Transcatheter prosthetic heart valve delivery device with support extension and method of loading prosthetic heart valve to delivery device

Abstract

A system includes a prosthetic heart valve and a delivery device. The prosthesis includes a stent frame that supports a valve structure. The stent frame is transitionable between a compressed state and an expanded state. The delivery device includes an outer shaft assembly and an inner shaft assembly. The outer shaft assembly includes a bladder extending distally from the outer shaft. The inner shaft assembly is coaxially received within the outer shaft assembly and includes an inner shaft, a valve holder, and a tip unit. A proximal section of the tip unit extends from the inner shaft and has a larger outer diameter than the inner shaft. In a delivery state, the prosthesis is received in a compressed state by the bladder over the inner shaft assembly, the first region of the stent frame is connected to the valve holder, and at least a portion of the second region of the stent frame contacts the proximal section of the tip unit.

Description

Technical Field

[0001] The present disclosure relates to catheter-based devices and systems for delivering prosthetic heart valves. More specifically, the present disclosure relates to transcatheter prosthetic heart valve delivery devices and corresponding methods of use. Background Art

[0002] The human heart includes four heart valves that define the path of blood flow through the heart: the mitral valve, tricuspid valve, aortic valve, and pulmonary valve. The mitral valve and tricuspid valve are atrioventricular valves, which are located between the atria and ventricles, while the aortic valve and pulmonary valve are semilunar valves, which are located in the arteries leaving the heart. Ideally, when the valve is in the open position, the native leaflets of the heart valve move apart from each other, and when the valve is in the closed position, these native leaflets meet or "close together". Possible problems with the valve include stenosis that causes the valve to not open normally and / or insufficiency or regurgitation that causes the valve to not close normally. Stenosis and insufficiency may occur concomitantly in the same valve. The effects of valvular dysfunction vary, with regurgitation or regurgitation typically causing relatively severe physiological consequences for the patient.

[0003] Diseased or otherwise defective heart valves can be repaired or replaced using a variety of different types of heart valve surgery. One conventional technique involves an open-heart surgical approach performed under general anesthesia, during which the heart is stopped and blood flow is controlled by a heart-lung bypass machine.

[0004] Recently, minimally invasive methods have been developed to facilitate the implantation of valve prostheses on a beating heart in a catheter-based manner, thereby aiming to avoid the need to use traditional sternotomy and cardiopulmonary bypass. Generally speaking, an expandable prosthetic valve is compressed around or within a catheter, inserted into a patient's body cavity (such as the femoral artery), and delivered to the desired location in the heart.

[0005] The heart valve prosthesis adopted by catheter-based procedures or transcatheter procedures generally includes an expandable multi-level framework or stent that supports a valve structure with multiple leaflets. The framework can be contracted during percutaneous intraluminal delivery and expand when deployed at or in the native valve. A type of valve stent can be initially provided in an expanded or uncollapsed state, and then folded or compressed around the balloon portion of the catheter. The balloon is then inflated to expand the prosthetic heart valve and deploy it. In the case of other stented prosthetic heart valve designs, the stent frame is formed to self-expand. In the case of these systems, the stent with valve is folded to the desired size and is kept in the sheath in this compressed state for transluminal delivery. Retracting the sheath from this stent with valve allows the stent to self-expand to a larger diameter, thereby being fixed at the native valve site. More generally, then, once the prosthetic valve is positioned at the treatment site (e.g., within a non-functional native valve), the stent frame structure can be expanded to securely hold the prosthetic valve in place. An example of a stented prosthetic valve is disclosed in U.S. Pat. No. 5,957,949 to Leonhardt et al., the entire contents of which are incorporated herein by reference.

[0006] The present disclosure addresses problems and limitations associated with the related art. Summary of the invention

[0007] Some aspects of the present disclosure relate to a system including a prosthetic heart valve and a delivery device. The prosthetic heart valve includes a stent frame and a valve structure. The stent frame can be transformed between a compressed state and an expanded state. The valve structure is supported by the stent frame. A first area of ​​the stent frame extends longitudinally beyond the valve structure in a first direction, and a second area of ​​the stent frame extends longitudinally beyond the valve structure in a second direction opposite to the first direction. The delivery device includes an outer shaft assembly and an inner shaft assembly. The outer shaft assembly includes a capsule extending distally from the outer shaft. The inner shaft assembly is coaxially received in the outer shaft assembly and includes an inner shaft, a valve retainer and a terminal unit. The valve retainer is maintained by the inner shaft. The terminal unit extends distally from the inner shaft and defines a proximal segment, a distal segment opposite to the proximal segment, and an intermediate segment between the proximal segment and the distal segment. The outer diameter of the proximal segment is greater than the outer diameter of the inner shaft. The outer diameter of the intermediate segment is greater than the outer diameter of the proximal segment. The outer diameter of the tip unit increases at a transition from the middle section to the distal section. The system is configured to provide a delivery state in which the prosthetic heart valve is contained by the capsule in a compressed state over the inner shaft assembly, the first region of the stent frame is connected to the valve retainer, and at least a portion of the second region of the stent frame contacts the proximal section of the tip unit.

[0008] In some embodiments, the tip unit minimizes or prevents strut crossing and / or infolding along the second zone, for example, when loading the prosthetic heart valve into a delivery device. As a reference point, strut crossing or inflow overlap is an uneven rearrangement of the end crowns of a self-expanding prosthetic heart valve stent frame beneath the capsule of the delivery device, which may occur during initial loading of the prosthetic heart valve. This phenomenon may cause the stent frame to infold during recapture or deployment. Infolding is a fold within the frame that is inward away from the anatomical structure and extends in a vertical line along the frame. Infolding may have short-term and long-term consequences.

[0009] Other aspects of the present disclosure relate to a system including a prosthetic heart valve and a delivery device. The prosthetic heart valve includes a stent frame and a valve structure. The stent frame can be transformed between a compressed state and an expanded state. The valve structure is supported by the stent frame. A first region of the stent frame extends longitudinally beyond the valve structure in a first direction, and a second region of the stent frame extends longitudinally beyond the valve structure in a second direction opposite to the first direction. The delivery device includes an outer shaft assembly and an inner shaft assembly. The outer shaft assembly includes a capsule extending distally from the outer shaft. The inner shaft assembly is coaxially received in the outer shaft assembly and includes an inner shaft, a valve retainer and a tubular support. The valve retainer is maintained by the inner shaft. The tubular support is assembled on the inner shaft and extends distally from the valve retainer. The system is configured to provide a delivery state in which the prosthetic heart valve is accommodated on the inner shaft assembly in a compressed state by the capsule, the first region of the stent frame is connected to the valve retainer, and at least a majority of the first region contacts the tubular support. In some embodiments, the tubular body minimizes or prevents crossing and / or infolding of struts along the first region, for example, when loading the prosthetic heart valve into a delivery device.

[0010] Other aspects of the present disclosure relate to a method for loading a prosthetic heart valve onto a delivery device. The prosthetic heart valve includes a stent frame and a valve structure. The stent frame is convertible between a compressed state and an expanded state. The valve structure is supported by the stent frame. A first region of the stent frame extends longitudinally beyond the valve structure in a first direction, and a second region of the stent frame extends longitudinally beyond the valve structure in a second direction opposite to the first direction. The method includes receiving a delivery device. The delivery device includes an outer shaft assembly and an inner shaft assembly. The outer shaft assembly includes a capsule extending distally from the outer shaft. The inner shaft assembly is coaxially received in the outer shaft assembly and includes an inner shaft, a valve retainer, and a terminal unit. The valve retainer is maintained by the inner shaft. The terminal unit extends distally from the inner shaft and defines a proximal segment, a distal segment opposite to the proximal segment, and an intermediate segment between the proximal segment and the distal segment. The outer diameter of the proximal segment is greater than the outer diameter of the inner shaft. The outer diameter of the intermediate segment is greater than the outer diameter of the proximal segment. The outer diameter of the tip unit increases at the transition from the middle section to the distal section. The method further includes arranging the delivery device and the prosthetic heart valve into a delivery state, in which the prosthetic heart valve is contained in a compressed state by the capsule over the inner shaft assembly, the first region of the stent frame is connected to the valve retainer, and at least a portion of the second region of the stent frame contacts the proximal section. In some embodiments, the arranging step includes folding the prosthetic heart valve over the inner shaft assembly. In some embodiments, the second region terminates in a plurality of crowns, and the arranging step is characterized in that the tip unit prevents the crowns from crossing each other. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1A is a side view of a prosthetic heart valve that may be used with the systems and delivery devices of the present disclosure and is in a normal, expanded state;

[0012] Figure 1B It is in a compressed state Figure 1A Side view of a prosthetic heart valve;

[0013] Figure 2 is an exploded perspective view of a delivery device according to the principles of the present disclosure;

[0014] Figure 3 is a simplified illustration of a system according to the principles of the present disclosure, the system comprising a Figure 2 Delivery device Figure 1A prosthetic heart valves;

[0015] Figure 4 yes Figure 2 An enlarged side view of a portion of a delivery device including an inner shaft and a tip unit;

[0016] Figure 5A and Figure 5BShown in simplified form is the Figure 4 The terminal unit Figure 1A prosthetic heart valves;

[0017] Figure 6 is with Figure 2 An enlarged side view of another end unit for use with a delivery device;

[0018] Figure 7 yes Figure 1B Prosthetic heart valves and Figure 2 A simplified side view of a delivery device of the invention, including a tubular support body and an inner shaft, when the portions thereof are juxtaposed;

[0019] Figure 8 A simplified representation of the delivery status Figure 2 of the system and shows Figure 1B Prosthetic heart valves relative to Figure 7 The arrangement of tubular supports; and

[0020] Fig. 9A and Fig. 9B A method of loading a prosthetic heart valve onto a delivery device according to the principles of the present disclosure is presented. DETAILED DESCRIPTION

[0021] Specific embodiments of the present disclosure will now be described with reference to the drawings, wherein like reference numbers indicate identical or functionally similar elements.

[0022] Aspects of the present disclosure are useful for use with prosthetic heart valves and heart valve repair methods including implanting prosthetic heart valves, particularly prosthetic heart valves delivered via transcatheter surgery. As mentioned herein, a prosthetic heart valve may include a bioprosthetic heart valve structure with tissue leaflets, or a synthetic heart valve with polymeric, metallic or tissue-engineered leaflets, and may be specifically configured to replace or repair a valve of a human heart. In a non-limiting example, the valve of a human heart is an aortic valve, but the systems and methods of the present disclosure may be used with a mitral valve, a tricuspid valve or a pulmonary heart valve. The prosthetic heart valve of the present disclosure may be self-expanding, balloon-expandable and / or mechanically expandable, or a combination thereof. In general, the prosthetic heart valve of the present disclosure includes a stent or stent frame having an inner cavity for maintaining a valve structure (tissue or synthetic), wherein the stent frame has a normal expanded state or arrangement, and may be folded to a compressed state or arrangement for loading in a delivery device. For example, stent or stent framework are supporting structures, and these supporting structures comprise many pillars or wire segments arranged relative to each other, thereby provide desired compressibility and strength for prosthetic valve. Pillar or wire segments are arranged so that they can automatically change into normal radial expansion arrangement or be forced to change into normal radial expansion arrangement from compression or folding arrangement. Pillar or wire segments can be formed by shape memory material alternatively, and this shape memory material is such as nickel titanium alloy (for example, nitinol). Stent framework can be formed by single piece material laser cutting, or can be assembled by multiple discrete components.

[0023] Considering the above understanding, Figure 1A A non-limiting example of a prosthetic heart valve 20 that may be used with the systems and methods of the present disclosure is shown in FIG. Figure 1A The views are shown in a normal or expanded state; Figure 1B A prosthetic heart valve 20 is shown in a compressed state (e.g., when compressed and retained within an outer catheter or sheath (not shown)). The prosthetic heart valve 20 includes a stent or stent frame 22 and a valve structure 24. The stent frame 22 can take any of the forms described above and is generally configured to be movable from a compressed position ( Figure 1B ) from expansion to normal expansion arrangement ( Figure 1A). In other embodiments, the stent frame 22 can be expanded to an expanded arrangement by a separate device (e.g., a balloon located inside the stent frame 22). The valve structure 24 is assembled to the stent frame 22 and provides two or more (typically three) leaflets 26a, 26b. The leaflets 26a, 26b (and other portions of the valve structure 24) can be formed from autologous tissue, xenograft material, or a synthetic material. The leaflets 26a, 26b can be provided as a homogeneous biological valve structure (such as a porcine, bovine, or equine valve). Alternatively, the leaflets 26a, 26b can be provided independently of each other (e.g., bovine or equine pericardial leaflets) and subsequently assembled to the stent frame 22. The valve structure 24 can be assembled to the stent frame 22 in various ways (e.g., by suturing the valve structure 24 to one or more struts or wire segments 28 defined by the stent frame 22). As will be appreciated by those of ordinary skill, the prosthetic heart valve 20 may include conventionally employed additional components, such as a skirt or similar structure.

[0024] exist Figure 1A and Figure 1B In the case of the example configuration of the prosthetic heart valve 20, the prosthetic heart valve 20 is configured to replace the aortic valve. Alternatively, other shapes suitable for the specific anatomical structure of the valve to be replaced are also envisioned (for example, the shape and / or size of the prosthetic heart valve according to the present disclosure can be alternatively designed to replace the native mitral valve, pulmonary valve or tricuspid valve). In any case, the valve structure 24 can be arranged to extend less than the entire length of the stent frame 22 to define a first zone 30 and a second zone 32 opposite to the first zone. The first zone 30 extends to the first end 34 of the stent frame 22, wherein a crown 36 is formed at the intersection of two (or more) adjacent wire segments in the wire segment 28. Similarly, the second zone 32 extends to the second end 38 of the stent frame 22, at which a crown 40 is formed. In some embodiments, the first zone 30 and the second zone 32 can be regarded as having no or no leaflets 26a, 26b or other fine structures of the prosthetic heart valve 20.

[0025] The construction and arrangement of the leaflets 26a, 26b define the direction of blood flow through the prosthetic heart valve 20, wherein the first zone 30 serves as the outflow zone or outflow side and the second zone 32 serves as the inflow zone or inflow side. The terms "inflow" and "outflow" may also refer to the arrangement of the prosthetic heart valve 20 relative to the native aortic valve (or other valve) being replaced when ultimately implanted. In embodiments where the prosthetic heart valve 20 is to be implanted via a retrograde approach, the prosthetic heart valve 20 will be arranged within a corresponding delivery device such that the inflow zone 30 is proximal to the outflow zone 32. With these conventions in mind, one or more connectors 42 (e.g., posts, tabs, etc.) are optionally formed or provided by the stent frame 22 at the first end 34 (i.e., the first zone or outflow zone 30), for example as an extension from a corresponding one of the crowns 36. The connector 42 (e.g., posts, tabs, etc.) is adapted to be connected to corresponding components of the delivery device, as described below. Although the stent frame 22 is Figure 1A and Figure 1B 4, but any other number (whether more or less) is equally acceptable. For example, the stent frame 22 may include as few as a single connector 42. In yet other embodiments, the connector 42 may be omitted.

[0026] Considering the above understanding of the prosthetic heart valve 20, Figure 2 An embodiment of a delivery device 50 according to the principles of the present disclosure is shown in FIG. The delivery device 50 includes an outer shaft assembly 52, an inner shaft assembly 54, and a handle 56. Figure 3 The delivery device 50 is combined with the prosthetic heart valve 20 to form a system 60 for restoring (e.g., replacing) a defective heart valve of a patient according to the principles of the present disclosure. The delivery device 50 is generally configured to deliver the prosthetic heart valve 20 in a compressed state percutaneously to a target site and deploy the prosthetic heart valve 20 at the target site. For example, the delivery device 50 provides a delivery state ( Figure 3 ), in the delivery state, the prosthetic heart valve 20 is connected to the valve retainer 70 of the inner shaft assembly 54 (in Figure 2 ), and is compressed and retained in the capsule 80 of the outer shaft assembly 52. ​​When defining the deployed state of the delivery device 50, the outer shaft assembly 52 can be moved by the handle assembly 56 (such as by Figure 3The inner shaft assembly 54 is manipulated to withdraw the capsule 80 proximally from the prosthetic heart valve 20 by operation of the inner shaft assembly 54 (schematically reflected). In the deployed state, withdrawing the capsule 80 allows the prosthesis 20 to self-expand (alternatively, causes the prosthesis to expand) and be released from the inner shaft assembly 54. Other features discussed below (where provided) can be operated to achieve such release. In any case, the inner shaft assembly 54 includes one or more features described below (such as the end unit 90 and / or the tubular support body 92) that support the prosthetic heart valve 20 during loading onto the inner shaft assembly 54 and when in the delivery state. The end unit 90 and / or the tubular support body 92 minimize or prevent crossing or folding inwards of the stent frame 22 at one or both of the first zone 30 and the second zone 32.

[0027] Figure 2 and Figure 3 The various features of components 52-56 reflected in and described below may be modified or replaced with different structures or mechanisms. Therefore, the present disclosure is in no way limited to the outer shaft assembly 52, inner shaft assembly 54, handle assembly 56, etc. as shown and described below. More generally, then, some delivery devices according to the principles of the present disclosure provide features (e.g., capsule 80) that can retain a self-expanding stented prosthetic heart valve, and one or more components (e.g., tip unit 90 and / or tubular support body 92) that can support the prosthetic heart valve when the prosthetic heart valve is compressed or folded over the inner shaft assembly 54.

[0028] In some embodiments, the outer shaft assembly 52 includes a capsule 80 and a shaft 100, and defines a proximal end 102 and a distal end 104. A lumen 106 is formed by the outer shaft assembly 52 (in Figure 3), which extends from a distal end 104 through the capsule 80 and at least a portion of the shaft 100. The lumen 106 can be open at the proximal end 102. The capsule 80 extends distally from the shaft 100 and, in some embodiments, has a stiffer construction (compared to the stiffness of the shaft 80) that exhibits a radial or circumferential stiffness sufficient to fully resist the expected expansion force of the prosthetic heart valve 20 when compressed within the capsule 80. For example, the shaft 100 can be a polymer tube embedded with a metal braid, and the capsule 80 can include a laser-cut metal tube optionally embedded in a polymer covering. Alternatively, the capsule 80 and the shaft 100 can have a more uniform construction (e.g., a continuous polymer tube). In any case, the capsule 80 is configured so that the stented prosthetic heart valve 20 is compressed and retained at a predetermined diameter when loaded within the capsule 80, and the shaft 100 is used to connect the capsule 80 to the handle assembly 56. The shaft 100 (and the capsule 80) is configured to be sufficiently flexible to pass through the vasculature of a patient, yet exhibit sufficient longitudinal stiffness to achieve desired axial movement of the capsule 80. In other words, proximal retraction of the shaft 100 is directly transmitted to the capsule 80 and causes a corresponding proximal retraction of the capsule 80. In other embodiments, the shaft 100 is further configured to transmit a user-generated rotational force or rotational movement to the capsule 80.

[0029] The inner shaft assembly 54 can have various configurations for supporting the prosthetic heart valve 20. The inner shaft assembly 54 is sized and shaped to extend within the central lumen 106 of the outer shaft assembly 52. ​​The inner shaft assembly 54 includes an inner shaft 110, a valve retainer 70, a distal tip (e.g., provided by an optional tip unit 90), and an optional tubular support 92. The inner shaft 110 is sized to be slidably received within the lumen 106 of the outer shaft assembly 52, and is configured to mount the valve retainer 70, the tip unit 90, and the tubular support 92 (where provided). Figure 2 As shown, the inner shaft 110 can include a distal section 112 and a proximal section 114. The distal section 112 terminates at a distal end 116 and connects the tip unit 90 to the proximal section 114. The proximal section 114 in turn couples the inner shaft assembly 54 to the handle assembly 56. The inner shaft 110 can define a continuous lumen (hidden) sized to slidably receive an auxiliary component, such as a guidewire (not shown).

[0030] The distal segment 112 may be a flexible polymer tube embedded with a metal braid. Other configurations are also acceptable, as long as the distal segment 112 exhibits sufficient structural integrity to support the loaded compression prosthetic heart valve. In some configurations, the proximal segment 114 may include a front portion 120 and a rear portion 122. The front portion 120 serves as a transition between the distal segment 112 and the proximal segment 114, and is therefore a flexible polymer tube (e.g., PEEK) in some embodiments, the outer diameter of the flexible polymer tube being slightly smaller than the outer diameter of the distal segment 112. The rear portion 122 may have a more rigid configuration (e.g., a metal hypotube) that is suitable for secure assembly with the handle assembly 56. Other materials and configurations are also contemplated. For example, in an alternative embodiment, the distal segment 112 and the proximal segment 114 are integrally formed into a single homogeneous tube or solid shaft.

[0031] The valve retainer 70 can take a variety of forms suitable for selectively capturing or connecting to corresponding features of the prosthetic heart valve 20. Figure 1A and Figure 1B In some embodiments where the prosthetic heart valve 20 includes a connector 42, the valve retainer 70 may include or define grooves that are sized and shaped to receive corresponding connectors in the connector 42. For example, the valve retainer 70 may be a hub or spindle having (multiple) grooves formed therein. Other configurations are also acceptable. Further, the inner shaft assembly 54 may optionally include additional components or mechanisms that assist in temporarily securing corresponding features of the prosthetic heart valve 20 to the valve retainer 70 and / or in releasing the prosthetic heart valve 20 from the valve retainer 70 when the capsule 80 is fully retracted. In any event, in the delivery state, the length of the prosthetic heart valve 20 (in the folded state) is effectively predetermined. Therefore, because the position of the end of the prosthetic heart valve 20 that is secured to the valve retainer 70 is predetermined, the position of the opposite end of the prosthetic heart valve 20 relative to the delivery device 50 is also effectively predetermined. For example, in Figure 3 In the embodiment of the present invention, first end 34 is fixed to valve retainer 70; when prosthetic heart valve 20 is in the folded state, the longitudinal position of second region 32, and in particular second end 38, relative to other components of delivery device 50 (e.g., relative to tip unit 90) is also essentially predetermined. In some embodiments, tip unit 90 includes features configured to support second region 32 at or near this essentially predetermined position, as described below.

[0032] Considering the above, Figure 4 One embodiment of the terminal unit 90 is shown in more detail in FIG. Figure 4As shown, in final assembly, the tip unit 90 extends distally from the inner shaft 110. The shape or contour of the tip unit 90 defines a proximal section 120, an intermediate section 122, and a distal section 124. The intermediate section 122 extends between the proximal section 120 and the distal section 124. The outer diameter OD of the proximal section 120 is P Greater than the outer diameter OD of the inner shaft 110 (at least along the section of the inner shaft 90 immediately adjacent to the end unit 90) S The outer diameter OD of the middle section 122 is I Greater than the outer diameter OD of the proximal section 120 P The outer diameter of the tip unit 90 increases at the transition from the intermediate section 122 to the distal section 124, for example, to a maximum distal section outer diameter OD D Finally, the distal section 124 can define a distally tapered outer profile extending from the intermediate section 122 to the tip end 126 that is suitable, for example, for promoting atraumatic contact with body tissue.

[0033] In some embodiments, the outer diameter OD of the proximal segment 120 is P The corresponding area ( Figure 1A and Figure 1B ), for example to minimize the tendency of the prosthetic heart valve 20 to cross or overlap its struts. For example, Figure 5A A simplified representation of a portion of the stent frame 22 that has been collapsed over the inner shaft 110 to a folded state (ie, delivery state) is shown. Figure 3 The capsule 80 is omitted in the view of Figure 2 ), it should be understood that the capsule 80 constrains the stent frame 22 in the folded state ( Figure 3 ). It will be recalled that, in the delivery state, the position of the second region 32 of the stent framework 22 relative to the tip unit 90 is essentially predetermined. With this in mind, the tip unit 90 is positioned such that the proximal section 120 is positioned radially aligned with or radially inward of at least a portion of the second region 32 proximal to the second end 38. Although Figure 5A The second end 38 is shown aligned with the proximal section 120 , but in other embodiments, the second end 38 may be positioned along or aligned with the intermediate section 122 .

[0034] Figure 5AGenerally, it is reflected that, in the delivery state, a portion of the second region 32 is folded or folded into contact with the surface of the proximal section 120 of the tip unit 90. In other arrangements, there may be a slight radial gap between the second region 32 and the surface of the proximal section 120. In any case, the portion of the second region 30 near the second end 38 is aligned with the proximal section 120, where the outer diameter OD of the proximal section 120 is greater than the outer diameter OD of the proximal section 120. P Greater than the outer diameter OD of the inner shaft 110 S The proximal section 120 provides a support for the second region 32 (eg, the struts 28 and crowns 40 ( Figure 1A and Figure 1B In other words, without the proximal segment 120, the second end 38 and the remainder of the second region 32 may be free to deflect radially inwardly toward the inner shaft 110 in a manner that may otherwise have a tendency to allow the struts 28 and / or crowns 40 to undesirably overlap or cross along the second region 32. The support provided by the proximal segment 120 minimizes or prevents the struts from crossing or overlapping along the second region 32 near the first end 38.

[0035] The end unit 90 may include or exhibit additional beneficial profile features. For example, additional reference Figure 4 In some embodiments, the middle section 122 can be shaped to define a rear section 130 and a front section 132. The rear section 130 extends from the proximal section 120 to the front section 132, and the front section 132 extends from the rear section 130 to the distal section 124. With these definitions in mind, in some embodiments, the rear section 130 defines a smooth, continuously expanding outer diameter from the proximal section 120 to the front section 132. With this smooth, continuously expanding diameter profile or shape, the second end 38 can easily slide along the rear section 130 (compared to a shape with a steeper edge or shoulder formed at the transition from the proximal section 120 to the middle section 122). Therefore, when the delivery device 50 ( Figure 2 ) is manipulated through tortuous anatomical structures, so as to minimize potential damage to the stent frame 22.

[0036] The front section 132 can have a substantially uniform outer diameter (ie, within 5% of a truly uniform outer diameter) as it extends from the rear section 130 to the distal section 124. Using these and other configurations, the intermediate section 122 is configured to receive and support the capsule 80, such as Figure 5B As shown in the figure, in the delivery state, the distal end 104 of the capsule 80 can be located along the middle section 122 and adjacent to the distal section 124. In some embodiments, the maximum distal section outer diameter OD of the distal section 124 is D( Figure 4 ) may approximate the outer diameter of the capsule 80 at the distal end 104. In any case, Figure 5B This reflects that the proximal segment 120 effectively increases the packing density inside the capsule 80 (compared to the packing density without the proximal segment 120). This increased packing density is used to minimize or prevent the struts 28 and crowns 40 ( Figure 1A and Figure 1B ) are folded over each other.

[0037] In the illustrated and described embodiment, the header unit 90 is formed as a homogeneous, unitary body (e.g., a molded polymer body). In other embodiments, the header unit 90 may be formed or defined by two (or more) separately formed bodies. For example, Figure 6 Another embodiment of a tip unit 90' assembled to the inner shaft 110 is shown. The tip unit 90' includes a first or support body 140 and a second or tip body 142. The first body 140 and the second body 142 are formed separately and assembled to the inner shaft 110 in various ways. For example, the first body 140 and the second body 142 can be fixed to each other by threading, compression, snap fit, overmolding, etc. In other embodiments, the first body 140 and the second body 142 do not necessarily need to be physically fixed or attached to each other, but can be arranged in an adjacent relationship when assembled to the inner shaft 110. In some embodiments, the first body 140 is configured and arranged to define the proximal section 120 as described above, and the second body 142 is configured and arranged to define the middle section 122 and the distal section 124. The first body 140 and the second body 142 can be formed of the same or different materials. For example, the second body 142 can be a molded polymer conventionally used for transcatheter prosthetic heart valve delivery devices. The first body 140 may be formed of a more flexible material (eg, a soft or elastic polymer ring or tube). In any case, the end unit 90' provides a similar configuration to the end unit 90 ( Figure 5A ) same or similar features, including in the prosthetic heart valve 20 ( Figure 1A ) during (and after) loading of the proximal section 120 to minimize or prevent strut crossing or overlapping.

[0038] return Figure 2 and Figure 3 Where provided, the tubular support body 92 can help minimize or prevent infolding or crossing at the first end 34 of the stent framework 22. Figure 7, the tubular support 92 can be formed of a material suitable for contacting the prosthetic heart valve 20. As shown, the tubular support 92 is assembled on the inner shaft 110 adjacent to the valve retainer 70 and extends distally from the valve retainer 70. The outer diameter of the tubular support 92 is greater than the outer diameter of the inner shaft 110, wherein the tubular support 92 thus provides a surface for supporting the prosthetic heart valve 20 during and after loading, as described below. In some embodiments, the length of the tubular support 92 or the distal extension of the tubular support 92 relative to the valve retainer 70 is selected based on the expected position of one or more components of the prosthetic heart valve 20 when loaded into the delivery device 20, while maximizing the length of the support provided to the stent frame 22.

[0039] For example, upon final assembly, the tubular support body 92 terminates at a distal side 150 opposite the valve retainer 70. The length and position of the tubular support body 92 are selected so that the distal side 150 of the tubular support body 92 is proximally spaced from the delicate structures of the prosthetic heart valve 20 (e.g., the valve structure 24, particularly the leaflets 26a, 26b) during loading. With this structure, the leaflets 26a, 26b do not contact the tubular support body 92 during loading, which may otherwise damage the leaflets 26a, 26b. By way of further explanation, it will be recalled that in the delivery state, the first end 34 of the stent frame 22 is connected to the valve retainer 70, for example, via the connector 42. Therefore, the longitudinal distance from the connector 42 to the leaflets 26a, 26b in the folded state is essentially predetermined. The length of the tubular support 92 and / or the longitudinal distance from the valve retainer 70 to the distal side 150 can be selected based on this essentially predetermined dimension of the prosthetic heart valve 20 . Figure 7 The prosthetic heart valve 20 is shown in a folded state, separated from the delivery device 50, but aligned with the longitudinal position when loaded onto the inner shaft 110. With this in mind, the tubular support 92 is configured and arranged to position the distal end 150 a sufficient distance proximal to the leaflets 26a, 26b to ensure that the leaflets 26a, 26b (and potentially other portions of the valve structure 24 and / or other delicate surfaces of the prosthetic heart valve 20) do not contact the tubular support 92 during and after loading. In addition to this design parameter, the tubular support 92 can extend beyond the valve retainer 70 to provide substantial support for the stent frame 22.

[0040] exist Figure 8 FIG. 1 shows in simplified form an acceptable arrangement of the tubular support body 92 relative to the prosthetic heart valve 20 in the delivery state (for simplicity of illustration, the outer shaft assembly 52 is omitted from the view). Figure 2)). The first end 34 of the stent frame 22 is connected to the valve retainer 70. The stent frame 22 is creased or folded along a portion of the first region 30 to contact the surface of the tubular support body 92. In other arrangements, there may be a slight radial gap between the stent frame 22 and the tubular support body 92. In any case, the portion of the first region 30 proximal to the first end 34 is aligned with the tubular support body 92 or disposed radially outside the tubular support body, wherein the tubular support body 92 provides support for the first region 30 (e.g., the struts 28 and crowns 36 ( Figure 1A and Figure 1B )). In other words, in the absence of the tubular support body 92, the portion of the stent frame 22 along the first zone 30 can be free to deflect radially inward toward the inner axis 110, and its deflection manner may additionally have a tendency to allow the struts 28 to overlap or cross undesirably along the first zone 30. The support provided by the tubular support body 92 minimizes or prevents the struts from crossing or overlapping along the first zone 30. The distal end 150 is proximally spaced from the leaflets 26a, 26b (and in some embodiments, from other portions of the valve structure 24) such that the leaflets 26a, 26b do not contact the tubular support body 92. However, in some embodiments, the tubular support body 92 is sized and positioned to extend along a significant length of the first zone 30 and may be in contact therewith. For example, in some embodiments, the tubular support body 92 is radially aligned with or arranged radially inward of at least a majority of the length of the first zone 30 (e.g., the length of the tubular support body 92 is at least 50% of the longitudinal length from the first end 34 of the prosthetic heart valve 20 in a compressed state to the leaflets 26a, 26b).

[0041] return Figure 2 , the handle assembly 56 can take various forms suitable for user manipulation and operation of the delivery device 50. In some embodiments, the handle assembly 56 includes a housing 160 and one or more actuator mechanisms 162 (generally labeled). The housing 160 generally provides a surface that is convenient for user manipulation and gripping, and can have a generally cylindrical shape as shown, but other shapes and sizes are also acceptable. The housing 160 retains the actuator mechanism 162, wherein the handle assembly 56 is configured to facilitate sliding movement of the outer shaft assembly 52 relative to the inner shaft assembly 54 (and / or sliding movement of the inner shaft assembly relative to the outer shaft assembly). In a simplified construction of the actuator mechanism 162, the user interface or actuator 164 is slidably held by the housing 160 and connected to the proximal end 102 of the outer shaft assembly 52. ​​The proximal end of the inner shaft assembly 54 is fixed to the housing 160. With this optional construction, the sliding movement of the actuator 164 causes the outer shaft assembly 52 to advance / retract coaxially relative to the inner shaft assembly 54, such as Figure 3 . Although shown as a sliding mechanism, other configurations and / or devices may be used to retract / advance the outer shaft assembly 52 relative to the inner shaft assembly 54 (and / or retract / advance the inner shaft assembly relative to the outer shaft assembly), such as but not limited to a rotating mechanism, a sliding mechanism coaxially disposed on the inner shaft assembly 54, a combination of a rotating mechanism and a sliding mechanism, and other advancement / retraction mechanisms apparent to those of ordinary skill in the art. The handle assembly 56 may optionally include one or more additional components or mechanisms.

[0042] The prosthetic heart valve 20 can be loaded into the delivery device 50 in a variety of different ways and optionally with the aid of one or more tools. Generally speaking, the prosthetic heart valve 20 is arranged on the inner shaft 110 with the outer shaft assembly 52 retracted relative to the inner shaft assembly 54 to position the capsule 80 proximal to the valve retainer 70. At this initial stage, portions of the prosthetic heart valve 20 may or may not be partially or completely collapsed toward the folded state. In any case, reference is made to Fig. 9A The first end 34 of the stent frame 22 is connected to the connector 42 ( Figure 1A and Figure 1B ) is connected to the valve retainer 70. The capsule 80 is advanced distally over the prosthetic heart valve 20, wherein the portion of the prosthetic heart valve 20 within the capsule 80 is collapsed and maintained in a folded state by the capsule. Fig. 9A In the loading stage shown, the capsule 80 has been gradually advanced to surround the first region 30, so that the first region 30 is maintained in a folded state; the portion of the prosthetic heart valve 20 distal to the capsule 80 may or may not be partially folded or collapsed. In any case, in an optional embodiment where the delivery device 50 includes a tubular support 92, when the first region 30 is collapsed and contained within the capsule 80, the struts 28 and / or crowns 36 (for example, near the first end 34) along the first region 30 (for example, Figure 1A and Figure 1B ) can be oriented radially inward and in contact with the tubular support body 92; in these cases, the presence of the tubular support body 92 minimizes the chance of the struts 28 and / or crowns 36 so oriented folding inward and / or crossing over each other and in some embodiments prevents such folding inward and / or crossing over each other.

[0043] Fig. 9B 8. A later stage of the loading process is shown. The capsule 80 has been further advanced distally to surround the second region 32, such that the second region 32 is maintained in a folded state. When the second region 32 is collapsed and contained within the capsule 80, the struts 28 and / or crowns 40 (eg, near the second end 38) along the second region 32 are Figure 1A and Figure 1B) can be oriented radially inward and in contact with the proximal segment 120 of the end unit 90; in these cases, the presence of the proximal segment 120 minimizes the chance of the struts 28 and / or crowns 40 so oriented folding inward and / or crossing over each other and in some embodiments prevents such folding inward and / or crossing over each other.

[0044] The transcatheter prosthetic heart valve delivery devices and systems of the present disclosure provide significant improvements over previous designs. Compared to conventional designs, the delivery devices of the present disclosure provide additional support to one or both end regions of the prosthetic heart valve during and after loading, thereby minimizing or preventing strut and / or crown crossing or infolding.

[0045] Although the present disclosure has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the present disclosure.

Claims

1. A system comprising: A prosthetic heart valve, the prosthetic heart valve comprising: a stent frame, the stent frame being transitionable between a compressed state and an expanded state, a valve structure, the valve structure being supported by the stent frame, wherein a first region of the stent frame extends longitudinally beyond the valve structure in a first direction, and a second region of the stent frame extends longitudinally beyond the valve structure in a second direction opposite to the first direction; and A delivery device, the delivery device comprising: an outer shaft assembly including a capsule extending distally from the outer shaft, an inner shaft assembly, the inner shaft assembly being coaxially received within the outer shaft assembly, the inner shaft assembly comprising: Inner shaft, a valve retainer, the valve retainer being maintained by the inner shaft; a tip unit extending distally from the inner shaft, the tip unit defining a proximal section, a distal section opposite the proximal section, and an intermediate section between the proximal section and the distal section, in: The outer diameter of the proximal section is greater than the outer diameter of the inner shaft, The outer diameter of the intermediate section is greater than the outer diameter of the proximal section, The outer diameter of the tip unit increases at a transition from the middle section to the distal section; wherein the system is configured to provide a delivery state in which the prosthetic heart valve is contained by the capsule in the compressed state on the inner shaft assembly, a first region of the stent frame is connected to the valve retaining member, and at least a portion of a second region of the stent frame contacts the proximal segment.

2. The system of claim 1, wherein: The capsule terminates at a distal end, and further wherein the delivery state includes the distal end being disposed above the intermediate section.

3. The system of claim 1, wherein: The distal section defines a tapered outer diameter extending from the intermediate section to a distal end of the header unit.

4. The system of claim 1, wherein: The intermediate section defines a rear section extending from the proximal section and a front section extending from the rear section to the distal section, and further wherein the rear section defines an expanded outer diameter from the proximal section to the front section.

5. The system of claim 4, wherein: The anterior segment defines a substantially uniform diameter extending from the posterior segment to the distal segment.

6. The system of claim 1, wherein: The head unit is a one-piece homogeneous body fixed to the inner shaft.

7. The system of claim 1, wherein: The terminal unit comprises: a tip body defining the intermediate section and the distal section; and A support body is disposed separately from the tip body and defines the proximal section.

8. The system of claim 7, wherein: The tip body and the support body are made of different materials.

9. The system of claim 1, wherein: The inner shaft assembly further includes a tubular support assembled over the inner shaft and extending distally from the valve retainer.

10. The system of claim 9, wherein: The delivery state further comprises at least a portion of the first region of the stent framework being in contact with the tubular support.

11. A system comprising: A prosthetic heart valve, the prosthetic heart valve comprising: a stent frame, the stent frame being transitionable between a compressed state and an expanded state, a valve structure, the valve structure being supported by the stent frame, wherein a first region of the stent frame extends longitudinally beyond the valve structure in a first direction, and a second region of the stent frame extends longitudinally beyond the valve structure in a second direction opposite to the first direction; and A delivery device, the delivery device comprising: an outer shaft assembly including a capsule extending distally from the outer shaft, an inner shaft assembly, the inner shaft assembly being coaxially received within the outer shaft assembly, the inner shaft assembly comprising: Inner shaft, a valve retainer, the valve retainer being maintained by the inner shaft; a tubular support assembled over the inner shaft and extending distally from the valve holder; wherein the system is configured to provide a delivery state in which the prosthetic heart valve is contained by the sac in the compressed state on the inner shaft assembly, a first region of the stent frame is connected to the valve retaining member, and at least a majority of the first region contacts the tubular support body.

12. The system of claim 11, wherein: The inner shaft assembly further includes a tip unit extending distally from the inner shaft, the tip unit defining a proximal section, a distal section opposite the proximal section, and an intermediate section between the proximal section and the distal section.

13. The system of claim 12, wherein: The delivery state further includes at least a portion of the second region being in contact with the proximal segment.

14. The system of claim 13, wherein: The outer diameter of the proximal section is greater than the outer diameter of the inner shaft; The outer diameter of the intermediate section is greater than the outer diameter of the proximal section; and The outer diameter of the tip unit increases at the transition from the intermediate section to the distal section.

15. The system of claim 11, wherein: The valve structure is configured and arranged relative to the stent frame such that the first region is an outflow region and the second region is an inflow region.

16. A method of loading a prosthetic heart valve onto a delivery device, the prosthetic heart valve comprising a stent frame capable of transitioning between a compressed state and an expanded state, and a valve structure supported by the stent frame, wherein: The first region of the stent frame extends longitudinally beyond the valve structure in a first direction, and the second region of the stent frame extends longitudinally beyond the valve structure in a second direction opposite to the first direction, the method comprising: receiving a delivery device, the delivery device comprising: an outer shaft assembly including a capsule extending distally from the outer shaft, an inner shaft assembly, the inner shaft assembly being coaxially received within the outer shaft assembly, the inner shaft assembly comprising: Inner shaft, a valve retainer, the valve retainer being maintained by the inner shaft; a tip unit extending distally from the inner shaft, the tip unit defining a proximal section, a distal section opposite the proximal section, and an intermediate section between the proximal section and the distal section, in: The outer diameter of the proximal section is greater than the outer diameter of the inner shaft, The outer diameter of the intermediate section is greater than the outer diameter of the proximal section, The outer diameter of the tip increases at a transition from the intermediate section to the distal section; and The delivery device and the prosthetic heart valve are arranged in a delivery state, in which the prosthetic heart valve is contained by the capsule in the compressed state on the inner shaft assembly, the first region of the stent frame is connected to the valve retaining member, and at least a portion of the second region of the stent frame contacts the proximal segment.

17. The method of claim 16, wherein: The deploying step includes creasing the prosthetic heart valve over the inner shaft assembly.

18. The method of claim 17, wherein: The second region terminates in a plurality of crowns, and further wherein the arranging step is characterized by the head unit preventing the crowns from crossing over one another.

19. The method of claim 16, wherein: The inner shaft assembly further includes a tubular support assembled over the inner shaft and extending distally from the valve retainer, and further wherein the delivery state includes at least a portion of the first region of the stent frame in contact with the tubular support.

20. The method of claim 19, wherein: The first region terminates in a plurality of crowns, and further wherein the arranging step is characterized by the tubular support preventing the crowns from crossing over one another.

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