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 and catheters. 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 an apparatus for delivering stents or stent segments to body lumens. <CIT> discloses a catheter system with electrodes.

The present invention is directed to a delivery system for an implantable medical device as set forth in the claims.

The delivery system in accordance with the invention includes an outer shaft defining an outer shaft lumen and an inner shaft that is translatable within the outer shaft lumen and that defines a lumen extending through the inner shaft. An internally exposed coil is disposed within the inner shaft and is electrically coupled to an externally exposed coil that can be used to conductively transmit a current flowing through the internally exposed coil. An actuation mechanism extends through the lumen and includes a coupler, a force translation rod that extends proximally from the coupler and a plurality of push pull rods that extend distally from the coupler and that releasably couple to the implantable medical device. The force translation rod is formed of an electrically conducting material with an electrically insulating outer layer, with one or more etched areas extending through the electrically insulating outer layer, wherein when the force translation rod moves relative to the inner shaft, and thus the one or more etched areas move relative to the internally exposed coil, an impedance varies in accordance with relative position.

The delivery system may further include a detection region formed in the inner shaft and disposed relative to the internally exposed coil.

The delivery system may further include a front seal disposed at a front edge of the detection region and a rear seal disposed at a rear edge of the detection region.

The front seal and/or the back seal may include an O-ring.

The force translation rod may include an etched or otherwise exposed proximal end so that electrical contact can be made with the force translation rod.

The electrically insulating outer layer on the force translation rod may include a polymer.

The electrically insulating outer layer on the force translation rod may include Parylene or expanded polytetrafluoroethylene.

Each of the one or more etched areas may be electrically conductive.

Each of the one or more etched areas may be located a known distance from the coupler.

Another delivery system in accordance with the invention includes an outer shaft defining an outer shaft lumen and an inner shaft that is translatable within the outer shaft lumen. The inner shaft defines a lumen extending through the inner shaft. An actuation mechanism extends through the lumen and includes a coupler, a force translation rod that extends proximally from the coupler and a plurality of push pull rods that extend distally from the coupler and that releasably couple to the implantable medical device. The force translation rod is formed of or including an electrically conducting material with an electrically insulating outer layer, with one or more electrically conductive etched areas extending through the electrically insulating outer layer. A resilient switch is coupled to the inner shaft and is positioned to slidingly engage the force translation rod such that as the force translation rod translates, the resilient switch comes into contact with the one or more electrically conductive etched areas. When the force translation rod moves relative to the inner shaft, and thus the one or more etched areas move relative to the internally exposed coil, an impedance varies in accordance with relative position.

The force translation rod may include an etched or selectively electrically active proximal end so that electrical contact can be made with the force translation rod.

The inner shaft may include an outer surface, and the outer surface may include one or more longitudinally extending slots that accommodate electrical conductors within the one or more longitudinally extending slots.

The one or more electrically conducting etched areas may include a plurality of etched bars extending radially at least partially around the force translation rod.

The plurality of etched bars extending radially at least partially around the force translation rod may be arranged with a non-uniform axial spacing between adjacent etched bars.

Another delivery system in accordance with the invention includes an outer shaft defining an outer shaft lumen and an inner shaft that is translatable within the outer shaft lumen and that itself defines a lumen extending through the inner shaft. An actuation mechanism extends through the lumen and includes a coupler, a force translation rod that extends proximally from the coupler and a plurality of push pull rods that extend distally from the coupler and that releasably couple to the implantable medical device. The force translation rod includes one or more ferromagnetic segments disposed along a length of the force translation rod. An electromagnetic detector is coupled to the inner shaft and is positioned to slidingly engage the force translation rod such that as the force translation rod translates, the electromagnetic detector comes into proximity with the one or more ferromagnetic segments disposed along the length of the force translation rod.

The inner shaft may define an outer surface, and the outer surface may include one or more longitudinally extending slots, and the electromagnetic switch is disposed within one of the one or more longitudinally extending slots.

Each of the one or more ferromagnetic segments may be located a known distance from the coupler.

On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the scope of the disclosure.

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). 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 for example valve repair, valvuloplasty, delivery of an implantable medical device (e.g., such as a stent, graft) or other similar interventions.

The medical device system <NUM> in accordance with the invention can generally be described as a catheter system that includes an outer sheath <NUM> (also referred to as an outer shaft), an inner catheter <NUM> (a portion of which is shown in <FIG> in phantom line, also referred to as an inner shaft) 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>) 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> is advanced percutaneously through the vasculature to a position adjacent to an area of interest and/or a treatment location. For example, 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> generally is 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> is 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. 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 (e.g. compressive, torsional) and flexibility of the system as a whole.

<FIG> illustrates the medical device system <NUM> in a partially deployed configuration. As illustrated in <FIG>, the outer sheath <NUM> of the medical device system <NUM> has been retracted in a proximal direction to a position proximal of the medical implant <NUM>. In other words, the outer sheath <NUM> has been retracted (e.g., pulled back) in a proximal direction such that it uncovers the medical device implant <NUM> from a compact, low-profile delivery position to a partially deployed position.

In at least some examples contemplated herein, the medical device implant <NUM> may be designed to self-expand once released from under the outer sheath <NUM>. However, as shown in <FIG>, the medical device system <NUM> may be designed such that the implant <NUM> may be restricted from expanding fully in the radial direction. For example, <FIG> shows medical device implant <NUM> having a partially deployed position denoted as a length "L<NUM>.

<FIG> further illustrates that the implant <NUM> may include one or more support members <NUM> coupled to the proximal end <NUM> of the implant <NUM>. Further, <FIG> illustrates that the implant <NUM> includes one or more translation members <NUM> (also referred to as push pull rods) coupled to the distal end <NUM> of the implant <NUM>. Additionally, in some examples (such as that illustrated in <FIG>), the translation members <NUM> and support members <NUM> may work together to maintain the implant in a partially deployed position after the outer sheath has been retracted to uncover the implant <NUM>. For example, <FIG> illustrates that the support members <NUM> may be designed such that the distal end of each of the support members may be coupled to the proximal end of the implant <NUM> and that the proximal end of each of the support members <NUM> may be coupled to the distal end of the inner catheter <NUM>. For example, <FIG> illustrates that the proximal ends of the support members <NUM> may be attached to a containment fitting <NUM> which is rigidly fixed to the distal end of the inner catheter <NUM>. It can be further appreciated that in some instances, the support members <NUM> may be designed to limit the proximal movement of the proximal end <NUM> of the implant <NUM> relative to the distal end of the inner catheter <NUM>.

The translation members <NUM> are designed to translate in a distal-to-proximal direction such that the translation of the translation members (via operator manipulation at the handle, for example) may "pull" the distal end <NUM> of the implant closer to the proximal end <NUM> of the implant <NUM>.

<FIG> illustrates the distal-to-proximal translation of the translation members <NUM>. It can be appreciated that if the support members <NUM> limit the proximal movement of the proximal end <NUM> of the implant <NUM> while the translation members <NUM> are translated proximally, the implant <NUM> may both foreshorten (along the longitudinal axis of the implant <NUM>) and also expand radially outward. The foreshortening and radial expansion of implant <NUM> can be seen by comparing the shape and position of the implant <NUM> in <FIG> to the shape and position of the implant <NUM> in <FIG>. The position of the implant <NUM> shown in <FIG> may be described as a fully deployed positioned of the implant <NUM> (versus the partially deployed positioned of the implant <NUM> shown in <FIG>). Further, <FIG> depicts the length of the fully deployed implant <NUM> as L<NUM>, whereby the distance L<NUM> is less than the distance L<NUM> shown in <FIG>.

Additionally, it can be appreciated that the translation members <NUM> may be designed to be able to extend in a proximal-to-distal direction such that they elongate (e.g., lengthen) the implant <NUM> (along its longitudinal axis). In other words, implant <NUM> may be able to shift between a partially deployed position (shown in <FIG>) and a fully deployed position (shown in <FIG>) through the translation (either proximal or distal) of the translation members <NUM> along the longitudinal axis as the support members <NUM> limit the movement of the proximal end <NUM> of the implant <NUM>.

It should be noted that the above description and illustrations regarding the arrangement, attachment features and operation of the support members <NUM> and the translation members <NUM> as they engage and function relative to the implant <NUM> is schematic. It can be appreciated that the design (e.g., arrangement, attachment features, operation) of both the support member <NUM> and the translation members <NUM> as they relate and function relative to the implant <NUM> may vary. For example, it is possible to design, arrange and operate the translation members <NUM> and the support members <NUM> in a variety of ways to achieve the partial and full deployment configurations of the implant <NUM>.

In some examples, an operator may be able to manipulate the translation members <NUM> via the handle member <NUM>. For example, the handle <NUM> may include an actuation member designed to control the translation of the translation members <NUM>. <FIG> illustrates that the handle member <NUM> may be coupled to the translation members <NUM> via an actuation shaft <NUM> and a coupling member <NUM> (also referred to a s a coupler). <FIG> illustrates that the proximal ends of the translation members <NUM> are coupled to a distal end of the coupling member <NUM>. <FIG> further illustrates that a distal end of actuation shaft <NUM> is coupled to the proximal end of the coupling member <NUM>. Further, while not shown in <FIG>, it can be appreciated that the actuation shaft <NUM> may extend within the entire length of the inner shaft <NUM> from the coupling member <NUM> to the handle member <NUM>.

For purposes of discussion herein, the inner shaft <NUM> may also be referred to as an inner member or liner <NUM>. The liner <NUM> may include a number of different features shown in the figures described herein. In accordance with the invention, the liner or inner shaft includes a lumen <NUM>. Further, the translation members <NUM>, coupler <NUM>, actuation shaft <NUM>, guidewire lumen <NUM> (described below), and grouping coil <NUM> (described below) may be disposed within the lumen <NUM>. These are just examples. The inner liner <NUM> may vary in form. For example, the inner liner <NUM> may include a single lumen or multiple lumens.

As described above, <FIG> and <FIG> illustrate the translation of translation members <NUM> in a distal-to-proximal direction (which shortens and radially expands the implant <NUM>, as described above). However, <FIG> further illustrates that translation of the translation members <NUM> in a distal-to-proximal direction is accomplished by translation of the actuation shaft <NUM> and coupling member <NUM> within the lumen <NUM> of the inner catheter <NUM>. For example, as the actuation shaft <NUM> is retracted (e.g., pulled proximally within lumen <NUM> of the inner catheter <NUM>), it retracts the coupling member <NUM> proximally, which, in turn, retracts the translation members <NUM> in a proximal direction.

In some instances it may be desirable to maintain translation members <NUM> in a substantially linear configuration as they are translated within the lumen <NUM> of the inner catheter <NUM>. In some examples, therefore, medical device system <NUM> may include a component designed to limit and/or prevent the translation members <NUM> from twisting around each other within the lumen <NUM> of the inner catheter <NUM>. For example, <FIG> and <FIG> illustrate a grouping coil <NUM> wound around the translation members <NUM> such that the grouping coil maintains the translation members <NUM> in a substantially linear configuration (and thereby limits and/or prevents the translation members <NUM> from twisting within lumen <NUM>) as the translation members <NUM> are translated through the lumen <NUM> of the inner catheter <NUM>.

<FIG> and <FIG> further illustrate that the proximal end of the grouping coil <NUM> may be positioned adjacent the distal end of the coupling member <NUM> and that the distal end of the grouping coil <NUM> may be positioned adjacent the distal end of the inner catheter <NUM>. In particular, the distal end of the grouping coil <NUM> may be prevented from extending distally beyond the distal end of the inner catheter <NUM> by the containment fitting <NUM>. In other words, the distal end of the grouping coil <NUM> may contact the containment fitting <NUM>.

It can be further appreciated that the grouping coil <NUM> may be positioned within the lumen <NUM> of the inner catheter <NUM> such that the grouping coil <NUM> may elongate and shorten (e.g., a length of the grouping coil may adjust) within the lumen <NUM> of the inner catheter <NUM>. For example, as the coupling member <NUM> is translated in a proximal direction (shown in <FIG> as compared to <FIG>), the grouping coil may elongate while continuing to group and/or contain the translation members <NUM> in a substantially linear configuration.

<FIG> and <FIG> further illustrate that the medical device system <NUM> may include a tubular guidewire member <NUM> extending within the lumen <NUM> of the inner catheter <NUM>. The tubular guidewire member <NUM> may be designed to permit a guidewire to extend and translate therein. Further, the tubular guidewire member <NUM> may extend from the handle member <NUM>, through the lumen <NUM> of the inner member <NUM>, through the implant <NUM> and terminate at a nosecone <NUM>. Additionally the tubular guidewire member <NUM> may include a lumen (not shown in <FIG> or <FIG>) that permits a guidewire to be advanced therein. In other words, the medical device <NUM> may be advanced to a target site within a body over a guidewire extending within the lumen of the tubular guidewire member <NUM>.

<FIG> illustrates a cross-section of a portion of the medical device system <NUM> described with respect to <FIG>. In particular, as described above, <FIG> illustrates the actuation shaft <NUM> coupled to coupler <NUM>, translation members <NUM> coupled to coupler <NUM> and grouping coil <NUM> (the distal end of which is positioned adjacent the containment fitting <NUM>, as described above) wound around the translation members <NUM>. <FIG> further illustrates that the outer surface <NUM> of the grouping coil <NUM> may contact both the inner surface <NUM> of the inner catheter <NUM> and the outer surface <NUM> of the guidewire member <NUM>. Therefore, it can be further appreciated that the outer diameter (and therefore the inner diameter) of the grouping coil <NUM> may remain constant as the grouping coil lengthens or shortens as the coupler <NUM> translates within the lumen <NUM> of the inner catheter <NUM>.

Additionally, it can be appreciated that the medical device system <NUM> may be designed such that both the proximal end and the distal end of the grouping coil <NUM> may not be fixedly attached to adjacent structures (e.g., may not be attached to the coupling member <NUM> and/or the containment fitting <NUM>). It can be appreciated that by not attaching either end of the grouping coil <NUM> to an adjacent structures (e.g., the coupling member <NUM> and/or the containment fitting <NUM>), the grouping coil <NUM> is permitted to twist freely while lengthening or shortening within the lumen <NUM>. This freedom of movement allows the grouping coil <NUM> to maintain an inner diameter which tightly groups (e.g., contains) the translation members <NUM> to each other as that translate linearly within the lumen <NUM> of inner catheter <NUM>.

<FIG> further illustrates that coupler <NUM> may be positioned within the lumen <NUM> of the inner catheter <NUM> such that the bottom surface <NUM> of the coupler <NUM> is adjacent to the outer surface <NUM> of the guidewire member <NUM>. In some examples, the coupler <NUM> may be designed such that it is not rigidly fixed to the guidewire member <NUM>, and therefore, may translate relative to the guidewire member <NUM>. In other examples, the coupler <NUM> may be designed such that it is rigidly fixed to the guidewire member <NUM>, and therefore, translation of coupler <NUM> (which itself may occur via translation of the actuation shaft <NUM>) may also translate both the guidewire member <NUM> and the translation members <NUM>. In other words, it can be appreciated that in instances where the coupler <NUM> is rigidly fixed to the guidewire member <NUM>, an operator manipulating the actuation shaft <NUM> via handle <NUM> may translate both the translation members <NUM> and the guidewire member <NUM> together such that distal or proximal translation of either the translation members <NUM> or the guidewire member <NUM> will translate both the translation members <NUM> or the guidewire member <NUM> a correspondingly equal amount. Further, it can be appreciated the same effect may be achieved by coupling the guidewire member <NUM> and the actuation shaft <NUM> anywhere along medical device system <NUM>, including coupling the guidewire member <NUM> and the actuation shaft <NUM> to one another in the handle member <NUM>. It can be appreciated that the guidewire member <NUM> and the actuation shaft <NUM> may be coupled together in more than one location along medical device system <NUM>.

In some instances, it may be desirable for the nosecone <NUM> to translate in a proximal direction as the implantable medical device <NUM> shifts from a collapsed configuration to a fully deployed configuration (as shown in <FIG>). It can be appreciated from the above discussion that because the nosecone <NUM> is connected to the distal end of the guidewire member <NUM>, that as the guidewire member <NUM> translates with the translation members <NUM> (via the coupler <NUM> and actuation shaft <NUM>), the nosecone <NUM> with correspondingly translate in a proximal direction as the translational members act to shift the implantable medical device <NUM> from a collapsed to a fully deployed configuration.

<FIG> further illustrates that in some instances actuation shaft <NUM> may include an actuation rod <NUM> positioned within the lumen of a coil member <NUM>. Similar to that described above with respect to the grouping coil <NUM>, the outer surface of the coil member <NUM> may contact both the inner surface <NUM> of the inner catheter <NUM> and the outer surface <NUM> of the guidewire member <NUM>. It can be appreciated that the outer surface of the coil member <NUM> may reduce the frictional forces of actuation shaft <NUM> along the inner surface <NUM> of the inner catheter <NUM> as compared to the frictional forces that would be present if the actuation shaft <NUM> did not include a coil member. For example, coil member <NUM> provides both "point to point" contacts along the inner surface <NUM> of the inner member <NUM> in addition to increasing the ease with which the actuation shaft flexes/bends within the lumen <NUM> of inner catheter <NUM>. These properties reduce the overall surface friction between the outer surface of actuation shaft <NUM> and the inner surface <NUM> of inner catheter <NUM> (as compared to a solid rod of similar proportions). The reduction in friction may further reduce the likelihood of the actuation shaft <NUM> to store and release energy in the form of a "backlash" effect. It is contemplated that the coil member <NUM> may be extend along a portion of or the entire length of the actuation rod <NUM>. Further, the actuation rod <NUM> may extend from the proximal end of the coupler <NUM> to the handle member <NUM>. Additionally, the above described functional characteristics of the coil member <NUM> are not intended to be limiting. For example, it is contemplated that the coil member <NUM> may be utilized to conduct electricity along a portion thereof (e.g., along the surface or other portion of coil member <NUM>).

<FIG> further illustrates that in some examples guidewire member <NUM> may include a reinforcing coil embedded with its tubular wall. For example, <FIG> shows coil <NUM> positioned with the wall of guidewire member <NUM>. Coil <NUM> may provide additional strength and flexibility to the guidewire member <NUM>. Additionally, <FIG> illustrates the lumen <NUM> of the guidewire member <NUM>. It can be appreciated that a guidewire (not shown) may extend with the lumen <NUM> of the guidewire member <NUM>.

<FIG> illustrates a cross-sectional view along line <NUM>-<NUM> of <FIG>. As indicated above, the inner catheter <NUM> may include a number of features. For example, the inner catheter <NUM> may include one or more tension resistance members 50a/50b. The tension resistance members 50a/50b may take the form of for example a wire (e.g., a metallic wire), a braid, cable, stranded cable, a composite structure. In one example, the tension resistance members 50a/50b are both metallic wires. In another instance, the tension resistance members 50a/50b are both metallic braids. The braids may further include an axial wire made from a suitable polymer or metal (e.g., aramid). The tension resistance members 50a/50b may be made from the same materials and/or have the same configuration. Alternatively, the tension resistance members 50a/50b may be different from one another. Furthermore, while <FIG> illustrates that the inner catheter <NUM> includes two tension resistance members 50a/50b, this is not intended to be limiting. Other numbers of tension resistance members 50a/50b are contemplated such as one, three, four, five, six, seven, or more.

<FIG> further illustrates that the shape of the lumen <NUM> of the inner catheter <NUM> may be designed to limit twisting of the actuation shaft <NUM> and the guidewire member <NUM>. For example, <FIG> illustrates that lumen <NUM> may be non-circular. For example, the shape of the lumen <NUM> may be ovular, square, rectangular. It can be appreciated that as the inner catheter <NUM> rotates within the lumen of the outer member <NUM>, the shape of the lumen <NUM> may force both the actuation shaft <NUM> and the guidewire member <NUM> to maintain the respective spatial relationship as depicted in <FIG>. In other words, the shape of the lumen <NUM> forces the actuation shaft <NUM> and the guidewire member <NUM> to remain in their positions relative to one another independent of for example the bending, rotating, flexing of the inner catheter <NUM>.

Additionally, <FIG> also illustrates the actuation shaft <NUM> and the guidewire member positioned adjacent one another within lumen <NUM>. As described above, actuation shaft <NUM> may include an actuation rod <NUM> positioned within the lumen of a coil member <NUM>. Additionally, <FIG> shows guidewire member <NUM>. The guidewire member <NUM> may include a reinforcing coil <NUM> embedded with its tubular wall. For example, <FIG> shows coil <NUM> positioned with the wall of guidewire member <NUM>. Coil <NUM> may provide additional strength and flexibility to the guidewire member <NUM>. Additionally, <FIG> illustrates the lumen <NUM> of the guidewire member <NUM>.

<FIG> illustrates a cross-sectional view along line <NUM>-<NUM> of <FIG> shows grouping coil <NUM>, coupler <NUM> and guidewire member <NUM> positioned within lumen <NUM>. Additionally, <FIG> shows that the grouping coil <NUM> may surround three translational members <NUM> positioned therein. The translational members <NUM> may be spaced equidistance from one another. For example, the translational members <NUM> may be spaced at substantially <NUM>-degree angles relative to one another. Further, while <FIG> shows three translational members <NUM>, it is contemplated that more or less than three translational members <NUM> may be utilized within medical device system <NUM>. For example, medical device system <NUM> may include <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or more translational members <NUM>.

Additionally, <FIG> illustrates that inner catheter <NUM> may include one or more tension resistance members 50a/50b. The tension resistance members 50a/50b may take the form of for example a wire (e.g., a metallic wire), a braid, cable, stranded cable, a composite structure. Further, <FIG> illustrates that tension resistance members 50a/50b may be positioned opposite one another on either side of lumen <NUM>.

Additionally, <FIG> shows guidewire member <NUM>. The guidewire member <NUM> may include a reinforcing coil <NUM> embedded with its tubular wall. For example, <FIG> shows coil <NUM> positioned with the wall of guidewire member <NUM>. Coil <NUM> may provide additional strength and flexibility to the guidewire member <NUM>. Additionally, <FIG> illustrates the lumen <NUM> of the guidewire member <NUM>.

<FIG> further illustrates the coupler <NUM> including the bottom surface <NUM> (described above). As illustrated, the bottom surface <NUM> is shaped to mate with the outer surface the guidewire member <NUM>. For example, in some examples, the bottom surface <NUM> may include a curved portion which mates with the radius defined by the outer surface <NUM> of the guidewire member <NUM>. As described above, the bottom surface <NUM> of the coupler <NUM> may or may not be rigidly fixed to the guidewire member <NUM>.

<FIG> illustrates a detailed view of a portion of the medical device system <NUM> shown in <FIG>. Further, <FIG> illustrates a cross-sectional view of coupler <NUM>. Coupler <NUM> may include a base member <NUM>, a first cap <NUM> and a second cap <NUM>. First cap <NUM> and second cap <NUM> may be separate components from base member <NUM>. Further, first cap <NUM> and second cap <NUM> may be attached to base member <NUM> via welding or any other suitable process.

As shown, a portion of the actuation rod <NUM> may extend into a portion of coupler <NUM> and thereby contact both base member <NUM> and first cap <NUM>. Similarly, portions of the translational members <NUM> may extend into a portion of coupler <NUM> and thereby contact both base member <NUM> and first cap <NUM>. It can be appreciated from <FIG> that base member <NUM> may include one or more projections <NUM> that mate with one or more recess <NUM> in the actuation rod <NUM>. Similarly, it can be appreciated from <FIG> that base member <NUM> may include one or more projections <NUM> that mate with one or more recesses <NUM> in the translational members <NUM>. It can further be appreciated that engaging a respective projection with a recess portion (in both the actuation rod <NUM> and the translational members <NUM>) may limit translational movement of both the actuation rod <NUM> and the translational members <NUM> relative to the coupler. In other words, engagement of a respective projection with a recess portion (in both the actuation rod <NUM> and the translational members <NUM>) may prevent both the actuation rod <NUM> and the translational members <NUM> from translating independently of the coupler <NUM> (and one another). However, it can be further appreciated that the engagement of a respective projection with a recess portion (in both the actuation rod <NUM> and the translational members <NUM>) may permit the actuation rod <NUM> to spin/swivel on its own longitudinal axis. Additionally, it can be appreciated that coupler <NUM> (including base member <NUM>, first cap <NUM> and second cap <NUM>) may permit dissimilar materials to be engaged because they are mechanically "trapped" and preferentially oriented within coupler <NUM>. In some instances, the coupler <NUM> may be defined as a "swivel.

It can be beneficial to have an indication of relative position of the actuation rod <NUM> (also referred to as a force translation rod), and thus an indication of the relative position of the coupler <NUM> and the translational members <NUM> (also referred to as push pull rods), as this can provide an indication of the relative position of the medical implant <NUM>. The present invention offers a variety of solutions to provide an indication of relative positions.

<FIG> shows a portion of a medical delivery device <NUM> in accordance with an aspect of the invention. It will be appreciated that some features and elements of the medical delivery device <NUM> may not be illustrated for clarity purposes. The medical delivery device <NUM> includes an inner rod <NUM> that is slidingly disposed within an outer sheath <NUM>. In some cases, the inner rod <NUM> may be considered as representing the actuation rod <NUM> and the outer sheath <NUM> may be considered as representing a portion of the inner catheter <NUM> discussed with respect to previous drawings. In some cases, the outer sheath <NUM> includes an electrically insulating layer. In some instances, the outer sheath <NUM> may represent or be a portion of the coil member <NUM> extending through the lumen <NUM>.

In accordance with this aspect of the invention, the inner rod <NUM> is formed of an electrically conductive material and is covered with an electrically insulating material. In some cases, the electrically insulating material may be a polymer such as Parylene or expanded polytetrafluoroethyene (better known as Teflon). One or more etched areas <NUM> are formed on the surface of the inner rod <NUM>. In some cases, the etched areas <NUM> may be formed by etching away the electrically insulating material. In some instances, while named etched areas <NUM>, the etched areas <NUM> may instead be formed by masking off these areas when coating the inner rod <NUM> with the electrically insulating material. These are just examples. In some cases, the inner rod <NUM> includes an etched area <NUM> at or near a proximal end <NUM> of the inner rod <NUM> so that electrical connection may be made to the inner rod <NUM>. In some instances, each of the etched areas <NUM> may be uniform in size and uniformly spaced apart. In some cases, the etched areas <NUM> may vary in length or width, and may vary in relative spacing in order to provide improved resolution, for example.

The outer sheath <NUM> includes a detection region <NUM> that is defined in part by a front seal <NUM> and a rear seal <NUM>. In some cases, the front seal <NUM> and/or the rear seal <NUM> may be O-rings, but this is not required in all cases. An internally exposed coil <NUM> is disposed relative to the detection region <NUM>. The outer sheath <NUM> also includes an externally exposed coil <NUM> that is electrically coupled to the internally exposed coil <NUM> via conductors <NUM>. It will be appreciated that the externally exposed coil <NUM> may provide a conductive path through the patient to an externally located electrode patch. In some instances, the externally exposed coil <NUM> may be used to couple to an external coil that inductively (for example) couples with the externally exposed coil <NUM> such that current flowing through the externally exposed coil <NUM> may cause a current to flow in the externally coupled coil. In some cases, a current may be applied to the inner rod <NUM>, which can be measured to determine the exposed area of the one or more etched areas <NUM>. In some cases, the internally exposed coil <NUM> and/or the externally exposed coil <NUM> may be coils that serve mechanical functions within the medical delivery device <NUM>.

<FIG> shows a portion of a medical delivery device <NUM> in accordance with another aspect of the invention. It will be appreciated that some features and elements of the medical delivery device <NUM> may not be illustrated for clarity purposes. The medical delivery device <NUM> includes an inner rod <NUM> that is slidingly disposed within an outer sheath <NUM>. In some cases, the inner rod <NUM> may be considered as representing the actuation rod <NUM> and the outer sheath <NUM> may be considered as representing a portion of the inner catheter <NUM> discussed with respect to previous drawings. In some cases, the outer sheath <NUM> includes an electrically insulating layer. In some instances, the outer sheath <NUM> may represent or be a portion of the coil member <NUM> extending through the lumen <NUM>.

As noted with respect to <FIG>, the inner rod <NUM> is formed of an electrically conductive material and is covered with an electrically insulating material. In some cases, the electrically insulating material may be a polymer such as Parylene or expanded polytetrafluoroethyene (better known as Teflon). One or more etched areas <NUM> are formed on the surface of the inner rod <NUM>. In some cases, the etched areas <NUM> may be formed by etching away the electrically insulating material. In some instances, while named etched areas <NUM>, the etched areas <NUM> may instead be formed by masking off these areas when coating the inner rod <NUM> with the electrically insulating material. These are just examples. In some cases, the inner rod <NUM> includes an etched area <NUM> at or near a proximal end <NUM> of the inner rod <NUM> so that electrical connection may be made to the inner rod <NUM>. In some cases, the etched area <NUM> is exposed in another manner, as long as the etched area <NUM> is electrically active.

In some instances, each of the etched areas <NUM> may be uniform in size and uniformly spaced apart. In some cases, the etched areas <NUM> may vary in length or width, and may vary in relative spacing in order to provide improved resolution, for example. This can be seen in <FIG> and <FIG>. <FIG> shows an inner rod 82a that includes a number of etched areas 86a that each extend at least partially radially around the inner rod 82a. While each of the etched areas 86a are roughly the same size, it can be seen that the relative spacing between adjacent etched areas 86a varies over the length of the inner rod 82a. <FIG> shows an inner rod 82b that includes a number of etched areas that each extend at least partially radially around the inner rod 82b. While the relative spacing between adjacent etched areas remains roughly constant, the size of each etched area varies. For example, an etched area 86b is larger than an etched area 86c, which in turn is larger than an etched area 86d, and so on.

Returning to <FIG>, the outer sheath <NUM> includes in accordance with this aspect of the invention a resilient switch <NUM> that is configured to make contact with the etched areas <NUM> on the inner rod <NUM> (or 82a or 82b, for example). As best seen in <FIG>, which is a cross-sectional view along line <NUM>-<NUM> of <FIG>, the resilient switch <NUM> is configured to make electrical contact with the etched areas <NUM> as the inner rod <NUM> translates relative to the resilient switch <NUM>. The resilient switch <NUM> includes one or more electrical connections <NUM> that are electrically coupled with the resilient switch <NUM> and extend towards the handle <NUM> (<FIG>).

In accordance with another aspect of the invention, a magnetic switch is used. <FIG> is a cross-sectional view of a portion of a medical delivery device <NUM> which is similar to the cross-sectional view shown in <FIG>, although the inner shaft includes several longitudinally extending slots <NUM> formed on an outer surface of the inner shaft. In some cases, these longitudinally extending slots <NUM> may be used to convey wires from a position sensor as described in <FIG>. In some cases, as illustrated, a magnetic switch <NUM> may be disposed in one of the longitudinally extending slots <NUM>. In accordance with this aspect of the invention, magnetic switch <NUM> is sensitive to ferromagnetic segments <NUM>, which as shown in <FIG> can be spaced, equally or variably, along the inner rod <NUM>. As can be seen in <FIG>, which provides a plot of sensor output (in volts) versus displacement (in millimeters), a magnetic switch can provide an easily seen indication of position, as a good signal can be obtained. The plot includes a line <NUM> having a peak <NUM> that provides a strong signal. In some cases, a reed switch may be used. In some cases, a Hall effect sensor may be used.

The materials that can be used for the various components of the medical devices and/or system <NUM> disclosed herein may include those commonly associated with medical devices. However, this is not intended to limit the devices and methods described herein, as the discussion may be applied to other components of the medical devices and/or systems <NUM> disclosed herein including the various shafts, liners, components described relative thereto.

The medical device <NUM> may be made from a metal, metal alloy, polymer (some examples of which are disclosed below), a metal-polymer composite, ceramics, combinations thereof 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. 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), nickel-copper alloys (e.g., UNS: N04400 such as MONEL® <NUM>, NICKELVAC® <NUM>, NICORROS® <NUM>), nickel-cobalt-chromium-molybdenum alloys (e.g., UNS: R30035 such as MP35-N®), 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; cobalt-chromium alloys; cobalt-chromium-molybdenum alloys (e.g., UNS: R30003 such as ELGILOY®, PHYNOX®); platinum enriched stainless steel; titanium; combinations thereof, or any other suitable material.

In at least some embodiments, portions or all of the medical device <NUM> 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 medical device <NUM> in determining its location. Some examples of radiopaque materials can include for example gold, platinum, palladium, tantalum, tungsten alloy, and polymer material loaded with a radiopaque filler. Additionally, other radiopaque marker bands and/or coils may also be incorporated into the design of the medical device <NUM> to achieve the same result.

In some embodiments, a degree of Magnetic Resonance Imaging (MRI) compatibility is imparted into the medical device <NUM>. For example, the medical device <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 medical device <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®), nickel-cobalt-chromium-molybdenum alloys (e.g., UNS: R30035 such as MP35-N®), nitinol and others.

Claim 1:
A delivery system for delivering an implantable medical device (<NUM>) to a portion of the cardiovascular system, comprising:
an outer shaft (<NUM>) defining an outer shaft lumen;
an inner shaft (<NUM>, <NUM>) translatable within the outer shaft lumen;
the inner shaft (<NUM>, <NUM>) defining a lumen (<NUM>) extending through the inner shaft (<NUM>); an actuation mechanism extending through the lumen (<NUM>), the actuation mechanism including a coupler (<NUM>), a force translation rod (<NUM>, <NUM>) that extends proximally from the coupler (<NUM>) and a plurality of push pull rods (<NUM>) that extend distally from the coupler (<NUM>) and that releasably couple to the implantable medical device (<NUM>); characterized by
an internally exposed coil (<NUM>) disposed within the inner shaft (<NUM>, <NUM>) and electrically coupled to an externally exposed coil (<NUM>) that can be used to conductively transmit a current flowing through the internally exposed coil (<NUM>);
the force translation rod (<NUM>, <NUM>) formed of an electrically conducting material with an electrically insulating outer layer, with one or more etched areas (<NUM>) extending through the electrically insulating outer layer, wherein when the force translation rod (<NUM>, <NUM>) moves relative to the inner shaft (<NUM>, <NUM>), and thus the one or more etched areas (<NUM>) move relative to the internally exposed coil (<NUM>, <NUM>), an impedance varies in accordance with relative position.