Patent Description:
Some applications of the present invention relate in general to transluminal implant-delivery systems. More specifically, the present invention relates to apparatus for use at a heart of a subject, the apparatus comprising a delivery tool and a prosthetic heart valve.

Dilation of the annulus of a heart valve, such as that caused by ischemic heart disease, prevents the valve leaflets from fully coapting when the valve is closed. Regurgitation of blood from the ventricle into the atrium results in increased total stroke volume and decreased cardiac output, and ultimate weakening of the ventricle secondary to a volume overload and a pressure overload of the atrium.

<CIT> relates to a system and method of stepped deployment of a prosthetic heart valve, and discloses apparatus according to the pre-amble of appended independent claim <NUM>.

<CIT> relates to hydraulic delivery systems for prosthetic heart valve devices and associated methods.

<CIT> relates to a transcatheter prosthetic heart valve delivery device with stability tube.

In accordance with the present invention, there is provided apparatus for use in a heart of a subject as defined in appended independent claim <NUM>. Embodiments of the present invention are defined in appended claims dependent on independent claim <NUM>. Methods of using the apparatus are described to help understand the present invention and do not form part of the present invention.

Applications of the present disclosure are directed to apparatus and methods for delivering an implant to a subject.

For some applications, aspects of the present disclosure include a transluminal delivery tool that includes a multi-catheter system and an implantation instrument. The implantation instrument has a distal part that is configured to be advanced into the subject, as well as a proximal part that includes an extracorporeal control system.

The catheter system typically includes a first catheter unit and a second catheter unit, each catheter unit including a respective catheter that is mounted at a proximal end thereof to a respective handle. Selective adjustment of the axial and/or rotational position of each handle facilitates adjustment of the axial and/or rotational position of the corresponding catheter. Typically, the respective handles, and the proximal portion of the implantation instrument, are mounted on a mount for stabilization during use.

For some applications, a first catheter extends distally from within a second catheter. For some such applications, sliding a first-catheter distal portion distally over a second-catheter distal portion, ensheathes the second-catheter distal portion within the first-catheter distal portion, and sliding the first-catheter distal portion proximally over the second-catheter distal portion exposes the second-catheter distal portion from the first catheter.

Typically for such applications, actuation of a first-catheter controller actively bends the first-catheter distal portion via a first-catheter control element, and actuation of a second-controller controller actively bends a second-catheter distal portion via a second-catheter control element.

For some applications, each control element includes a pull wire that extends from a respective controller, through a secondary lumen of the respective catheter, to a distal portion of the catheter, to which the pull wire is fixed.

For some applications, each catheter (e.g., a distal end thereof) is bendable, by actuation of the respective controller, along a respective steering plane. For some such applications, the second catheter is rotationally oriented with respect to the first catheter such that, while the first-catheter distal end is bent in a first-catheter steering plane, bending of the second-catheter distal end causes the second-catheter distal end to rotate with respect to the first-catheter distal end such that the second-catheter steering plane moves toward being perpendicular to the fist-catheter steering plane.

For some applications, a distal part of the second catheter is coupled to a capsule assembly. For some such applications, the capsule assembly includes a proximal capsule and a distal capsule. For example, each capsule may have a respective open end that faces the open end of the other capsule.

For some applications, the distal part of the delivery tool includes a plurality of coaxial tubular members that extend distally from the proximal portion of the instrument (e.g., through the second catheter of the catheter system). Typically for such applications, a capsule catheter extends distally through the second catheter and out an open distal end of the second catheter. Further typically for such applications, a shaft extends distally from the proximal portion of the delivery tool, through the capsule catheter and out of the open end of the proximal capsule. For example, a mount (e.g., to which the implant may be engaged) may be fixedly coupled to a distal end of the shaft.

For some such applications, a rod extends out of a distal end of the shaft, such that a distal portion of the rod is disposed outside of the distal end of the shaft. Typically for such applications, the rod is operatively coupled to the shaft such that the rod may be screwed through the shaft.

Typically, the implant may be ensheathed (e.g., restrained from expanding) within the capsule assembly. For some applications, the implant comprises a proximal-implant portion, a distal-implant portion and a flange. Typically for such applications, the implant is ensheathed during delivery of the delivery tool such that the proximal-implant portion and at least a flange end-portion of the flange are restrained within the proximal capsule. Further typically for such applications, the distal-implant portion of the implant is restrained within the distal capsule.

For some applications, the implant may be unsheathed from the distal capsule by moving the distal capsule linearly off of the implant (e.g., without screwing the distal capsule with respect to the rod). For some such applications, the distal capsule is rotationally coupled to the distal portion of the rod, such that rotation of the rod does not rotate the distal capsule. For example, the distal capsule may be advanced distally off of the implant by screwing the rod through the shaft while the distal capsule is axially locked with respect to the rod, yet rotationally coupled to the rod.

For some such applications, the capsule assembly includes a plurality of pins that are axially aligned with a circumferential recess defined by the rod. Typically for such applications, the pins inhibit rotation of the distal capsule by traversing the distal capsule sufficiently closely to the rod to inhibit axial movement of the rod with respect to the pins, while providing sufficient clearance between the pins and the rod (e.g., the recess defined thereby) to allow the rod to rotate with respect to the pins.

For some applications, the distal capsule is reversibly rotationally lockable or unlockable with respect to the rod, such that the implant may be ensheathed in the distal capsule by moving the distal capsule helically over the implant, and unsheathed by moving the distal capsule linearly off of the implant. For example, an accessory may be introduced (e.g., defining a detent shaped to fit into the recess defined by the rod and the distal capsule) configured to rotationally lock the rod with respect to the distal capsule. In this way, the accessory may be attached for ensheathing of the implant within the distal capsule, and the accessory subsequently removed before unsheathing (e.g., before transluminal delivery) of the implant.

Aspects of the present invention include apparatus that comprises a delivery tool and the prosthetic valve. For some such applications, the delivery tool is configured to deliver the prosthetic valve to a native valve of a heart of the subject. For example, the native valve may be a tricuspid valve.

The delivery tool has a proximal portion and a distal portion. The distal portion comprises a proximal capsule and a distal capsule, each of the capsules defining a respective open end.

The open end of the proximal capsule faces the proximal end of the distal capsule. The open end of the proximal capsule may face the open end of the distal capsule. For example, while the delivery tool is in a delivery state for transluminally delivering the delivery tool to the heart, an inter-capsule gap may separate between the open end of the proximal capsule and the open end of the distal capsule.

The prosthetic valve comprises a tubular portion that defines a lumen, within which a plurality of prosthetic leaflets are disposed. Typically for such applications, the prosthetic valve further comprises an upstream support portion that extends from the tubular portion, and defines a plurality of flanges. Each flange is coupled to the tubular portion at a coupling point, from which the flange extends to flange end-portion.

While the delivery tool is in the delivery state, the prosthetic valve is restrained in a compressed state by the delivery tool. For some such applications, while the delivery tool is in the delivery state, the tubular portion of the prosthetic valve is engaged with a mount of the delivery tool. Alternatively or in addition, the prosthetic valve may be engaged with a portion of the shaft, mutatis mutandis.

For some applications, while the delivery tool is in the delivery state, the mount and a downstream end of the tubular portion are disposed within the distal capsule, and the upstream support portion and the flange end-portions are disposed within the proximal capsule. Further typically, while the delivery tool is in the delivery state, a segment of the tubular portion is disposed at the inter-capsule gap.

For some applications, the delivery tool is transluminally advanced to a ventricle of the heart, such that the distal capsule is disposed within the ventricle. For some such applications, the delivery tool comprises a flexible sheath, and the sheath is retracted, exposing the proximal capsule from the sheath.

For some applications, the delivery system comprises a guidewire along which the delivery tool is transluminally advanced to the heart. For some such applications, the delivery tool comprises a nosecone having a flexible distal end-portion. For example, the distal end-portion may have a relaxed curled shape, and the distal end-portion may be straightened when the guidewire occupies the distal end-portion.

For some applications, the delivery tool comprises a shaft that comprises a rigid proximal shaft segment that extends from the proximal portion of the delivery tool to the distal portion of the delivery tool. For some such applications, the shaft comprises a flexible shaft segment that extends from the rigid proximal shaft segment to a rigid distal shaft segment. Typically for such applications, the rigid distal shaft segment extends through at least part of the proximal capsule and/or of the distal capsule.

Typically, the proximal capsule is then proximally retracted, such that the flange end-portions are released from the proximal capsule and expand radially outward. For some applications, the delivery tool comprises a disc-assembly comprising a proximal disc that is rotatably coupled to a distal disc. The proximal disc defines outer threading that is complementary to inner threading defined by the proximal capsule. Typically for such applications, rotation of a capsule catheter that is fixedly coupled to the proximal disc, screws the proximal capsule over the disc-assembly, with respect to the mount.

Further typically, the distal portion is then retracted, such that the flange end-portions contact tissue of the native valve. The proximal capsule is then retracted, such that the upstream support portion is released from the proximal capsule, and expands radially outward. In this way, tissue of the native valve is squeezed between the upstream support portion and the flange end-portions.

Subsequently, the distal capsule is advanced with respect to the mount, thereby releasing the mount and the downstream end of the tubular portion from the distal capsule. Thus, the tubular portion expands radially outward at the native valve, such that the prosthetic valve assumes an expanded state.

Subsequently, the proximal capsule is advanced toward the mount, such that the open end of the proximal capsule abuts the distal capsule. For some applications, the open end of the proximal capsule abuts the open end of the distal capsule. For some applications, the distal capsule is retracted toward the mount, prior to advancing the proximal capsule. While the proximal capsule abuts the distal capsule, the distal portion of the delivery tool is retracted through the lumen of the tubular portion.

Reference is made to <FIG>, which are schematic illustrations of a delivery tool <NUM>.

As shown in <FIG>, delivery tool <NUM> is a multi-catheter transluminal (e.g., transfemoral) delivery tool, comprising two primary components: a catheter system <NUM>, and an implantation instrument <NUM>.

Catheter system <NUM> comprises a first catheter unit <NUM> that comprises a first catheter (e.g., an outer catheter) <NUM> coupled at a proximal end thereof to a first-catheter handle <NUM>; and a second catheter unit <NUM> that comprises a second catheter <NUM> coupled at a proximal end thereof to a second-catheter handle <NUM>. A proximal opening of second catheter <NUM> is accessible proximally from first catheter <NUM>, and the second catheter extends distally through the lumen of first catheter <NUM>, and out of a distal end of the first catheter. Typically, second-catheter handle <NUM> is disposed proximally from first-catheter handle <NUM>. Typically, handles <NUM> and <NUM> are mounted on a mount <NUM> to stabilize the handles during use. Further typically, the handles are mounted in a manner that facilitates selective adjustment of the axial and/or rotational position of the handles, and therefore their corresponding catheters.

Typically, each of catheters <NUM> and <NUM> is steerable, and this steerability is controlled by respective controllers <NUM>, <NUM> (which may be alternatively referred to as bend-actuators) of the respective catheter unit, each of the controllers being operably coupled to a steerable distal end-portion of its respective catheter via one or more bend-control elements, such as pull-wires, that extend along and within the respective catheter. This is described in more detail hereinbelow. It is to be noted that the term steerable (including the specification and the claims) means actively steerable (e.g., by an extracorporeal control system), not merely sufficiently flexible to be bent responsively when pressed against a surface. Controllers <NUM> and <NUM> are typically mounted on the respective handle of their respective catheter unit. As shown, controllers <NUM> and <NUM> may be rotatable controllers such as wheels.

Implantation instrument <NUM> (<FIG> and <FIG>) has a proximal portion <NUM> that is typically disposed proximally from handles <NUM> and <NUM>, and that is typically also mounted on mount <NUM>. Handle <NUM>, handle <NUM>, and proximal portion <NUM> are disposed at a proximal part <NUM> of delivery tool <NUM> that is configured to remain outside the subject during use. Proximal part <NUM> may be considered to be an extracorporeal control system. A distal part <NUM> of delivery tool <NUM> (e.g., a distal portion <NUM> of implantation instrument <NUM>) is configured to be advanced into the subject, and comprises a capsule assembly <NUM> that houses implant <NUM> during this advancement.

Instrument <NUM> comprises a plurality of tubular members that extend distally from proximal portion <NUM>, which are coaxial about a central longitudinal axis ax1 of delivery tool <NUM>, and which are discussed in more detail hereinbelow. The outermost of these tubular members is typically a capsule catheter <NUM> that extends distally from proximal portion <NUM>, through catheter <NUM>, out of an open distal end of catheter <NUM>, to distal part <NUM>, where it abuts, and/or is coupled to a proximal capsule <NUM> of capsule assembly <NUM> (<FIG>). Proximal capsule <NUM> comprises a circumferential wall that extends distally from capsule catheter <NUM> to define a chamber of the proximal capsule. Capsule assembly <NUM> further comprises a distal capsule <NUM>. Each of capsules <NUM> and <NUM> has a respective open end that faces the open end of the other capsule (see description hereinbelow of open ends <NUM> and <NUM> with reference to <FIG>).

As shown in the cross-sectional view shown in the upper inset of <FIG>, the tubular members of instrument <NUM> include a shaft <NUM> that extends distally from proximal portion <NUM>, coaxially through capsule catheter <NUM>. As shown in <FIG>, shaft <NUM> typically extends through proximal capsule <NUM>, and out of the open end of the proximal capsule.

As described hereinbelow (e.g., with reference to <FIG>), for delivery of implant <NUM>, the implant is housed, compressed around shaft <NUM>, within capsule assembly <NUM>. For some applications, a mount <NUM> (<FIG>, <FIG>) to which the implant may be engaged, is fixedly coupled to a distal end of shaft <NUM>. Alternatively or in addition to the mount engaging the implant, the implant may be engaged with a portion of the shaft, mutatis mutandis.

Typically, a downstream portion (e.g., downstream end <NUM> of prosthetic valve <NUM> described hereinbelow with reference to frame A of <FIG>) of an implant is disposed within distal capsule <NUM> and engaged with mount <NUM> (e.g., implant-engaging slots <NUM> thereof), and an upstream portion (e.g., upstream end <NUM> of the prosthetic valve described with reference to frame A of <FIG>) of the implant is disposed within proximal capsule <NUM>.

A rod <NUM> (upper inset of <FIG>) is disposed coaxially through shaft <NUM>. Rod <NUM> may define a guidewire lumen therethrough, and may therefore be another of the tubular members of instrument <NUM>. Rod <NUM> extends out of the distal end of shaft <NUM> (<FIG>), such that a distal portion of the rod is disposed outside of the distal end of the shaft. Rod <NUM> is operatively coupled to shaft <NUM> such that rotational movement of the rod with respect to the shaft is converted into axial movement (e.g., along longitudinal axis ax1) of the rod with respect to the shaft. This is typically achieved by shaft <NUM> defining an internal screw thread, and rod <NUM> defining a complementary external screw thread <NUM> (<FIG>).

For some applications, and as shown, shaft <NUM> has a rigid distal portion 164d within which the internal screw thread is defined. For such applications, more proximal portions of shaft <NUM> (indicated by reference numeral 164p in <FIG>) are flexible. Despite the difference in flexibility of portions 164p and 164d, these portions are typically axially and rotationally locked, and define a continuous lumen throughout the entirety of shaft <NUM>.

Distal capsule <NUM> is coupled to the distal portion of rod <NUM>, and comprises a circumferential wall that extends proximally from the distal portion of the rod to define a chamber of the distal capsule. Distal capsule <NUM> is typically axially locked with respect to rod <NUM>, meaning that axial movement of the rod distally or proximally moves the distal capsule axially distally or proximally. However, distal capsule <NUM> is rotationally coupled to and rotationally movable with respect to rod <NUM>, meaning that rotation of the rod does not necessarily rotate the distal capsule (e.g., if the distal capsule encounters rotational resistance). It is hypothesized by the inventors that this advantageously facilitates generally axial distal sliding of distal capsule <NUM> off of an implant that is disposed within distal capsule <NUM> (e.g., rather than the sliding off requiring helical rotation of the distal capsule with respect to the implant, which might increase an amount of abrasion between the distal capsule and the implant).

For some applications, and as shown in the lower inset of <FIG>, this axial locking and rotational coupling is provided by pins <NUM> that extend transversely through distal capsule <NUM>, laterally from rod <NUM>. Pins <NUM> are typically disposed distally from the chamber of the distal capsule. Pins <NUM> are typically axially aligned with a circumferential recess <NUM> defined in rod <NUM>, such that the pins are sufficiently close to the rod to inhibit axial movement of the rod with respect to the pins, while providing sufficient clearance between the pins and the rod (e.g., recess <NUM>) to allow the rod to rotate with respect to the pins.

Reference is made to <FIG>, <FIG>, <FIG>, <FIG>, which are schematic illustrations showing delivery tool <NUM> in various states thereof for use with an implant <NUM>.

<FIG> show capsule assembly <NUM> of delivery tool <NUM> in various states thereof. <FIG> show delivery tool <NUM> being used to deliver implant <NUM>, and being transitioned between the various states in order to implant the implant. Implant <NUM> is described herein as being a prosthetic valve, but for some applications may be a different implant. For some applications, implant <NUM> is a prosthetic valve <NUM> described hereinbelow, and/or may be identical to implant (prosthetic valve) <NUM> of <CIT>. Implant <NUM> is typically self-expanding.

<FIG> shows distal portion <NUM> of instrument <NUM> (e.g., capsule assembly <NUM> thereof) in a closed state thereof. In this state, and with implant <NUM> disposed within capsule assembly <NUM>, the capsule assembly is advanced transluminally (e.g., transfemorally) to a native valve <NUM> of the heart <NUM> of a subject (<FIG>). Although <FIG> show native valve <NUM> as the mitral valve, delivery tool <NUM> may alternatively be used to deliver an implant (e.g., a prosthetic valve) to another native valve of the heart, such as the tricuspid valve, the aortic valve, or the pulmonary valve, mutatis mutandis.

For some applications, and as shown in <FIG>, during transluminal advancement of delivery tool <NUM>, capsule assembly <NUM> may be retracted proximally so as to abut the distal open end of second catheter <NUM>, and/or the distal open end of first catheter <NUM>. <FIG> shows delivery tool <NUM> being advanced in this manner, with catheter <NUM> and capsule catheter <NUM> hidden inside catheter <NUM>. Once within atrium <NUM>, upstream of native valve <NUM> (in this case the left atrium, upstream of the mitral valve), catheter <NUM> is extended from catheter <NUM> (<FIG>), and is steered to point capsule assembly <NUM> toward and through the native valve.

For some applications, extension of catheter <NUM> from catheter <NUM> (e.g., by sliding catheter <NUM> with respect to catheter <NUM>) is actuated using a juxtaposition actuator <NUM> (<FIG> and <FIG>). For some such applications, catheter <NUM> is extended from catheter <NUM> while the catheters are rotationally locked with respect to each other. For example, catheters <NUM>, <NUM> may be rotationally locked via a proximal lock defined by actuator <NUM>. Alternatively or in addition, a distal lock defined by respective couplings of catheters <NUM>, <NUM> may rotationally lock catheters <NUM>, <NUM> with respect to each other. For example, the couplings defining the distal lock may be in certain ways similar to those described in <CIT> (e.g., with reference to <FIG> thereof).

For some applications, and as shown in <FIG>, after the initial positioning of capsule assembly <NUM> (<FIG>), catheters <NUM> and <NUM> remain stationary throughout subsequent manipulation of the capsule assembly. For such applications, advancement and retraction of capsule catheter <NUM> from and into catheter <NUM> facilitates advancement and retraction of capsule assembly <NUM> as a whole, and of proximal capsule <NUM>, independently of distal capsule <NUM>.

Subsequently, and as shown in <FIG> and <FIG>, distal capsule <NUM> is advanced distally, in order to release flanges <NUM> of implant <NUM>, allowing the flanges to automatically expand radially outward. It is to be noted that the upstream end of implant <NUM> remains within proximal capsule <NUM>, and mount <NUM> and the downstream end of the implant remain within distal capsule <NUM> at this stage. Because mount <NUM> is fixedly coupled to shaft <NUM>, and distal capsule <NUM> is axially locked with respect to rod <NUM>, this distal advancement of distal capsule <NUM> off of implant <NUM> can be achieved by distally advancing the rod with respect to the shaft (e.g., by screwing the rod through the shaft).

For some applications, and as shown, this step of deploying flanges <NUM> is performed while the flanges (and the seam between capsules <NUM> and <NUM>) are disposed within atrium <NUM>. For such applications, while the deployment state of capsule assembly <NUM> typically remains as shown in <FIG>, the capsule assembly is subsequently advanced distally, downstream through native valve <NUM> (<FIG>), until it is determined via imaging (e.g., fluoroscopy) that the leaflets <NUM> of the native valve are coapting upstream of flanges <NUM> during ventricular systole (<FIG>). This is hypothesized by the inventors to facilitate reliable placement of the flanges downstream of the leaflets, while minimizing the distance downstream of the leaflets that the deployed flanges are advanced, thereby advantageously reducing a likelihood of inadvertently ensnaring ventricular tissue such as chordae tendineae.

Subsequently, and while the deployment state of capsule assembly <NUM> typically remains as shown in <FIG>, the capsule assembly is retracted proximally, upstream, until it is determined (e.g., via imaging, such as fluoroscopy) that flanges <NUM> have engaged leaflets <NUM> (<FIG>).

Subsequently, as shown in <FIG>, an upstream support portion <NUM> of implant <NUM> is deployed by releasing it from proximal capsule <NUM>, by retracting the proximal capsule proximally with respect to mount <NUM> (and therefore with respect to the implant) (<FIG>). This may be achieved by moving capsule catheter <NUM> proximally (as shown), or may be achieved by rotating the capsule catheter (e.g., as described hereinbelow for delivery tool <NUM>, mutatis mutandis). Upstream support portion <NUM> typically comprises a plurality of radial arms, and optionally a flexible sheet covering the arms, and becomes disposed over the upstream surface of the annulus of native valve <NUM> (<FIG>). Leaflets <NUM> therefore become at least lightly sandwiched between upstream support portion <NUM> and flanges <NUM>.

Subsequently, as shown in <FIG>, implant <NUM> is fully deployed by releasing the distal end of the implant from distal capsule <NUM>, by advancing the distal capsule distally with respect to mount <NUM> (<FIG>). That is, mount <NUM> is typically shaped to engage the distal end of the implant (e.g., by slots <NUM> defined by the mount receiving adaptors <NUM> defined by the distal end of the implant, as described hereinbelow with reference to <FIG>), such that exposing the mount from the distal capsule fully releases the implant from the distal capsule.

For some such applications, distal advancement of distal capsule <NUM> is accomplished via axial movement of rod <NUM>. Typically for such applications, the axial movement of the rod transitions delivery tool <NUM> from a retracted state (<FIG>), in which a part of shaft <NUM> and/or implant-receiving slots <NUM> are within distal capsule <NUM>, to an extended state (<FIG>), in which the part of the shaft and/or the slots are outside the distal capsule.

As shown in <FIG>, expansion of implant <NUM> opens a central channel of the implant to blood flow, and allows leaflets of the implant (not shown) to provide one-way valve functionality. The expansion also typically further squeezes leaflets <NUM> between upstream support portion <NUM> and flanges <NUM>, thereby securing implant <NUM> in place, and inhibiting paravalvular leakage.

<FIG>, <FIG> show respective views of distal part <NUM> of delivery tool <NUM>, at the stage of deployment shown in <FIG>, but with certain differences as noted, in order to illustrate some flexibility that delivery tool <NUM> provides, and which the inventors hypothesize to be advantageous. In both <FIG> and <FIG>, catheter <NUM> extends through fossa ovalis <NUM> into atrium <NUM>, and is steered toward a position that is overhead of valve <NUM> (e.g., overhead of the center of valve <NUM>). Also, in both <FIG> and <FIG>, catheter <NUM> extends out of catheter <NUM>, and is steered downward toward valve <NUM>, such that capsule assembly <NUM> is disposed between leaflets <NUM> of the valve. However, in contrast to <FIG>, the cardiac anatomy in the example shown in <FIG>is such that, in order to position capsule assembly <NUM> between the leaflets, the capsule assembly has been advanced away from catheter <NUM> and no longer abuts the catheter. This may be advantageous, for example, if fossa ovalis <NUM> is particularly high above native valve <NUM>. In contrast to <FIG>, the cardiac anatomy in the example shown in <FIG> is such that, in order to position capsule assembly <NUM> between the leaflets, additional steering is desirable. In the example shown in <FIG>, the cardiac anatomy is such that the distance between fossa ovalis <NUM> and native valve <NUM> is shorter than that in <FIG>, and the cumulative length of the steerable distal portion of catheter <NUM> and the steerable distal portion of catheter <NUM> would be too great to obtain the desired angle of attack.

<FIG> illustrate an additional steering feature that, for some applications, is included in delivery tool <NUM>. This steering feature is the steerability of shaft <NUM> (or at least a steerable distal region of proximal portion 164p (<FIG>)). It is hypothesized that this steering feature advantageously increases the flexibility of delivery tool <NUM>, and its suitability to a greater range of anatomies.

As shown in the upper inset of <FIG>, steerability of shaft <NUM> is provided by pull-wires 364a and 364b that extend from the steerable distal region of the shaft, proximally within the shaft to a controller <NUM> of proximal portion <NUM> of implantation instrument <NUM>, similarly to the steerability of catheters <NUM> and <NUM>, mutatis mutandis. This is described in more detail hereinbelow.

In the example shown in <FIG>, steering of shaft <NUM> is used in addition to steering of catheter <NUM>. In the example shown in <FIG>, steering of shaft <NUM> is used instead of steering of catheter <NUM>, with catheter <NUM> barely exposed from catheter <NUM>. It is to be noted that, as shown, while shaft <NUM> is steerable (meaning actively steerable), it is disposed within catheter <NUM>, which is flexible (but not itself steerable) and therefore passively bends in response to the steering of shaft <NUM>.

Reference is again made to <FIG>, which includes a cross-section of delivery tool <NUM> that illustrates the arrangement of the various tubular members and pull-wires thereof. Two pull-wires 322a and 322b extend proximally from a steerable distal portion of catheter <NUM> to controller <NUM>, actuation of which steers the steerable portion of catheter <NUM>. Two pull-wires 332a and 332b extend proximally from a steerable distal portion of catheter <NUM> to controller <NUM>, actuation of which steers the steerable portion of catheter <NUM>. For applications in which shaft <NUM> is steerable, two pull-wires 364a and 364b extend proximally from a steerable portion of shaft <NUM> to controller <NUM> (e.g., a shaft bend-actuator thereof), actuation of which steers the steerable portion of shaft <NUM>.

Reference is made to <FIG>, which is a schematic illustration showing, in frames A and B thereof, a two-catheter system <NUM>', as is known in the prior art. Elements of two-catheter system <NUM>' are labeled with the same reference numerals as corresponding elements of catheter system <NUM>, with the addition of an apostrophe: '. As shown, pull-wire plane p3' passes through both pull-wires 332a' and 332b' of inner catheter <NUM>', and is rotationally offset with respect to pull-wire plane p2' that passes through both pull-wires 322a' and 322b' of outer catheter <NUM>'.

Typically, pull-wire planes p2' and p3' define respective steering planes along which catheters <NUM>', <NUM>' can be bent, and therefore, along which catheter system <NUM>' can be steered. Outer catheter <NUM>' and inner catheter <NUM>' are typically rotationally oriented with respect to each other such that pull-wire planes p2' and p3' are offset by a <NUM>-degree angle_1' (frame A of <FIG>).

As shown in frame B of <FIG>, tensioning of pull-wire 322b' of outer catheter <NUM>' may not significantly alter the rotational orientation of inner catheter <NUM>' with respect to the outer catheter. That is, while catheter system <NUM>' is steered along pull-wire plane p2' of outer catheter <NUM>', both the outer catheter and inner catheter <NUM>' may bend along pull-wire plane p2', such that angle alpha_1' is maintained at <NUM> degrees.

Reference is made to frame C of <FIG>, which shows a hypothetical state of two-catheter system <NUM>'. As shown, when inner catheter <NUM>' is steered along a steering plane that is different from plane p2', bending of the inner catheter may yield rotational slippage of the inner catheter with respect to the outer catheter (rotational arrows). Thus, steering of inner catheter <NUM>' within bent outer catheter <NUM>' may cause pull-wire planes p2' and p3' to become closer to being co-planar, such that alpha_1' deviates from <NUM> degrees (e.g., becomes acute in frame C). This rotational slippage may therefore reduce the range of steering of catheter system <NUM>' and/or not yield the desired final steering angle of inner catheter <NUM>'.

It is therefore hypothesized by the inventors that an improved placement of the pull-wires (when the catheter system is at rest) to address this issue is not at a <NUM>-degree offset.

Reference is made to <FIG>, which is a schematic illustration showing catheter system <NUM>. In catheter system <NUM>, the pull-wires are positioned such that, at rest (e.g., with no steering or bending of the catheters), pull-wire planes p2 and p3 are not offset by <NUM> degrees. For example, and as shown in frame A, an obtuse angle alpha_1 formed by the intersection of plane p3 and plane p2 may be greater than <NUM> degrees and/or less than <NUM> degrees (such as about <NUM> degrees). For some applications in which catheters <NUM>, <NUM> are rotationally lockable via a proximal lock and/or a distal lock, as described hereinabove with reference to <FIG>, the proximal and/or distal locks may keep pull-wire planes p2 and p3 offset such that angle alpha_1 remains obtuse along a length of the catheters.

Tensioning of pull-wire 322b of first catheter <NUM> may not significantly alter the rotational orientation of second catheter <NUM> with respect to the first catheter. That is, while catheter system <NUM> is steered along pull-wire plane p2 of first catheter <NUM>, both the first catheter and second catheter <NUM> may bend along pull-wire plane p2, such that angle alpha_1 is maintained as an obtuse angle.

However, because angle alpha_1 is obtuse when catheter system <NUM> is at rest, rotational slippage of second catheter <NUM> with respect to first catheter <NUM> (rotational arrows in frame C of <FIG>) resulting from steering the second catheter <NUM> along plane p3 brings angle alpha_1 closer to <NUM> degrees, thereby improving the ease of steering of catheter system <NUM>, relative to catheter system <NUM>'. For some applications in which catheters <NUM>, <NUM> are rotationally lockable via a proximal lock and/or a distal lock, the proximal and/or distal locks may be unlocked prior to steering the second catheter <NUM> along plane p3, thereby allowing at least a portion of the second catheter to rotate with respect to the first catheter, such that plane p3 moves toward being perpendicular to plane p2.

It is therefore hypothesized by the inventors that positioning pull-wires 322a, 322b, 332a, 332b such that, while at rest, pull-wire planes p2 and p3 are not offset by <NUM> degrees, facilitates bi-planar steering of catheter system <NUM>. Even if rotational slippage in catheter system <NUM> continues past the <NUM>-degree position, such that angle alpha_1 becomes less than <NUM> degrees, this resulting angle is advantageously greater than that of steering system <NUM>', in which the initial angle is <NUM> degrees.

Reference is now made to <FIG> and <FIG>, which are schematic illustrations showing at least some steps of loading implant <NUM> into capsule assembly <NUM> of delivery tool <NUM>. It is hypothesized by the inventors that it is advantageous to load implant <NUM> into distal capsule <NUM> in at least two steps. In a first step (<FIG>), the implant is slid proximally over distal capsule <NUM>. In a second step (<FIG>), distal capsule <NUM> is slid over the implant by manipulating the distal capsule from distal part <NUM> of delivery tool <NUM> (as described hereinbelow), rather than from proximal part <NUM> of the delivery tool. That is, whereas an unsheathing force applied by the operator during deployment of implant <NUM> is applied to actuator <NUM> of proximal portion <NUM> as described hereinabove (e.g., <FIG>), it is hypothesized by the inventors that it is advantageous to apply the ensheathing force directly to distal part <NUM>, e.g., such that greater force can be applied to the implant, and/or such that the application of the ensheathing force is performed near to the site of manipulation of implant <NUM>, thereby improving visibility of the implant to the person performing the ensheathing and/or improving control of the loading process.

For some applications, and as shown in <FIG>, actuator <NUM> (visible in <FIG> and <FIG>) is entirely removed from instrument <NUM>, prior to ensheathing implant <NUM> in distal capsule <NUM>. (Alternatively, instrument <NUM> may be provided with actuator <NUM> initially separate from the rest of the instrument.

As described hereinabove, distal capsule <NUM> is rotationally coupled to rod <NUM> (<FIG> and <FIG>). Therefore, rotating distal capsule <NUM> directly (e.g., by grasping the distal capsule by hand) would not necessarily rotate rod <NUM>, and therefore would not result in movement of the distal capsule proximally over mount <NUM> and implant <NUM>. Therefore, for some applications, an accessory <NUM> is provided (<FIG>), attachment of which to distal portion <NUM> of implantation instrument <NUM> (e.g., to distal capsule <NUM>) rotationally locks distal capsule <NUM> to rod <NUM>, thereby allowing ensheathing of implant <NUM> within the distal capsule by rotating the distal capsule directly.

<FIG> shows distal portion <NUM> of implantation instrument <NUM>, with capsule assembly <NUM> open in the configuration shown in <FIG>, such that mount <NUM> is released proximally from the open end of distal capsule <NUM>. Implant <NUM> is introduced over the distal end of catheter system <NUM>, over and past distal capsule <NUM> (<FIG>). For applications in which implant <NUM> is a prosthetic valve, distal capsule <NUM> typically moves with respect to the leaflets of the valve in an upstream-to-downstream direction (e.g., from an upstream end of the prosthetic valve to a downstream end of the prosthetic valve, as described hereinbelow with reference to prosthetic valve <NUM> shown in frame A of <FIG>). Subsequently, accessory <NUM> is attached to distal portion <NUM> of implantation instrument <NUM> (e.g., to distal capsule <NUM>) (<FIG>).

Typically, accessory <NUM> comprises (or defines) a detent <NUM>, and is configured to be attached to distal capsule <NUM> such that the detent rotationally locks the distal capsule to rod <NUM>. For some applications, distal capsule <NUM> defines a detent-hole <NUM>, and the attachment of accessory <NUM> to the distal capsule is such that detent <NUM> extends through the detent-hole to rotationally lock the distal capsule to rod <NUM>. For some such applications, delivery tool <NUM> (e.g., catheter system <NUM> thereof) comprises a catch to which detent <NUM> may be engaged. For example, catheter system <NUM> may define a recess <NUM> (<FIG>) into which detent <NUM> becomes disposed. For some applications, catheter system <NUM> comprises a ring <NUM> that is rotationally and axially fixed with respect to rod <NUM>, and that defines recess <NUM> (see <FIG>, and <FIG>). For some applications, rod <NUM> defines ring <NUM> and/or recess <NUM>.

For some applications, accessory <NUM> comprises a c-shaped clip <NUM>, and is attached to distal capsule <NUM> by being placed over the distal capsule (e.g., snapped into place). For such applications, detent <NUM> is attached to clip <NUM>, and typically extends radially inward from its point of attachment to the clip.

For some applications, a knob <NUM> is subsequently introduced over the distal end of catheter system <NUM> (<FIG>), and is engaged with clip <NUM> (and optionally with distal capsule <NUM>), to facilitate rotation by hand of distal capsule <NUM> with respect to rod <NUM>.

As shown in <FIG>, implant <NUM> is then compressed ("crimped") such that the implant engages mount <NUM>, e.g., with adaptors <NUM> being received by respective slots <NUM>.

Subsequently, and as shown in <FIG>, distal capsule <NUM> and rod <NUM> are hand-rotated in a first rotational direction (e.g., by grasping the distal capsule, accessory <NUM>, and/or knob <NUM>), such that rod <NUM> screws into shaft <NUM>, thereby screwing the distal capsule proximally over implant <NUM> and mount <NUM>. In this way, at least the downstream end of the implant is ensheathed by the distal capsule, while maintaining the engagement between the implant and the mount. Therefore, implant <NUM> is ensheathed in distal capsule <NUM> by moving the distal capsule helically over the implant, but is unsheathed by moving the distal capsule linearly off of the implant, as described hereinabove with reference to <FIG> and <FIG>. For some applications, and as shown in <FIG>, proximal capsule <NUM> is advanced distally over the upstream end of implant <NUM>, further ensheathing the implant within capsule assembly <NUM>.

Subsequently to ensheathing the implant, and yet prior to capsule assembly <NUM> being used to deliver implant <NUM>, accessory <NUM> (and knob <NUM>, if present) is removed (<FIG>). Removing accessory <NUM> from distal capsule <NUM> rotationally unlocks the distal capsule with respect to rod <NUM>, such that the unsheathing force (e.g., rotation of the rod in a second rotational direction) moves the distal capsule linearly off of the implant.

In any case, if actuator <NUM> was initially not engaged with rod <NUM> or was disengaged by the operator from rod <NUM> prior to ensheathing implant <NUM> in distal capsule <NUM>, then actuator <NUM> is engaged (or reengaged) with rod <NUM> prior to implantation of the implant. Typically for such applications, the unsheathing force is then applied to distal portion <NUM> of implantation instrument <NUM> via actuator <NUM>.

Reference is made to <FIG>, which are schematic illustrations showing a delivery tool <NUM>.

<FIG> shows delivery tool <NUM> assembled, and <FIG> shows an exploded view of a distal portion <NUM> of the delivery tool. As shown, delivery tool <NUM> comprises an extracorporeal controller <NUM> and distal portion <NUM> that is dimensioned for transluminal (e.g., transfemoral) delivery to a subject.

Delivery tool <NUM> bears certain similarities to delivery tool <NUM> described hereinabove. Particularly, distal portion <NUM> of delivery tool <NUM> is in certain ways similar to distal portion <NUM> of implantation instrument <NUM> of delivery tool <NUM>. Components that are identically named between delivery tools <NUM>, <NUM> typically share similar features and serve similar functions as each other.

As shown, distal portion <NUM> comprises a shaft <NUM> (e.g., extending distally from within a capsule catheter <NUM>) to which a proximal capsule <NUM> and a distal capsule <NUM> (collectively defining a capsule assembly <NUM>) are coupled. As shown in <FIG>, each capsule <NUM>, <NUM> has a respective open end <NUM>, <NUM>, such that open end <NUM> of proximal capsule <NUM> faces the proximal end of distal capsule <NUM>. For some applications, and as shown, open end <NUM> is the proximal end of distal capsule <NUM>, such that open end <NUM> of proximal capsule <NUM> faces the open end of the distal capsule.

Similarly to distal portion <NUM> of instrument <NUM> described hereinabove, distal portion <NUM> further comprises a mount <NUM> dimensioned (e.g., defining slots <NUM>) to engage an implant. Typically, capsules <NUM>, <NUM> can be moved with respect to the mount (e.g., along a distal portion axis ax1018), via extracorporeal controller <NUM>. For some applications, extracorporeal controller <NUM> controllably moves proximal capsule <NUM> and/or distal capsule <NUM> both distally ("advanced") and proximally ("retracted"), with respect to mount <NUM>.

For some applications, and as shown in <FIG>, distal portion <NUM> comprises a rod <NUM> that extends out of a distal end of shaft <NUM>. Similarly to as described hereinabove with reference to rod <NUM> of instrument <NUM>, delivery tool <NUM> is configured to distally advance distal capsule <NUM> with respect to mount <NUM> by screwing the rod through shaft <NUM>.

For some such applications, and further similarly to distal capsule <NUM> of instrument <NUM>, distal capsule <NUM> is rotationally coupled to and rotationally movable with respect to rod <NUM>, such that rotation of rod <NUM> does not necessarily rotate distal capsule <NUM>. Typically for such applications, pins <NUM> are fitted within distal capsule <NUM>, in relation to a recess <NUM> defined by rod <NUM>, so as to axially fix the distal capsule with relation to the rod, while allowing rotation of the rod with respect to the pins, as described hereinabove with reference to instrument <NUM> regarding <FIG> and <FIG>.

For some such applications, and as shown, distal capsule <NUM> defines a window <NUM>, and a hole <NUM> Typically for such applications, hole <NUM> is shaped to facilitate attachment of accessory <NUM> and/or knob <NUM> (not shown in <FIG>, yet described hereinabove with reference to <FIG>) in order to rotationally lock the distal capsule with respect to rod <NUM>. For example, rotationally locking distal capsule <NUM> to rod <NUM> may be facilitated by extending a portion of accessory <NUM> through hole <NUM> such that the portion occupies a recess <NUM> defined by a ring <NUM> that is fixedly coupled to the rod.

Notwithstanding similarities between delivery tools <NUM> and <NUM>, the description below of delivery tool <NUM> focuses upon features that are particular to delivery tool <NUM>. A difference between delivery tools <NUM> and <NUM> lies in distal portion <NUM> being configured to be transluminally advanced to the heart while in a delivery state (<FIG> and <FIG>) in which an inter-capsule gap 1071a exists between proximal capsule <NUM> and distal capsule <NUM> (e.g., between respective open ends <NUM>, <NUM>).

Typically for applications in which capsules <NUM>, <NUM> can be both advanced and retracted, the capsules may be moved axially to a range of positions, relative to mount <NUM>. For some such applications, and as shown in <FIG>, segments 1034c and 1034d of shaft <NUM> may be slidably coupled to each other, thereby facilitating axial movement of capsules <NUM>, <NUM>. Thus, and as shown in <FIG>, segments 1034c and 1034d may slide telescopically with respect to each other, such that distal portion <NUM> assumes a deployment state in which inter-capsule gap 1071b is longer than gap 1071a when the distal portion is in the delivery state (<FIG>).

Inter-capsule gap 1071b is typically at least <NUM>% (e.g., at least <NUM>%) and/or less than <NUM>% (e.g., less than <NUM>%) greater than inter-capsule gap 1071a.

For some applications, while distal portion <NUM> is in the delivery state, inter-capsule gap 1071a is greater than <NUM> (e.g., greater than <NUM>, e.g., greater than <NUM>, e.g., greater than <NUM>, e.g., greater than <NUM>) and/or less than <NUM> in length (e.g., less than <NUM>, e.g., less than <NUM>, e.g., less than <NUM>, e.g., less than <NUM>). For example, inter-capsule gap 1071a may be <NUM>-<NUM>.

For some such applications, while distal portion <NUM> is in the deployment state, inter-capsule gap 1071b is greater than <NUM> (e.g., greater than <NUM>, e.g., greater than <NUM>, e.g., greater than <NUM>, e.g., greater than <NUM>) and/or less than <NUM> in length (e.g., less than <NUM>, e.g., less than <NUM>, e.g., less than <NUM>, e.g., less than <NUM>). For example, inter-capsule gap 1071b may be <NUM>-<NUM>.

For some applications, proximal capsule <NUM> may be further advanced, and/or distal capsule <NUM> may be further retracted, such that distal portion <NUM> assumes a withdrawal state in which the inter-capsule gap is shorter than when the distal portion is in the delivery state (e.g., such that the gap is closed or nearly-closed, as shown in <FIG>). Consequently, for some such applications, a capsule-assembly length 1074c from a proximal end of proximal capsule <NUM> to a distal end of distal capsule <NUM> is lesser while distal portion <NUM> is in the withdrawal state (<FIG>) than capsule-assembly length 1074a while the distal portion is in the delivery state (<FIG>).

Although the states (e.g., delivery state, deployment state, withdrawal state) of delivery tool <NUM> are described with respect to distal portion <NUM>, they are typically implemented by controller <NUM>. For example, controller <NUM> may define these states as discrete states by enforcing only certain operations and/or degrees of movement of control elements (e.g., knobs, switches, levers, wheels etc.) of controller <NUM>, the control elements being operatively coupled to capsules <NUM> and <NUM>, e.g., by wires, rods, and/or cables. Furthermore, for some applications, the orders of operation described hereinbelow are facilitated and/or enforced by controller <NUM>, e.g., by the controller selectively and/or sequentially locking and/or unlocking locks that selectively and/or sequentially enable and/or disable the control elements of the controller.

Reference is made to <FIG>, which is a schematic illustration showing delivery tool <NUM> while prosthetic valve <NUM> has assumed an expanded state. Prosthetic valve <NUM> comprises a frame assembly <NUM> (shown in frame A), within which prosthetic leaflets <NUM> are disposed (frame B).

Prosthetic valve <NUM> is in certain ways similar to that described in <CIT> (e.g., with reference to <FIG>, <FIG>, and <FIG> thereof). For some applications, delivery tool <NUM> may be used to deliver implant (prosthetic valve) <NUM> of <CIT> Prosthetic valve <NUM> is typically self-expanding.

As shown in frame A of <FIG>, frame assembly <NUM> comprises an inner valve frame <NUM> nested within an outer frame <NUM>. Valve frame <NUM> is typically shaped to define: (i) a tubular portion <NUM> that defines a lumen <NUM> between an upstream end <NUM> and a downstream end <NUM>, and (ii) a plurality of arms <NUM> that collectively form an upstream support portion <NUM> that extends upstream from the tubular portion. For some applications, and as shown, valve frame <NUM> further defines adaptors <NUM>, and mount <NUM> engages adaptors <NUM> (e.g., by receiving adaptors <NUM> into slots <NUM> defined by the mount).

As shown, outer frame <NUM> comprises flanges <NUM>, which are each coupled to tubular portion <NUM> at a respective coupling point <NUM> that is disposed downstream of upstream support portion <NUM>. In this way, each flange <NUM> extends upstream from coupling point <NUM>, to a respective flange end-portion <NUM>.

Typically, and as shown in frame B, prosthetic valve <NUM> comprises a plurality of prosthetic leaflets <NUM>, which are disposed within lumen <NUM> so as to facilitate unidirectional blood flow from upstream end <NUM> to downstream end <NUM>. For some applications, and as shown, prosthetic valve <NUM> also comprises an upstream covering <NUM>, disposed over arms <NUM> to define an upstream skirt, in order to reduce a risk of paravalvular leakage.

Reference is made to <FIG>, which are schematic illustrations showing prosthetic valve <NUM> being restrained in a compressed state by delivery tool <NUM>. <FIG> therefore shows delivery system <NUM> in a delivery state (described hereinabove in reference to <FIG> and <FIG>) in which the system is configured to be transluminally advanced to the heart of a subject.

In the delivery state, a distal-implant portion <NUM> comprising a distal portion of valve frame <NUM> (e.g., downstream end <NUM> of tubular portion <NUM>) is engaged with mount <NUM> (e.g., by slots <NUM> receiving adaptors <NUM>), such that the downstream end and the mount are both disposed within distal capsule <NUM> (e.g., within a chamber defined by the distal capsule), with the distal capsule restraining the downstream end compressed against the mount, thereby maintaining engagement of the downstream end with the mount.

In the delivery state, a proximal-implant portion <NUM> comprising a proximal portion of valve frame <NUM> (e.g., upstream support portion <NUM>) is disposed within (e.g., restrained by) proximal capsule <NUM>. Additionally, in the delivery state, each flange end-portion <NUM> is disposed within (e.g., restrained by) proximal capsule <NUM>.

Typically, a segment <NUM> of prosthetic valve <NUM> is disposed at inter-capsule gap 1071a. That is, segment <NUM> is exposed by inter-capsule gap 1071a. Typically, segment <NUM> includes part of tubular portion <NUM>, part of each flange <NUM>, and/or coupling points <NUM>.

For some applications, and as shown in <FIG>, delivery tool <NUM> comprises a flexible sheath <NUM> (e.g., comprising a polymer and/or a fabric) that covers segment <NUM> by circumscribing inter-capsule gap 1071a. For some such applications, a distal end of the sheath may abut, and/or be partially disposed within, distal capsule <NUM>.

For some such applications, and as shown, sheath <NUM> extends proximally from inter-capsule gap 1071a, covering proximal capsule <NUM>. Sheath <NUM> may extend into and through a delivery catheter <NUM> that connects distal portion <NUM> to extracorporeal controller <NUM> (<FIG>), e.g., with a proximal end of the sheath remaining outside of the subject.

For some applications, distal portion <NUM> of delivery tool <NUM> comprises a nosecone <NUM> having a flexible distal end-portion <NUM>. For some such applications, and as shown in <FIG>, distal end-portion <NUM> has a resting shape (e.g., in the absence of a straightening force that may be provided by a more rigid element such as a guidewire <NUM>) that is curled. <FIG> shows distal end-portion <NUM> having been straightened by guidewire <NUM> having been extended through capsule catheter <NUM> and shaft <NUM>, and into the distal end-portion. Typically for such applications, an axial length d1025, d1025b of nosecone <NUM> is greater when guidewire <NUM> is disposed within the distal end-portion (<FIG>), than in the absence of the guidewire (e.g., length d1025, d1025a in <FIG>). For some such applications, shape-memory of distal end-portion <NUM> tends to maintain the distal end-portion in the resting (e.g., curled) shape. That is, even after having been straightened by guidewire <NUM>, distal end-portion <NUM> automatically assumes the curled shape when the guidewire is removed from the distal end-portion. It is hypothesized by the inventors that this curling of nosecone <NUM> advantageously allows the nosecone to be longer (and therefore have a shallower taper-angle) than a similar nosecone that does not curl, because it is possible to allow the nosecone to curl during steps in which a long axial length of a nosecone would otherwise be disadvantageous - e.g., as described hereinbelow with respect to <FIG>.

Reference is made to <FIG>, which are schematic illustrations showing delivery tool <NUM> being used to deploy prosthetic valve <NUM> at a tricuspid valve <NUM> of a heart <NUM> of a subject.

<FIG> shows distal portion <NUM> of delivery tool <NUM> having been transluminally advanced, through inferior vena cava <NUM> and right atrium <NUM> of heart <NUM>, such that nosecone <NUM> and distal capsule <NUM> have passed through tricuspid valve <NUM> to enter right ventricle <NUM>.

For some applications, delivery tool <NUM> is transluminally advanced along guidewire <NUM> (e.g., after the guidewire is advanced to heart <NUM>). In this way, guidewire <NUM> extends from extracorporeal controller <NUM> to delivery catheter <NUM>. For some applications, controller <NUM> is used to manipulate guidewire <NUM> (e.g., to steer the guidewire while the guidewire advances to the heart). Alternatively or in addition, steering of distal portion <NUM> may be facilitated by delivery tool <NUM> comprising at least one pull-wire operatively connecting distal portion <NUM> to controller <NUM>. For example, delivery catheter <NUM> may be implemented using catheter system <NUM> described hereinabove with reference to <FIG> and <FIG>, such that capsule catheter <NUM> and shaft <NUM> extend through the catheter system, mutatis mutandis.

For some applications, steering of distal portion <NUM> may be further facilitated by shaft <NUM> having segments distinguished by their relative rigidity. Typically for such applications, shaft <NUM> extends distally from a proximal portion (e.g., from extracorporeal controller <NUM>) of delivery tool <NUM> (e.g., within delivery catheter <NUM> and capsule catheter <NUM>, as shown in the insets on the left side of <FIG>). For some such applications, a rigid proximal shaft segment 1034a (lower left inset of <FIG>) extends distally from extracorporeal controller <NUM>. Typically for such applications, rigid proximal shaft segment 1034a is greater than <NUM> (e.g., e.g., greater than <NUM>, e.g., greater than <NUM>, e.g., greater than <NUM>, e.g., greater than <NUM>) and/or less than <NUM> (e.g., e.g., less than <NUM>, e.g., less than <NUM>, e.g., less than <NUM>, e.g., less than <NUM>) in length. It is hypothesized by the inventors that rigidity of rigid proximal shaft segment 1034a facilitates transfer of force from the proximal portion of delivery tool <NUM> (e.g., from extracorporeal controller <NUM>).

For some applications, as described hereinabove, a distal shaft segment 1034b is relatively less rigid than proximal shaft segment 1034a, and is configured to be sufficiently flexible to turn from the vena cava toward tricuspid <NUM> (as shown in <FIG>). Flexible shaft segment 1034b of shaft <NUM> extends distally from rigid proximal shaft segment 1034a (upper left inset of <FIG>). For some such applications, flexible shaft segment 1034b is greater than <NUM> (e.g., greater than <NUM>, e.g., greater than <NUM>,) and/or less than <NUM> (e.g., less than <NUM>, e.g., less than <NUM>) in length.

For some applications, a rigid distal shaft segment extends distally from flexible shaft segment 1034b, such that the rigid distal shaft segment reaches distal portion <NUM> of delivery tool <NUM>. That is, as shown in <FIG>, rigid distal shaft segments 1034c and/or 1034d extend through at least part of capsules <NUM>, <NUM>. For example, rigid distal shaft segments 1034c and/or 1034d may extend distally out of proximal capsule <NUM>. It is hypothesized by the inventors that rigidity of rigid distal shaft segments 1034c and/or 1034d may ensure alignment of capsules <NUM>, <NUM> along distal portion axis ax1018, thereby facilitating axial movement of capsules <NUM>, <NUM> along the distal portion axis.

For some such applications, mount <NUM> is attached to the rigid distal shaft segment (e.g., rigid distal shaft segment 1034d, as shown). Typically for such applications, prosthetic valve <NUM> is compressed upon rigid distal shaft segments 1034c and/or 1034d.

For some such applications, rigid distal shaft segments 1034c, 1034d may slide telescopically with respect to each other, as described hereinabove in reference to <FIG>. Therefore, while distal portion <NUM> is in the delivery state, rigid distal shaft segments 1034c, 1034d may together be greater than <NUM> (e.g., greater than <NUM>, e.g., greater than <NUM>, e.g., greater than <NUM>) and/or less than <NUM> (e.g., less than <NUM>, e.g., e.g., less than <NUM>) in length.

For some such applications, rigid proximal shaft segment 1034a (bottom left inset of <FIG>), as well as rigid distal shaft segments 1034c and 1034d, may each be more rigid than flexible shaft segment 1034b (upper left inset of <FIG>).

It is hypothesized by the inventors that the relative flexibility of flexible shaft segment <NUM>, 1034b facilitates steering of distal portion <NUM>, particularly from inferior vena cava <NUM> to right ventricle <NUM>. It is further hypothesized by the inventors that the relative rigidity of rigid proximal shaft segment <NUM>, 1034a provides support (e.g., a resistance force) that facilitates steering of distal portion <NUM>. Additionally, the relative rigidity of rigid distal shaft segments <NUM>, 1034c, 1034d is further hypothesized by the inventors to facilitate maintenance of the alignment of the capsules along linear distal portion axis ax1018, e.g., while distal portion <NUM> transitions between delivery state, deployment state and withdrawal state, as described hereinabove.

<FIG> shows distal end-portion <NUM> as it is straightened by guidewire <NUM>, as described hereinabove. For some applications, it may be desirable to reduce axial length d1025 of nosecone <NUM> (<FIG>), prior to deploying prosthetic valve <NUM> at the native valve. Typically for such applications, and as shown in <FIG>, guidewire <NUM> is withdrawn from at least distal end-portion <NUM>, thereby reducing axial length d1025 of nosecone <NUM> (as described hereinabove with reference to <FIG>). It is hypothesized by the inventors that reducing length d1025 by withdrawing guidewire <NUM> may facilitate deployment of prosthetic valve <NUM> by reducing an amount of space within right ventricle <NUM> required to maneuver distal portion <NUM> (e.g., distal capsule <NUM> thereof).

<FIG> shows distal portion <NUM> of delivery tool <NUM> after guidewire <NUM> has been proximally withdrawn from distal end-portion <NUM> of nosecone <NUM>.

<FIG> shows flexible sheath <NUM> having been subsequently retracted, exposing segment <NUM> and proximal capsule <NUM>. For the sake of clarity, and similarly to as in <FIG>, distal portion <NUM> is shown as if proximal capsule <NUM> and distal capsule <NUM> were transparent, in order to visualize the orientation of prosthetic valve <NUM> within the respective capsules. As shown, mount <NUM> and the downstream end of tubular portion <NUM> are disposed within distal capsule <NUM>, whereas upstream support portion <NUM> and flange end-portions <NUM> are disposed within proximal capsule <NUM>, as described hereinabove in reference to <FIG>.

Subsequently, proximal capsule <NUM> is partially retracted with respect to mount <NUM>, such that flange end-portions <NUM> are released from the proximal capsule (<FIG>). Since outer frame <NUM> typically comprises a shape-memory elastic material (e.g., Nitinol), flanges <NUM> (e.g., end-portions <NUM> thereof) automatically expand radially outward from coupling points <NUM> (<FIG>), upon release from proximal capsule <NUM>. However, since the distal end of tubular portion <NUM> is still restrained by distal capsule <NUM>, and upstream support portion <NUM> is still restrained by proximal capsule <NUM>, valve frame <NUM> remains in the compressed state.

The inset of <FIG> shows a mechanism by which, for some applications, proximal capsule <NUM> is retracted. (The proximal capsule is shown in the inset without the prosthetic valve, for the sake of simplicity.

For some applications, and as shown, delivery tool <NUM> (e.g., controller <NUM> thereof) is configured to retract and/or advance proximal capsule <NUM> by translating rotational motion of capsule catheter <NUM> into longitudinal motion of the proximal capsule along axis ax1018. For this purpose, a disc-assembly <NUM>, comprising a proximal disc <NUM> that is rotationally coupled to and rotationally movable with respect to a distal disc <NUM>, is typically fitted within proximal capsule <NUM>. Further typically, the exterior of proximal disc <NUM> defines external screw threading that is complementary to internal screw threading <NUM> defined by the interior of proximal capsule <NUM>. Further typically for such applications, and as shown, the proximal capsule <NUM> is shaped to define a longitudinal track <NUM> that traverses internal threading <NUM>.

Since proximal disc <NUM> is fixedly coupled to capsule catheter <NUM>, rotation of capsule catheter <NUM> with respect to shaft <NUM> (e.g., via controller <NUM>) screws the proximal disc along internal threading <NUM> of proximal capsule <NUM>. At the same time, distal disc <NUM> is inhibited from rotating because distal disc <NUM>: (i) is fixedly coupled to shaft <NUM>, and (<NUM>) engages track <NUM> of proximal capsule <NUM> (e.g., by locking pin <NUM> having been fitted into the track). Thus, screwing of proximal disc <NUM> pushes distal disc <NUM> along track <NUM>, thereby translating rotational movement of the proximal disc into axial movement <NUM> (e.g., retraction) of proximal capsule <NUM> with respect to disc-assembly <NUM>, as well as to mount <NUM>.

<FIG> shows continued deployment of prosthetic valve <NUM> at tricuspid valve <NUM>. Distal portion <NUM> has been retracted as a whole, relative to tissue of heart <NUM>, and to delivery catheter <NUM>. In this way, flanges <NUM> (e.g., end-portions <NUM> thereof) now engage tissue (e.g., leaflets) of tricuspid valve <NUM>.

In the following deployment step shown in <FIG>, proximal capsule <NUM> has been further retracted, thereby releasing upstream support portion <NUM> from the proximal capsule, such that the upstream support portion expands radially outward. As shown, proximal capsule <NUM> is retracted proximally with respect to capsule catheter <NUM> and delivery catheter <NUM>. Proximal capsule <NUM> therefore typically has an internal diameter that is large enough to allow for the proximal capsule to be retracted over capsule catheter <NUM> and/or delivery catheter <NUM>.

Similarly to outer frame <NUM>, valve frame <NUM> also typically comprises a shape-memory material, such that upstream support portion <NUM> expands automatically upon release from proximal capsule <NUM>. In this way, tissue of tricuspid valve <NUM> is squeezed between upstream support portion <NUM> and the flanges <NUM>.

<FIG> shows distal capsule <NUM> having been advanced with respect to mount <NUM>, such that distal portion <NUM> assumes the deployment state described hereinabove in reference to <FIG>. Release of mount <NUM> and tubular portion <NUM> from the distal capsule allows tubular portion <NUM> to automatically expanded radially outward, such that frame assembly <NUM> (and therefore prosthetic valve <NUM> as a whole) has assumed its expanded state.

Once prosthetic valve <NUM> is fully expanded at tricuspid valve <NUM>, it is desirable to withdraw distal portion <NUM> from heart <NUM>. In order to reduce a likelihood of distal capsule <NUM> (e.g., open end <NUM> thereof) undesirably engaging valve <NUM> (e.g., leaflets thereof) during upstream retraction through lumen <NUM>, proximal capsule <NUM> is first advanced downstream through lumen <NUM>, thereby closing inter-capsule gap 1071b (e.g., such that open end <NUM> of the proximal capsule abuts open end <NUM> of the distal capsule), as shown in <FIG> and <FIG>. As described hereinabove in reference to <FIG>, slidable coupling of segments 1034c and 1034d facilitates closure of gap 1071b. For some applications, and as shown in <FIG>, distal capsule <NUM> is partially retracted (e.g., such that the distal capsule again houses mount <NUM>), to facilitate closure of inter-capsule gap 1071b.

Alternatively or in addition to closing inter-capsule gap 1071b, withdrawal of distal portion <NUM> from heart <NUM> may be facilitated by guidewire <NUM> being re-advanced into distal end-portion <NUM> of nosecone <NUM>, either prior to or during retraction of distal portion <NUM> through lumen <NUM> of tubular portion <NUM>. Readvancing guidewire <NUM> into distal end-portion <NUM> typically straightens the distal end-portion, as described hereinabove in reference to <FIG> and <FIG>. It is hypothesized by the inventors that the straightening of nosecone <NUM> may facilitate withdrawal of distal portion <NUM> in a retrograde direction through prosthetic valve <NUM> (i.e., against the direction for which prosthetic leaflets <NUM> are configured to allow blood flow through prosthetic valve <NUM>), e.g., by reducing a likelihood of the nosecone ensnaring the prosthetic valve compared to when the nosecone is curled.

<FIG> shows the subsequent retraction of distal portion <NUM> through lumen <NUM> of tubular portion <NUM>. It is again noted that capsule assembly-length 1074c (<FIG>), while distal portion <NUM> assumes the withdrawal state, is less than capsule assembly-length 1074a of the distal portion in the delivery state (<FIG>). It is therefore hypothesized by the inventors that closing the inter-capsule gap 1071b facilitates transluminal removal of delivery tool <NUM> from the heart.

Except where noted, delivery tool <NUM> is typically identical to delivery tool <NUM> described hereinabove with reference to <FIG>, and is used similarly to the use of delivery tool <NUM>, mutatis mutandis. Components that are identically named between the systems typically share similar features and serve similar functions as each other. As such, the description below of delivery tool <NUM> focuses upon features that are particular to delivery tool <NUM>.

<FIG> shows delivery tool <NUM> assembled, and <FIG> shows an exploded view of a distal portion <NUM> of the delivery tool. As shown, delivery tool <NUM> comprises an extracorporeal controller <NUM> and a distal portion <NUM> that is dimensioned for transluminal (e.g., transfemoral) delivery to a subject.

As shown, distal portion <NUM> comprises a tubular shaft <NUM> (e.g., extending distally from within a capsule catheter <NUM>) to which a proximal capsule <NUM> and a distal capsule <NUM> (collectively defining a capsule assembly <NUM>) are coupled. For some applications, and in contrast to shaft <NUM>, shaft <NUM> does not necessarily comprise segments that are distinguishable by their relative rigidity.

As shown, each capsule <NUM>, <NUM> has a respective open end <NUM>, <NUM>, such that open end <NUM> of proximal capsule <NUM> faces open end <NUM> of distal capsule <NUM>. Typically, capsules <NUM>, <NUM> are axially moveable with respect to the shaft (e.g., along a central longitudinal axis ax2018), via extracorporeal controller <NUM>. For some applications, proximal capsule <NUM> and/or distal capsule <NUM> can be moved both distally ("advanced") and proximally ("retracted"), with respect to shaft <NUM>.

For some applications, and as shown, distal portion <NUM> further comprises a mount <NUM> that surrounds shaft <NUM> and that is dimensioned (e.g., defining slots <NUM>) to engage an implant. For some applications, distal capsule <NUM> is shaped to define an opening (e.g., a window) <NUM> that facilitates use of delivery capsule assembly <NUM> with an implant (e.g., by allowing a user to visualize mount <NUM> and/or a portion of the implant), as described hereinbelow with reference to <FIG>.

Typically, and as shown in <FIG>, distal portion <NUM> comprises a rod <NUM> having a distal portion that extends out of a distal end of shaft <NUM>. Similarly to as described hereinabove with reference to delivery tool <NUM>, delivery tool <NUM> is configured to distally advance distal capsule <NUM> with respect to mount <NUM> by screwing the rod through shaft <NUM>.

For some applications, and further similarly to delivery tool <NUM>, distal capsule <NUM> is rotationally movable with respect to rod <NUM>, such that rotation of rod <NUM> does not necessarily rotate distal capsule <NUM>. Typically for such applications, and as shown, pins <NUM> are fitted within distal capsule <NUM>, into a recess <NUM> defined by rod <NUM>, so as to axially fix the distal capsule with relation to the rod, while allowing rotation of the rod with respect to the pins, as described hereinabove.

In contrast to delivery tool <NUM>, and as shown, delivery tool <NUM> comprises a delivery stent <NUM> that is fixedly coupled to shaft <NUM>. Typically, delivery stent <NUM> comprises a shape-memory material, such that when an implant is crimped over the delivery stent and shaft <NUM> (as described hereinbelow with reference to <FIG>), the delivery stent assumes a compressed state within the implant. Delivery stent <NUM> is shown in <FIG> in an expanded state, without an implant.

Reference is made to <FIG>, which are schematic illustrations showing some steps of loading a prosthetic valve <NUM> onto a distal portion <NUM> of a delivery tool <NUM>, resulting in apparatus in accordance with some applications of the invention.

Except where noted, delivery tool <NUM> is in many ways similar to delivery tool <NUM> described hereinabove with reference to <FIG>, and is used similarly as delivery tool <NUM>, mutatis mutandis. Components that are identically named between the systems typically share similar features and serve similar functions as each other. As such, the description below of delivery tool <NUM> focuses upon features that are particular to delivery tool <NUM>.

As shown in <FIG>, delivery tool <NUM> is a multi-catheter transluminal (e.g., transfemoral) delivery tool, comprising two primary components: a catheter system <NUM>, and an implantation instrument <NUM> at a proximal portion <NUM> of the delivery tool. Similarly to proximal part <NUM> of delivery tool <NUM> described hereinabove, implantation instrument <NUM> may be considered to be an extracorporeal control system of delivery tool <NUM>, and distal portion <NUM> is configured to be advanced into the subject.

Catheter system <NUM> comprises an outer catheter <NUM> coupled at a proximal end thereof to implantation instrument <NUM>. Instrument <NUM> comprises a plurality of tubular members that extend distally from proximal portion <NUM>, which are coaxial about a central longitudinal axis ax1 of delivery tool <NUM>, and which are discussed in more detail hereinbelow. The outermost of these tubular members is typically a delivery catheter <NUM> that extends distally from proximal portion <NUM>, through outer catheter <NUM>, out of an open distal end of catheter <NUM>.

Typically, and as shown, capsule catheter <NUM> extends distally through delivery catheter <NUM>, to proximal capsule <NUM> of capsule assembly <NUM>. As described hereinbelow with reference to <FIG>, capsule assembly <NUM> is used to encase prosthetic valve <NUM> during advancement toward the heart. Catheter system <NUM> further comprises an alignment mechanism <NUM> that is used to align proximal and distal capsules <NUM>, <NUM> during advancement to and/or withdrawal from the heart, as described hereinbelow.

<FIG> show attachment of an accessory, e.g., distal-capsule ensheathing tool <NUM>, to ensheathe a downstream end of prosthetic valve <NUM> in distal capsule <NUM>. For example, distal-capsule ensheathing tool <NUM> comprises a clip <NUM> and a knob <NUM>. Clip <NUM> is shaped to define a detent <NUM>, a portion of which is extended within a detent-hole <NUM>. By extending detent <NUM> through detent-hole <NUM>, the detent occupies at least a portion of a recess <NUM> defined by a ring <NUM> (<FIG>) that is fixedly coupled to rod <NUM>. In this way, distal capsule <NUM> is rotationally locked with respect to rod <NUM>. Knob <NUM> is typically attached over clip <NUM>, to facilitate manual rotation of the clip, and therefore of distal capsule <NUM> and rod <NUM>, with respect to shaft <NUM>. As described hereinabove with reference to delivery tool <NUM>, rotation of the rod with respect to the shaft screws the rod into the shaft, resulting in linear (e.g., proximal) movement of distal capsule <NUM> with respect to the shaft and to prosthetic valve <NUM>.

As shown in <FIG>, prosthetic valve <NUM> is then compressed ("crimped") using a crimping tool, around a distal portion of shaft <NUM>, such that the downstream end of the prosthetic valve engages mount <NUM>, e.g., with adaptors <NUM> being received by respective slots <NUM> (<FIG>). As prosthetic valve <NUM> is crimped (or subsequently thereto), an ensheathing force is applied to distal-capsule ensheathing tool <NUM>, e.g., by rotating knob <NUM> that is directly coupled to distal capsule <NUM>.

Direct application of the ensheathing force to distal capsule <NUM> may be desirable over applying the ensheathing force using implantation instrument <NUM> over the length of catheter system <NUM>, since direct application of the ensheathing force typically avoids resistance that may be encountered over a length of the catheter system.

For some applications, and as shown, distal capsule <NUM> defines an opening (e.g., window <NUM>). As shown in <FIG>, a user may use the opening to monitor proximal advancement of distal capsule <NUM> over mount <NUM> and prosthetic valve <NUM>. It is hypothesized by the inventors that use of window <NUM> to visualize the portion of prosthetic valve <NUM> (e.g., a downstream end of the prosthetic valve) that is ensheathed by distal capsule <NUM> increases the reliability of delivery tool <NUM>, e.g., by reducing a risk of premature release of the prosthetic valve from the distal capsule that may be caused by the user estimating which portion of the prosthetic valve is ensheathed within the distal capsule. Instead, window <NUM> allows the user to monitor the ensheathed portion of prosthetic valve <NUM>. For example, and as shown, distal capsule <NUM> is advanced over prosthetic valve <NUM> until a portion of mount <NUM> and/or the prosthetic valve (e.g., adaptors <NUM> thereof) are visible through window <NUM>. In this way, ensheathing prosthetic valve <NUM> by distal capsule <NUM> serves to maintain coupling between the prosthetic valve and mount <NUM> by ensuring that: (i) the mount surrounds adaptors <NUM>, and (ii) each adaptor remains within a respective slot <NUM> of the mount.

For some applications, and as shown, after ensheathing the downstream end of prosthetic valve <NUM> in distal capsule <NUM>, the upstream end of the prosthetic valve is ensheathed in proximal capsule <NUM>. The crimping tool is typically used to compress the proximal portion of prosthetic valve <NUM>, such that the proximal portion assumes the compressed state, as shown in <FIG>.

For some applications, a second ensheathing force is applied directly to distal portion <NUM> of delivery tool <NUM>. Similarly to as described hereinabove with reference to ensheathing the distal end of prosthetic valve <NUM> within distal capsule <NUM>, application of the ensheathing force directly to distal portion <NUM> may be desirable over applying the ensheathing force along the length of catheter system <NUM>, to avoid resistance that may be encountered over the length of the catheter system.

For some applications, a second accessory, e.g., a proximal-capsule ensheathing tool such as cuff <NUM>, is attached to distal portion <NUM> (<FIG>), for applying the second ensheathing force directly to distal portion <NUM>. For some applications, and as shown, cuff <NUM> comprises a user grip <NUM> that is shaped to facilitate rotation of the cuff with respect to distal portion <NUM>. For example, and as shown, cuff <NUM> may be directly coupled to a proximal disc <NUM> of a disc assembly <NUM> of distal portion <NUM>, in order to convert rotational movement of cuff <NUM> into axial motion of proximal capsule <NUM> over a proximal portion of prosthetic valve <NUM>.

Typically for such applications, and as shown, cuff <NUM> further comprises a distal coupling portion <NUM> that is configured to reversibly couple the cuff to proximal disc <NUM> of disc assembly <NUM>. For example, and as shown, distal coupling portion <NUM> comprises one or more pins <NUM> shaped so as to fit within respective holes <NUM> defined by the proximal disc <NUM>. Alternatively or in addition, distal coupling portion <NUM> is sized to fit within an opening in proximal disc <NUM>.

Similarly to disc assembly <NUM> (<FIG>), disc assembly <NUM> (<FIG>) comprises (i) proximal disc <NUM> that defines external screw threading that is complementary to internal screw threading defined by the interior of proximal capsule <NUM>, and (ii) a distal disc <NUM> that is rotationally coupled to and rotationally movable with respect to the proximal disc. Distal disc <NUM> is inhibited from rotating because the distal disc: (i) is fixedly coupled to shaft <NUM>, and (<NUM>) engages track <NUM> of proximal capsule <NUM> (e.g., by a locking pin <NUM> having been fitted into the track). Thus, screwing of proximal disc <NUM> using cuff <NUM> pushes distal disc <NUM> and locking pin <NUM> along track <NUM>, translating rotational movement of the proximal disc into advancement of proximal capsule <NUM> with respect to shaft <NUM> and over the proximal portion of prosthetic valve <NUM> (<FIG>).

Reference is made to <FIG>, which are schematic illustrations showing advancement of an alignment mechanism <NUM> over catheter system <NUM> of delivery tool <NUM>, in accordance with some applications of the invention.

Typically, and as shown, alignment mechanism <NUM> comprises a supplemental tube <NUM> that is coupled to a distal end of an elongate oversheath <NUM> at connecting portion <NUM>. Oversheath <NUM> is shaped so as to define an elongate-oversheath lumen, through which catheter system <NUM> (e.g., capsule catheter <NUM> thereof) is slidably passed, and supplemental tube <NUM> is shaped so as to define a supplemental-tube lumen that is sized for encasing at least a portion of a housing (e.g., capsule assembly <NUM>) during transluminal delivery of distal portion <NUM> of the delivery tool to the heart, and while retracting the housing out of a body of the subject, as described in greater detail hereinbelow.

Reference is made to <FIG>, which are schematic illustrations showing use of delivery tool <NUM> to advance prosthetic valve <NUM> toward heart <NUM> of a subject.

<FIG> show an operator using implantation instrument <NUM> to transfemorally advance distal portion <NUM> of delivery tool <NUM> to inferior vena cava <NUM>, toward heart <NUM>. As shown, supplementary tube <NUM> of alignment mechanism <NUM> encases a portion of capsule assembly <NUM> (e.g., proximal capsule <NUM>). For example, and as shown, supplementary tube <NUM> may abut distal capsule <NUM> while distal portion <NUM> is advanced toward the heart. Alternatively, supplementary tube <NUM> may encase a portion of distal capsule <NUM> during the advancement.

Typically, while distal portion <NUM> is in a delivery state (<FIG>), an upstream portion of prosthetic valve <NUM> is ensheathed by proximal capsule <NUM> and a downstream portion of the prosthetic valve is ensheathed by distal capsule <NUM>, such that an exposed segment <NUM> of prosthetic valve <NUM> is disposed at an inter-capsule gap that separates open end <NUM> of the proximal capsule from open end <NUM> of distal capsule <NUM>.

The upper inset of <FIG> shows distal portion <NUM> of delivery tool <NUM> in a delivery state in which an alignment tube <NUM> of alignment mechanism <NUM> is disposed between oversheath <NUM> and capsule catheter <NUM> of catheter system <NUM>. While distal portion <NUM> is in the delivery state, an aligner <NUM> of alignment mechanism <NUM> is typically disposed between alignment tube <NUM> and supplemental tube <NUM>. For some applications, and as shown, aligner <NUM> is shaped to form a ring that fits around alignment tube <NUM>. Aligner <NUM> typically comprises a material that is stiffer than capsule catheter <NUM>. For example, aligner <NUM> may comprise a metal or a polycarbonate.

Typically, and as shown, by occupying a space between capsule catheter <NUM> and supplemental tube <NUM>, aligner <NUM> is positioned to align the capsule catheter with respect to the supplemental tube (e.g., the aligner keeps a distal portion of the capsule catheter generally parallel with the supplemental tube). For some applications, and as shown, aligner <NUM> is coupled to a distal end of alignment tube <NUM>.

For some applications, aligner <NUM> and a distal portion of alignment tube <NUM> are axially slidable along the catheters (e.g., along capsule catheter <NUM>) of catheter system <NUM> (e.g., independently of supplemental tube <NUM>). For some such applications, aligner <NUM> and the distal portion of alignment tube <NUM> are axially slidable within the elongate-oversheath lumen and within the supplemental-tube lumen. For example, aligner <NUM> may be advanced distally to align capsule catheter <NUM> with respect to supplemental tube <NUM> before capsule assembly <NUM> is encased within the supplemental tube.

Elements comprising catheter system <NUM> and alignment mechanism <NUM> are typically dimensioned in order to facilitate sliding aligner <NUM> between the capsule catheter <NUM> and supplemental tube <NUM>. Therefore, for some applications, an inner diameter di2312 of aligner <NUM> is <NUM>-<NUM>, e.g., <NUM>, larger than an outer diameter do2072 of capsule catheter <NUM> (i.e., a largest catheter of catheter system <NUM> that passes through supplemental tube <NUM> and through aligner <NUM>), and/or an alignment-tube outer diameter do2314 of alignment tube <NUM> is <NUM>-<NUM>, e.g., <NUM>, smaller than a supplemental-tube inner diameter di2310 of supplemental tube <NUM>. An outer diameter of capsule catheter <NUM> is about <NUM> and an inner diameter of aligner <NUM> is about <NUM> by way of illustration and not limitation. A length of aligner <NUM> is typically between <NUM>-<NUM>, e.g., <NUM>.

Typically, supplemental tube <NUM> comprises material that is stiffer than elongate oversheath <NUM> of capsule catheter <NUM>. Alignment-tube outer diameter do2314 of alignment tube <NUM> is <NUM>-<NUM> smaller than an inner diameter of elongate oversheath <NUM>.

Typically for such applications, and as shown, a supplemental-tube outer diameter do2310 is larger than both (i) outer diameter do2072 of capsule catheter <NUM>, and (ii) an outer diameter do2320 of elongate oversheath <NUM>.

For some applications, during entry of delivery tool <NUM> within the body, supplemental tube <NUM> surrounds proximal capsule <NUM> and at least a proximal portion of distal capsule <NUM>, as well as exposed segment <NUM> of prosthetic valve <NUM>. Typically for such applications, subsequently to entering the body, proximal capsule <NUM> and the proximal portion of distal capsule <NUM> are exposed from within supplemental tube <NUM> (<FIG>) and are advanced toward the heart by distally advancing capsule catheter <NUM> with respect to oversheath <NUM> (e.g., by pushing capsule catheter <NUM> distally while retaining oversheath <NUM> in place and/or by retracting the oversheath proximally with respect to capsule catheter <NUM>.

Reference is made to <FIG>, which are schematic illustrations showing a delivery tool <NUM> that has an alignment mechanism <NUM>.

Delivery tool <NUM> is in many ways identical to delivery tool <NUM>, and is used in a similar way to delivery tool <NUM>, mutatis mutandis. Components bearing identical reference numerals are typically interchangeable between delivery tools <NUM> and <NUM>. For example, delivery tool <NUM> comprises implantation instrument <NUM>, and capsule assembly <NUM> at distal portion <NUM> of the delivery tool that is used to ensheathe prosthetic valve <NUM>. Components that are identically named between the systems typically share similar features and serve similar functions as each other. As such, the description below of delivery tool <NUM> focuses upon features that are particular to delivery tool <NUM>.

Similarly to alignment mechanism <NUM>, alignment mechanism <NUM> is used to align proximal and distal capsules <NUM>, <NUM> during advancement and/or retraction of delivery tool <NUM>, as described hereinbelow. Further similarly to alignment mechanism <NUM>, alignment mechanism <NUM> comprises a supplemental tube <NUM> that is used to encase a portion of capsule assembly <NUM> (<FIG>). As shown, and as described hereinabove regarding delivery tool <NUM>, while distal portion <NUM> of delivery tool <NUM> is in a delivery state, an aligner <NUM> of alignment mechanism <NUM> is typically disposed between an alignment tube <NUM> and supplemental tube <NUM>, to align capsule catheter <NUM> with respect to the supplemental tube. Further similarly to alignment mechanism <NUM> of tool <NUM>, proximal capsule <NUM> and the proximal portion of distal capsule <NUM> may be exposed from within supplemental tube <NUM> (<FIG>) and advanced toward the heart (not shown).

Delivery tool <NUM> comprises an aligner locking mechanism <NUM> that is operatively connected to alignment mechanism <NUM>. For some applications, and as shown, locking mechanism <NUM> comprises a sliding lock <NUM> that is: i) longitudinally fixed with respect to aligner <NUM>, and ii) slidable along a housing <NUM> of the locking mechanism <NUM>, and with respect to supplemental tube <NUM>. For example, and as shown, locking mechanism <NUM> may be fixedly connected to a proximal end of alignment tube <NUM>, and aligner <NUM> may be fixedly connected to a distal end of the alignment tube. In this way, longitudinal movement (e.g., along a proximal-to-distal axis) of sliding lock <NUM> results in similar longitudinal movement of aligner <NUM>. Therefore, sliding lock <NUM> from a proximal position (e.g., abutting a proximal endcap <NUM>, <FIG>) to a distal position (e.g., abutting a distal endcap <NUM> <FIG>) causes aligner <NUM> to slide distally within supplemental tube <NUM> from a proximal position (<FIG>) to a distal position (<FIG>).

In some cases, it may be desirable for aligner <NUM> to remain in the distal position while advancing and/or withdrawing distal portion <NUM>. Therefore, alignment mechanism <NUM> typically has a locked state (<FIG>) in which the aligner is fixedly disposed within the supplemental tube, as well as an unlocked state (<FIG>) in which aligner <NUM> is longitudinally slidable within supplemental-tube <NUM>. For some applications, the distal portion of alignment tube <NUM> transitions together with aligner <NUM> between the unlocked state and the locked state.

For example, and as shown, aligner <NUM> may be transitioned into the locked state (e.g., "locked") by sliding lock <NUM> past a catch <NUM> that protrudes from housing <NUM> of locking mechanism <NUM>. In this way, lock <NUM> is held snugly between distal endcap <NUM> and catch <NUM>.

Reference is made to <FIG> and to <FIG>, which are schematic illustrations showing use of delivery tools <NUM>, <NUM> to deploy prosthetic valve <NUM> at tricuspid valve <NUM> of the heart, and use of alignment mechanism <NUM>, <NUM> to facilitate withdrawal of the delivery tool from the subject.

Typically, and as shown, capsule catheter <NUM>, <NUM> and capsule assembly <NUM> encasing prosthetic valve <NUM> are advanced along a guidewire <NUM> through inferior vena cava <NUM> and into right atrium <NUM> of the heart. Further typically, prosthetic valve <NUM> remains ensheathed at least until distal capsule <NUM> is advanced into right ventricle <NUM> of the heart (<FIG>, <FIG>).

Similarly to prosthetic valve <NUM> described hereinabove with reference to <FIG>, prosthetic valve <NUM> typically comprises a tubular portion <NUM> in which a plurality of prosthetic leaflets are disposed, and that defines a lumen between an upstream end and a downstream end. For some applications, and as shown in <FIG>, tubular portion <NUM> and an upstream support portion <NUM> together define a valve frame <NUM>.

Typically for such applications, and as shown, a plurality of flanges <NUM> are coupled to tubular portion <NUM> at coupling points that are downstream of the upstream support portion. As shown, prosthetic valve <NUM> is engaged with delivery tool <NUM>, <NUM> such that a downstream end of tubular portion <NUM> is disposed within distal capsule <NUM>, and upstream support portion <NUM> and such that end-portions <NUM> of flanges <NUM> are disposed within proximal capsule <NUM>.

<FIG> and <FIG> show capsule assembly <NUM> having been advanced further distally, such that exposed segment <NUM> is partially disposed in right atrium <NUM>, and partially disposed in right ventricle <NUM>. Typically, and as shown, at least a portion of flanges <NUM> (e.g., end-portions <NUM> thereof) are still ensheathed within proximal capsule <NUM> at this stage.

<FIG> and <FIG> show capsule assembly <NUM> after guidewire <NUM> has been proximally withdrawn from distal end-portion <NUM> of nosecone <NUM>. As described hereinabove with reference to <FIG>, withdrawal of guidewire <NUM> from distal end-portion <NUM> reduces an axial length of nosecone <NUM>, facilitating deployment of prosthetic valve <NUM> by reducing an amount of space within right ventricle <NUM> required to maneuver capsule assembly <NUM> (e.g., distal capsule <NUM> thereof).

<FIG> and <FIG> show proximal capsule <NUM> having been partially retracted with respect to mount <NUM>, such that end-portions <NUM> of flanges <NUM> are released from the proximal capsule. Typically, an unsheathing force is applied extracorporeally to a controller, e.g., a knob or a dial of implantation instrument <NUM> in order to retract proximal capsule <NUM>. As shown, flanges <NUM> typically automatically expand radially outward from respective coupling points upon release from proximal capsule <NUM>. However, since the distal end of tubular portion <NUM> is still restrained by distal capsule <NUM>, and upstream support portion <NUM> is still restrained by proximal capsule <NUM>, valve frame <NUM> remains in the compressed state.

<FIG> and <FIG> show distal portion <NUM> having been advanced distally, such that flanges <NUM> enter right ventricle <NUM> (e.g., such that the flanges reach a point distal of leaflets <NUM> of tricuspid valve <NUM>). <FIG> and <FIG> show the distal portion having been retracted as a whole, relative to tricuspid valve <NUM>, such that flanges <NUM> (e.g., end-portions <NUM> thereof) engage tissue (e.g., the leaflets) of the tricuspid valve.

Subsequently, proximal capsule <NUM> is further retracted with respect to mount <NUM>, such that upstream support portion <NUM> is unsheathed from the proximal capsule (<FIG>, <FIG>), and distal capsule <NUM> is advanced with respect to mount <NUM>, such that tubular portion <NUM> is allowed to expand radially outward, such that prosthetic valve <NUM> assumes its expanded state. Typically, the unsheathing force is applied extracorporeally via implantation instrument <NUM> of delivery tools <NUM> and <NUM>, as described hereinabove with reference to <FIG>, mutatis mutandis.

As shown in <FIG> and <FIG>, distal movement of distal capsule <NUM> with respect to adaptors <NUM> and/or mount <NUM> (e.g., to a point that is further distal from the mount <NUM>, or at least to a point that is further distal from slots <NUM> thereof) releases the downstream end of tubular portion <NUM> from within distal capsule <NUM>. As shown, tubular portion <NUM> radially expands, allowing delivery stent <NUM> to expand to the expanded state.

<FIG> and <FIG> show proximal capsule <NUM> having advanced distally such that open end <NUM> of the proximal capsule meets delivery stent <NUM>. <FIG> and <FIG> show distal capsule <NUM> having advanced proximally such that open end <NUM> of the distal capsule meets delivery stent <NUM>. Typically, delivery stent <NUM> is configured to fit snugly between proximal and distal capsules <NUM>, <NUM>, in order to facilitate smooth retraction of capsule assembly <NUM> (e.g., the distal capsule thereof) through prosthetic valve <NUM> (<FIG>, <FIG>), with less risk of damaging the prosthetic leaflets that are disposed within tubular portion <NUM>. For some applications, delivery stent <NUM> comprises a fabric covering (not shown) that further facilitates smooth retraction of capsule assembly <NUM> through prosthetic valve <NUM>.

<FIG> and <FIG> show further retraction of distal portion <NUM> of delivery tool <NUM>, <NUM> from within prosthetic valve <NUM> and into inferior vena cava <NUM>. For some applications, distal portion <NUM> (e.g., capsule assembly <NUM> thereof) is retracted proximally toward supplemental tube <NUM>, <NUM> by proximally retracting capsule catheter <NUM>, <NUM> and/or delivery catheter <NUM>.

For some applications, and as shown in <FIG>, a distal portion of capsule catheter <NUM> is configured (e.g., is sufficiently flexible) to assume a curved orientation while the capsule catheter is retracted through the vasculature. As shown in the lower inset of <FIG>, there is sufficient space within the supplemental-tube lumen and capsule catheter <NUM> such that a distal portion of the capsule catheter <NUM> may assume the curved orientation. That is, supplemental tube <NUM> does not necessarily apply an aligning force to the distal portion of capsule catheter <NUM>. It is hypothesized by the inventors that fully retracting capsule assembly <NUM> into supplemental tube <NUM> while the distal portion of capsule catheter <NUM> is in the curved orientation may result in an imperfect fit of the capsule assembly into supplemental tube <NUM>, which may complicate withdrawal of distal portion <NUM> from the body.

For some applications, to promote better fit of capsule assembly <NUM> into supplemental tube <NUM>, and to facilitate withdrawal of distal portion <NUM> from the body, alignment tube <NUM> is positioned to orient aligner <NUM> so as to straighten the distal portion of capsule catheter <NUM>. <FIG> shows aligner <NUM> having moved distally e.g., by pushing alignment tube <NUM> proximally and/or by distally retracting capsule catheter <NUM>.

As shown in <FIG>, aligner <NUM> applies the aligning force upon capsule catheter <NUM>, straightening the distal portion of the capsule catheter. Typically for such applications, straightening the distal portion of capsule catheter <NUM> causes capsule assembly <NUM> and/or capsule catheter <NUM> to be concentrically disposed with respect to supplemental tube <NUM> while the capsule assembly is retracted into the supplemental tube, thereby avoiding entry of capsule assembly <NUM> into the supplemental tube at an angle.

Typically, distal portion <NUM> is then extracted from the body while the distal portion is housed within supplemental tube <NUM> (e.g., while supplemental tube <NUM> surrounds proximal capsule <NUM>, and while a distal end of the supplemental tube abuts the distal capsule).

As described hereinabove, and shown in <FIG>, catch <NUM> protrudes from housing <NUM> of locking mechanism <NUM>, holding lock <NUM> against distal endcap <NUM>, and thereby locking aligner <NUM> in the distal position. It is hypothesized by the inventors that locking aligner <NUM> in the distal position while withdrawing distal portion <NUM> from the body may simplify operation of delivery tool <NUM>, e.g., by obviating manual application of force in order to keep aligner <NUM> in the distal position.

As described hereinabove with reference to <FIG>, at least a portion of capsule assembly <NUM> is typically encased within supplemental tube <NUM> while distal portion <NUM> is withdrawn from the body. In order to allow for capsule assembly <NUM> to enter supplemental tube <NUM>, aligner <NUM> must typically be slid distally. Alignment mechanism <NUM> must therefore transition (e.g., be "unlocked") from the locked state to the unlocked state.

The embodiment of alignment mechanism <NUM> shown in <FIG> is unlocked by rotating lock <NUM> of locking mechanism <NUM> from state "A" to state "B. " As shown, lock <NUM> is rotated such that a groove <NUM> defined by the wall of the lock is aligned with catch <NUM>. In this way, lock <NUM> is no longer held snugly between catch <NUM> and distal endcap <NUM>, such that the lock and aligner <NUM> are allowed to move longitudinally in response to a force (e.g., in response to a pulling force being applied to the lock).

For some such applications, and as shown, rotation of lock <NUM> to unlock alignment mechanism <NUM> is facilitated by a pin <NUM>, that is fixedly coupled to alignment tube <NUM>, being disposed within a slot <NUM> that is defined by the lock. As shown, slot <NUM> is dimensioned such that rotation of lock <NUM> in alternate directions, such that pin <NUM> contacts opposite ends of the slot, reversibly locks or unlocks alignment mechanism <NUM>.

Rotation of lock <NUM> into state "B," such that groove <NUM> is aligned with catch <NUM>, facilitates movement of pin <NUM> along a longitudinal track <NUM>, such that lock <NUM> and aligner <NUM> each occupy their respective proximal positions (<FIG>). In this way, aligner <NUM> aligns capsule catheter <NUM> as capsule assembly <NUM> is retracted into supplemental tube <NUM>, and distal portion <NUM> may be extracted from the body.

Reference is made to <FIG>, which are schematic illustrations showing a delivery tool <NUM> being used to deploy prosthetic valve <NUM> at tricuspid valve <NUM> of the heart.

Except where noted, delivery tool <NUM> is typically identical to delivery tool <NUM> described hereinabove, and is used similarly to delivery tool <NUM>, mutatis mutandis. Components that are identically named between the systems typically share similar features and serve similar functions as each other, and components bearing identical reference numerals are typically interchangeable between delivery tools <NUM> and <NUM>. As such, the description below of delivery tool <NUM> focuses upon features that are particular to delivery tool <NUM>.

<FIG> shows delivery tool <NUM> within the heart, at a stage of deployment of prosthetic valve <NUM> comparable to that described hereinabove with reference to delivery tool <NUM> in <FIG>. In contrast to tool <NUM>, the proximal capsule of delivery tool <NUM> comprises a proximal capsule assembly <NUM> that has an inner proximal capsule 4064a and an outer proximal capsule 4064b. Typically, outer proximal capsule 4064b is longitudinally movable in relation to inner proximal capsule 4064a. For some applications, and as shown, inner proximal capsule 4064a fits snugly within outer proximal capsule 4064b.

For some applications, and as shown in <FIG>, proximal capsule assembly <NUM> defines an interior threading <NUM> similar to interior threading <NUM> that is defined by proximal capsule <NUM> of delivery tool <NUM>. For some such applications, and as shown in the insets of <FIG>, a proximal portion 4089p of interior threading <NUM> is defined by inner proximal capsule 4064a, and a distal portion of the interior threading is defined by outer proximal capsule 4064b. Typically for such applications, both proximal portion 4089p and distal portion 4089a of internal threading <NUM> are dimensioned to engage the external threading that is defined by proximal disc <NUM> of disc assembly <NUM>, as the proximal disc is screwed along the internal threading. For example, and as shown, threaded insets <NUM> of outer proximal capsule 4064b fit within windows defined by inner proximal capsule 4064a so as to engage proximal disc <NUM> (<FIG>).

Similarly to as described hereinabove regarding delivery tool <NUM> with reference to <FIG>, rotation of capsule catheter <NUM> with respect to shaft <NUM> screws proximal disc <NUM> along internal threading <NUM> of proximal capsule assembly <NUM>. At the same time, distal disc <NUM> is inhibited from rotating because distal disc <NUM>: (i) is fixedly coupled to shaft <NUM>, and (<NUM>) engages track <NUM> of proximal capsule assembly <NUM> (e.g., by locking pin <NUM> having been fitted into the track). Thus, screwing of proximal disc <NUM> pushes distal disc <NUM> along track <NUM>, thereby translating rotational movement of the proximal disc into axial movement (e.g., retraction) of proximal capsule assembly <NUM> with respect to disc-assembly <NUM>, as well as to prosthetic valve <NUM>.

As shown in <FIG>, rotation of capsule catheter <NUM> screws proximal disc <NUM> along internal threading <NUM>, causing proximal capsule assembly <NUM> to retract proximally with respect to disc-assembly <NUM>, which releases flange end-portions <NUM> from the proximal capsule assembly, as described hereinabove with reference to <FIG>. As shown, proximal capsule assembly <NUM> is retracted proximally with respect to capsule catheter <NUM> and delivery catheter <NUM>. Proximal capsule assembly <NUM> therefore typically has an internal diameter that is large enough to allow for the proximal capsule assembly to be retracted over capsule catheter <NUM> and/or delivery catheter <NUM>.

<FIG> shows continued deployment of prosthetic valve <NUM> at tricuspid valve <NUM>, in which distal portion <NUM> has been retracted as a whole, such that flanges <NUM> (e.g., end-portions <NUM> thereof) now engage tissue (e.g., leaflets) of tricuspid valve <NUM>.

In <FIG>, further screwing of proximal disc <NUM> along internal threading <NUM> causes outer proximal capsule 4064b to retract proximally with respect to inner proximal capsule 4064a, disc-assembly <NUM> and prosthetic valve <NUM>. As shown in the inset of <FIG>, outer proximal capsule 4064b is retracted over inner proximal capsule 4064a as proximal disc <NUM> advances from (a) proximal portion 4089p of internal threading <NUM> that is defined by the inner proximal capsule, to (b) distal portion 4089a of the internal threading that is defined by the outer proximal capsule.

Retraction of outer proximal capsule 4064b over inner proximal capsule 4064a causes proximal capsule assembly <NUM> to have a shorter length after releasing upstream support portion <NUM> than prior to releasing the upstream support. It is hypothesized by the inventors that this shortening of proximal capsule assembly <NUM> during deployment of prosthetic valve <NUM> may facilitate deployment, inter alia since a shorter proximal capsule assembly may be more easily retracted over a bent portion of capsule catheter <NUM> and/or delivery catheter <NUM>.

As shown, retraction of outer proximal capsule 4064b releases upstream support portion <NUM>, such that the upstream support portion expands radially outward. <FIG> shows distal capsule <NUM> having been advanced with respect to mount <NUM>, such that distal portion <NUM> assumes the deployment state described hereinabove in reference to <FIG> and <FIG>. Release of mount <NUM> and tubular portion <NUM> from the distal capsule allows the tubular portion to automatically expanded radially outward, such that frame assembly <NUM> (and therefore prosthetic valve <NUM> as a whole) has assumed its expanded state.

Claim 1:
Apparatus for use at a heart of a subject, the apparatus comprising:
a delivery tool (<NUM>) dimensioned for percutaneous delivery to the heart, the delivery tool (<NUM>) having a distal portion that defines a central longitudinal axis at the distal portion and comprises:
a shaft (<NUM>); and
a proximal capsule (<NUM>) and a distal capsule (<NUM>), each of the capsules:
having a respective open end, the open end (<NUM>) of the proximal capsule (<NUM>) facing the open end (<NUM>) of the distal capsule (<NUM>), and
coupled to the shaft (<NUM>) in a manner that allows axial movement of the capsule with respect to the shaft (<NUM>), along the central longitudinal axis at the distal portion; and
a prosthetic heart valve (<NUM>) comprising:
a tubular portion (<NUM>) that defines a lumen; and
a plurality of prosthetic leaflets disposed within the lumen,
wherein:
the prosthetic heart valve (<NUM>) is restrainable in a compressed state by the delivery tool (<NUM>), such that a downstream end of the tubular portion (<NUM>) is disposed within the distal capsule (<NUM>),
characterized in that the distal capsule (<NUM>) is shaped so as to define an opening (<NUM>) for visualizing ensheathing of at least a portion of the downstream end of the tubular portion (<NUM>) within the distal capsule (<NUM>).