; cobalt-chromium-molybdenum alloys (e.g., UNS: R30003 such as ELGILOY®, PHYNOX®, and the like); platinum enriched stainless steel; titanium; combinations thereof; and the like; or any other suitable material.

In at least some embodiments, portions or all of the shaft may also be doped with, made of, or otherwise include a radiopaque material. Radiopaque materials are understood to be materials capable of producing a relatively bright image on a fluoroscopy screen or another imaging technique during a medical procedure. This relatively bright image aids the user of the shaft in determining its location. Some examples of radiopaque materials can include, but are not limited to, gold, platinum, palladium, tantalum, tungsten alloy, polymer material loaded with a radiopaque filler, and the like. Additionally, other radiopaque marker bands and/or coils may also be incorporated into the design of the shaft <NUM> to achieve the same result.

In some embodiments, a degree of Magnetic Resonance Imaging (MRI) compatibility is imparted into the shaft. For example, the shaft <NUM> may include a material that does not substantially distort the image and create substantial artifacts (e.g., gaps in the image). Certain ferromagnetic materials, for example, may not be suitable because they may create artifacts in an MRI image. The shaft <NUM> may also be made from a material that the MRI machine can image. Some materials that exhibit these characteristics include, for example, tungsten, cobalt-chromium-molybdenum alloys (e.g., UNS: R30003 such as ELGILOY®, PHYNOX®, and the like), nickel-cobalt-chromium-molybdenum alloys (e.g., UNS: R30035 such as MP35-N® and the like), nitinol, and the like, and others.

Claim 1:
A delivery system (<NUM>) for an implantable medical device (<NUM>), comprising:
an inner shaft (<NUM>) having a proximal end region, a distal end region, a non-circular lumen (<NUM>) extending therethrough, and a tension resistance member (30a/30b) extending at least partially between the proximal end region and the distal end region;
a deployment catheter (<NUM>) disposed along the outer surface of the shaft; and
an actuation shaft (<NUM>) disposed within the non-circular lumen (<NUM>);
wherein the actuation shaft is coupled to the implantable medical device (<NUM>);
wherein translation of the actuation shaft shifts the implantable medical device (<NUM>) from a first collapsed position to a second deployed position;
a first tubular member (<NUM>) extending within the non-circular lumen (<NUM>); wherein the first tubular member (<NUM>) is designed to accept a guidewire (<NUM>) extending therein; and
a second tubular member (<NUM>) extending within the non-circular lumen (<NUM>); wherein the actuation member (<NUM>) extends within the second tubular member (<NUM>).