WO2025090728A1

WO2025090728A1 - Delivery apparatus for prosthetic heart valve

Info

Publication number: WO2025090728A1
Application number: PCT/US2024/052755
Authority: WO
Inventors: Beatriz TAPIA; Sean Chow; Grant Jason GANGENESS; Izaak ROSEN; Camille Lazaro VILLADOLID
Original assignee: Edwards Lifesciences Corp
Current assignee: Edwards Lifesciences Corp
Priority date: 2023-10-25
Filing date: 2024-10-24
Publication date: 2025-05-01
Anticipated expiration: 2026-04-25

Abstract

A delivery apparatus configured to deliver a prosthetic valve can include a handle, a first and second shaft extending distally from the handle, the first shaft extending through a lumen of the second shaft, and a balloon mounted along the distal end portion of the first shaft. A distal end of the second shaft has a plurality of flexible arms which extend over the proximal end portion of the balloon and a plurality of tension members, each tension member with a distal end that is fixed relative to one of the plurality of flexible arms.

Description

DELIVERY APPARATUS FOR PROSTHETIC HEART VALVE

CROSS REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63/593,151, filed October 25, 2023, which is incorporated herein by reference.

FIELD

[0002] The present disclosure concerns delivery apparatuses, systems, and methods for implantation of a prosthetic valve.

BACKGROUND

[0003] The human heart can suffer from various valvular diseases. These valvular diseases can result in significant malfunctioning of the heart and ultimately require repair of the native valve or replacement of the native valve with an artificial valve. There are a number of known repair devices (for example, stents) and artificial valves, as well as a number of known methods of implanting these devices and valves in humans. Percutaneous and minimally-invasive surgical approaches are used in various procedures to deliver prosthetic medical devices to locations inside the body that are not readily accessible by surgery or where access without surgery is desirable. In one specific example, a prosthetic heart valve can be mounted in a crimped state on the distal end of a delivery apparatus and advanced through the patient’s vasculature (for example, through a femoral artery and the aorta) until the prosthetic heart valve reaches the implantation site in the heart. The prosthetic heart valve is then expanded to its functional size, for example, by inflating a balloon on which the prosthetic valve is mounted, actuating a mechanical actuator that applies an expansion force to the prosthetic heart valve, or by deploying the prosthetic heart valve from a sheath of the delivery apparatus so that the prosthetic heart valve can self-expand to its functional size. Operating a delivery apparatus for implantation of a prosthetic heart valve involves complex steps and requires specialized skills. Accordingly, improvements to known transcatheter delivery apparatuses to facilitate their operation are desirable.

SUMMARY

[0004] Described herein are systems and methods for delivering prosthetic devices, such as prosthetic heart valves, through the body and into an implant site, such as the heart, for implantation therein. The prosthetic devices delivered with the delivery systems disclosed herein are, for example, radially expandable from a radially compressed state mounted on the delivery system to a radially expanded state for implantation using an inflatable balloon (or equivalent expansion device) of the delivery system. Exemplary delivery routes through the body and into the heart include transfemoral routes, transapical routes, and transaortic routes, among others. Although the devices and methods disclosed herein are particularly suited for implanting prosthetic heart valves (for example, a prosthetic aortic valve or prosthetic mitral valve), the disclosed devices and methods can be adapted for implanting other types of prosthetic valves within the body (for example, prosthetic venous valves) or other types of expandable prosthetic devices adapted to be implanted in various body lumens.

[0005] In some examples, a delivery apparatus for a prosthetic implant can comprise a handle and one or more shafts coupled to the handle. In addition to these components, a delivery apparatus can further comprise one or more of the components disclosed herein. [0006] In some examples, a delivery apparatus can comprise a second shaft extending distally from the handle and a first shafting extending through a lumen of the first shaft. [0007] In some examples, the distal end portion of the second shaft can further include a plurality of flexible arms which extend over the proximal end portion of the balloon, wherein the arms are configured to flex radially outwardly from a longitudinal axis of the delivery apparatus upon inflation of the balloon.

[0008] In some examples, the plurality of flexible arms comprises two or more arms. In some examples, the plurality of flexible arms comprises five or more flexible arms. In some examples, the flexible arms extend over at least 10% of a length of the balloon. In some examples, the flexible arms extend over at least 25% of a length of the balloon. In some examples, the flexible arms have a length of least 8 mm.

[0009] In some examples, the delivery apparatus comprises a plurality of tension members, each tension member having a distal end that is fixed relative to one of the plurality of flexible arms. In some examples, the tension members comprise wires.

[0010] In some examples, the tension members are configured to flex the arms radially outwardly from a longitudinal axis of the delivery apparatus when tension on the tension members is increased. In some examples, the tension members are configured to flex the arms radially away from an outer surface of the balloon when the tension on the tension members is increased. [0011] In some examples, the tension applied to at least one of the tension members can be adjusted independent of the tension applied to the other tension members. In some examples, the tension applied to each tension member can be adjusted independent of each other.

[0012] In some examples, there is a handle coupled to the proximal end portion of the second shaft and the proximal end portions of the tension members, wherein the handle comprises a control mechanism configured to adjust the tension in the tension members. In some examples, the control mechanism is a knob configured to apply tension to the tension members when the knob is rotated.

[0013] In some examples, when the balloon is in a non-inflated state, the flexible arms are in an unexpanded state in which each flexible arm is in contact with two adjacent flexible arms. In other examples, when the balloon is on a non-inflated state, the flexible arms are in an unexpanded state in which the flexible arms are spaced apart from each other in a circumferential direction.

[0014] In some examples, the delivery apparatus is combined with an expandable medical implant in a radially compressed state disposed around the inflatable balloon. In some examples, the expandable medical implant is a prosthetic heart valve comprising an expandable stent and a leaflet structure supported by the stent.

[0015] In some examples, the distal ends of the flexible arms contact the proximal end of the expandable medical implant. In some examples, the distal ends of the flexible arms apply an axial force to the proximal end of the medical implant.

[0016] In some examples, the delivery device can be used to deliver and implant an implantable medical device, such as a prosthetic heart valve. An implantation procedure can include advancing the distal end portion of the delivery device towards the implant location until the medical implant is within or adjacent to the desired implant position, and inflating the balloon to cause the medical implant to radially expand to cause the plurality of longitudinally extending flexible arms to passively expand. Additionally, in some examples, when the delivery device includes tension members, tensioning the tension members causes the flexible arms to bend outward away from the balloon.

[0017] The above method(s) can be performed on a living animal or on a simulation, such as on a cadaver, cadaver heart, anthropomorphic ghost, simulator (e.g., with body parts, heart, tissue, etc. being simulated). [0018] The foregoing and other objects, features, and advantages of the invention will become more apparent from the following detailed description, which proceeds with reference to the accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] FIG. 1 is a side view of a delivery apparatus for implanting a prosthetic heart valve, according to one example.

[0020] FIG. 2A is a cross-sectional view of the handle of the delivery apparatus of FIG. 1.

[0021] FIG. 2B is another cross-sectional view of the handle of the delivery apparatus of FIG. 1.

[0022] FIG. 3 is side view of a section of the handle and a section of the distal end portion of the delivery apparatus of FIG. 1.

[0023] FIG. 4 is a side view of the distal end portion of the delivery apparatus of FIG. 1.

[0024] FIG. 5 is a side cross-sectional view of the distal end portion of the delivery apparatus of FIG. 1 showing the balloon in an inflated state.

[0025] FIG. 6 is an enlarged perspective view of a collet used in the handle of the delivery apparatus of FIG. 1.

[0026] FIG. 7 is a cross-sectional view of the collet of FIG. 6.

[0027] FIG. 8 is an enlarged side view of a mounting member for a prosthetic heart valve.

[0028] FIGS. 9-11 are enlarged, cross-sectional views of the distal end portion of the delivery apparatus of FIG. 1 , showing the inflation of a balloon for deployment of a prosthetic heart valve on the balloon.

[0029] FIG. 12 depicts a side view of a delivery apparatus with an uninflated balloon and flexible arms in an unexpanded state, according to another example.

[0030] FIG. 13 depicts a side view of a distal end portion of the delivery apparatus of FIG.

12 showing the balloon partially inflated and the flexible arms in a passively expanded position.

[0031] FIG. 14 depicts a side view of the distal end portion of the delivery apparatus FIG. 12 showing the balloon in a fully inflated state and the flexible arms being further expanded by operation of the tension members.

[0032] FIG. 15 depicts alignment of a prosthetic valve mounted on a balloon of a delivery apparatus with an aortic annulus, according to one example. [0033] FIG. 16 depicts an example of a prosthetic heart valve that can be implanted using any of the delivery apparatuses disclosed herein.

DETAILED DESCRIPTION

General Considerations

[0034] It should be understood that the disclosed examples of delivery apparatuses can be adapted to deliver and implant prosthetic heart valves in any of the native annuluses of the heart (for example, the pulmonary, mitral, and tricuspid annuluses), and can be used with any of various delivery approaches (for example, retrograde, antegrade, transseptal, transventricular, transatrial, etc.).

[0035] For purposes of this description, certain aspects, advantages, and novel features of the examples of this disclosure are described herein. The disclosed methods, apparatus, and systems should not be construed as being limiting in any way. Instead, the present disclosure is directed toward all novel and nonobvious features and aspects of the various disclosed examples, alone and in various combinations and sub-combinations with one another. The methods, apparatus, and systems are not limited to any specific aspect or feature or combination thereof, nor do the disclosed examples require that any one or more specific advantages be present or problems be solved. The technologies from any example can be combined with the technologies described in any one or more of the other examples. In view of the many possible examples to which the principles of the disclosed technology may be applied, it should be recognized that the illustrated examples are only preferred examples and should not be taken as limiting the scope of the disclosed technology.

[0036] Although the operations of some of the disclosed examples are described in a particular, sequential order for convenient presentation, it should be understood that this manner of description encompasses rearrangement, unless a particular ordering is required by specific language set forth below. For example, operations described sequentially may in some cases be rearranged or performed concurrently. Moreover, for the sake of simplicity, the attached figures may not show the various ways in which the disclosed methods can be used in conjunction with other methods. Additionally, the description sometimes uses terms like “provide” or “achieve” to describe the disclosed methods. These terms are high-level abstractions of the actual operations that are performed. The actual operations that correspond to these terms may vary depending on the particular implementation and are readily discernible by one of ordinary skill in the art. [0037] As used in this application and in the claims, the singular forms “a,” “an,” and “the” include the plural forms unless the context clearly dictates otherwise. Additionally, the term “includes” means “comprises.” Further, the terms “coupled” and “connected” generally mean electrically, electromagnetically, and/or physically (for example, mechanically or chemically) coupled or linked and does not exclude the presence of intermediate elements between the coupled or associated items absent specific contrary language.

[0038] As used herein, the term “proximal” refers to a position, direction, or portion of a device that is closer to the user and further away from the implantation site. As used herein, the term “distal” refers to a position, direction, or portion of a device that is further away from the user and closer to the implantation site. Thus, for example, proximal motion of a device is motion of the device away from the implantation site and toward the user (for example, out of the patient’s body), while distal motion of the device is motion of the device away from the user and toward the implantation site (for example, into the patient’s body). The terms “longitudinal” and “axial” refer to an axis extending in the proximal and distal directions, unless otherwise expressly defined.

[0039] As used herein, the term “inflow” generally refers to a position, direction, or portion of the prosthetic heart valve that is closer to an inlet into which blood flow enters the prosthetic heart valve. As used herein, the term “outflow” generally refers to a position, direction, or portion of a prosthetic heart valve that is closer to an outlet from which blood flow exits the prosthetic heart valve.

[0040] Directions and other relative references (for example, inner, outer, upper, lower, etc.) may be used to facilitate discussion of the drawings and principles herein, but are not intended to be limiting. For example, certain terms may be used such as “inside,” “outside,”, “top,” “down,” “interior,” “exterior,” and the like. Such terms are used, where applicable, to provide some clarity of description when dealing with relative relationships, particularly with respect to the illustrated examples. Such terms are not, however, intended to imply absolute relationships, positions, and/or orientations. For example, with respect to an object, an “upper” part can become a “lower” part simply by turning the object over. Nevertheless, it is still the same part and the object remains the same. As used herein, “and/or” means “and” or “or,” as well as “and” and “or.”

Overview of an Exemplary Delivery Apparatus for Implanting a Prosthetic Valve [0041] A delivery apparatus for implanting a prosthetic, transcatheter heart valve via a patient’s vasculature can include an adjustment device for adjusting the position of a balloon relative to a crimped prosthetic valve (and/or vice versa). A balloon catheter can extend coaxially with a guide (or flex) catheter, and a balloon at a distal end of the balloon catheter can be positioned proximal or distal to a crimped prosthetic valve. As described below in more detail, the balloon and the crimped prosthetic valve can enter the vasculature of a patient through an introducer sheath and, once the balloon and the crimped prosthetic valve reach a suitable location in the body, the relative position of the prosthetic valve and balloon can be adjusted so that the balloon is positioned within a frame of the prosthetic valve so that the prosthetic valve eventually can be expanded at the treatment site. Once the crimped prosthetic valve is positioned on the balloon, the prosthetic valve is advanced to the vicinity of the deployment location (for example, the native aortic valve) and the adjustment device can further be used to accurately adjust or “fine tune” the position of the prosthetic valve relative to the desired deployment location.

[0042] FIG. 1 shows a delivery apparatus 10 adapted to deliver a prosthetic heart valve 12 (shown schematically in FIGS. 9-11) (for example, a prosthetic aortic valve) to a heart, according to one example. The apparatus 10 generally includes a steerable guide catheter 14 (FIG. 3), and a balloon catheter 16 extending through the guide catheter 14. The guide catheter can also be referred to as a flex catheter or a main catheter. The use of the term main catheter should be understood, however, to include flex or guide catheters, as well as other catheters that do not have the ability to flex or guide through a patient’ s vasculature.

[0043] The guide catheter 14 and the balloon catheter 16 in the illustrated example are adapted to slide longitudinally relative to each other to facilitate delivery and positioning of prosthetic valve 12 at an implantation site in a patient’s body, as described in detail below. In other examples, the balloon catheter 16 and the guide catheter 14 can be fixed relative to each other in proximal and distal directions and therefore may not slide longitudinally relative to each other.

[0044] The guide catheter 14 includes a handle portion 20 (or simply “handle”) and an elongated guide tube, or guide catheter shaft, 22 extending distally from the handle portion 20 (FIG. 3). FIG. 1 shows the delivery apparatus without the guide catheter shaft 22 for purposes of illustration. FIG. 3 shows the guide catheter shaft 22 extending from the handle portion 20 over the balloon catheter 16. The balloon catheter 16 includes a proximal portion 24 (such as in the form of a Y-connector, as shown) (FIG. I) adjacent to the handle portion 20 and an elongated shaft 26 (also referred to as “balloon catheter shaft’") that extends from the proximal portion 24 and through the handle portion 20 and a lumen 21 of the guide catheter shaft 22. The handle portion 20 can include a side arm 27 having an internal passage which fluidly communicates with a lumen defined by the handle portion 20.

[0045] As shown in FIG. 4, an inflatable balloon 28 can be mounted at a distal end of the balloon catheter 16. The delivery apparatus 10 can be configured to mount the prosthetic valve 12 in a crimped state that is initially offset from (for example, proximal to or distal to) the balloon 28 for insertion of the delivery apparatus and prosthetic valve into a patient’s vasculature, as described in detail in U.S. Publication No. 2009/0281619 (U.S. Application No. 12/247,846, filed October 8, 2008), which is incorporated herein by reference. Because the prosthetic valve 12 can be crimped at a location different from the location of the balloon 28 (for example, the prosthetic valve 12 is crimped proximal to the balloon 28 in the example depicted in FIG. 4), the prosthetic valve 12 can be crimped to a lower profile than would be possible if the prosthetic valve 12 was crimped on top of balloon 28. This lower profile permits a surgeon to navigate the delivery apparatus (including the crimped valve 12) more easily through a patient’ s vasculature to the treatment location. The lower profile of the crimped prosthetic valve is particularly helpful when navigating through portions of the patient’s vasculature which are particularly narrow, such as the iliac artery. The lower profile also allows for treatment of a wider population of patients, with enhanced safety.

[0046] As shown in FIG. 4, a nose cone 32 can be mounted at a distal end of the delivery apparatus 10 to facilitate advancement of the delivery apparatus 10 through the patient’s vasculature to the implantation site.

[0047] As can be seen in FIG. 5, the delivery apparatus 10 in the illustrated configuration further includes an inner shaft 34 (see also, FIG. 2A) that extends from the proximal portion 24 (also referred to as an “adaptor” or a “Y -connector”) and coaxially through a lumen 23 of the balloon catheter shaft 26 and the balloon 28. The balloon 28 can be mounted along a distal end portion 34d of the inner shaft 34. In one specific example, a proximal end 36 of the balloon 28 can be secured to a distal end 26d of balloon catheter shaft 26 (for example, with a suitable adhesive) (FIG. 5), and a distal end 37 of the balloon 28 can be secured to the nose cone 32 (for example, with a suitable adhesive) (FIG. 5). The outer diameter of inner shaft 34 can be sized such that an annular space is defined between the inner shaft 34 and the balloon catheter shaft 26 along an entire length of the balloon catheter shaft 26. The proximal portion 24 of the balloon catheter 16 can be formed with a fluid passageway (not shown) that is fluidly connectable to a fluid source (for example, a syringe containing an inflation fluid such as saline) for inflating the balloon 28. The fluid passageway is in fluid communication with the annular space between the inner shaft 34 and balloon catheter shaft 26 such that fluid from the fluid source can flow through the fluid passageway, through the annular space between the shafts 34 and 26, and into the balloon 28 to inflate the same and deploy the prosthetic valve 12.

[0048] The proximal portion 24 also defines an inner lumen that is in communication with a lumen 38 of the inner shaft 34 (FIG. 5). The lumen 38 is sized to receive a guide wire 18 (FIG. 1) that can extend coaxially through the inner shaft 34 and the nose cone 32. For example, the guide wire 18 can extend through the lumen 38 of the inner shaft 34 and a central lumen 33 of the nose cone 32. Thus, the inner shaft 34 can also be referred to as a “guide wire shaft,” and the lumen 38 can also be referred to as a “guide wire lumen.” [0049] The guide wire shaft 34 and balloon catheter shaft 26 can be formed from any of various suitable materials, such as nylon, braided stainless steel wires, or a polyether block amide (commercially available as Pebax®). The shafts 26, 34 can have longitudinal sections formed from different materials in order to vary the flexibility of the shafts along their lengths. The guide wire shaft 34 can have an inner liner or layer formed of Teflon® to minimize sliding friction with the guide wire 18.

[0050] In certain examples, the guide wire shaft 34 can comprise an inner tubular member and a braided layer surrounding the tubular member. Similarly, the balloon catheter shaft 26 can also have an inner tubular member and an outer braided layer surrounding the tubular member. In certain examples, the braided layers can be constructed from braided metal wires (for example, stainless steel wires, Nitinol wires, etc.). In certain examples, the braided layers can be formed from metal coils (for example, a stainless-steel coil, etc.). The braided layers can have various braid density along the shafts so as to impart desired flexibility and stiffness to different parts of the shafts. In certain examples, a metal braided layer can be replaced with a stainless steel hypotube that is formed with laser-cut and circumferentially extending openings. Additional examples of the braided layer are described in U.S. Patent No. 8,568,472, which is incorporated herein by reference in its entirety. [0051] The guide catheter shaft 22 comprises a steerable distal end portion 68 (also referred to as the “steerable section’") (FIG. 3), the curvature of which can be adjusted by an operator to assist in guiding the delivery apparatus 10 through the patient’s vasculature, and in particular, the aortic arch. The handle 20 in the illustrated embodiment comprises a distal handle portion 46 and a proximal handle portion 48. The distal handle portion 46 is configured to function as an actuation mechanism for adjusting the curvature of the steerable section 68 of the guide catheter shaft 22 and as a flex indicating device 51 that allows the operator to measure the relative amount of flex of the steerable section 68 of the guide catheter shaft 22. In addition, the flex indicating device 51 can provide a visual and tactile response at the handle 20, which provides the operator with an immediate and direct way to determine the amount of flex of the steerable section 68 of the guide catheter shaft 22.

[0052] The distal handle portion 46 can be operatively connected to the steerable section 68 and functions as an adjustment mechanism to permit the operator to adjust the curvature of the steerable section 68 via manual adjustment of the distal handle portion 46. Explaining further, the distal handle portion 46 comprises a flex activating member 50, the flex indicating device 51 (including an indicator pin 52), and a cylindrical main body, or housing 54. As shown in FIGS. 2 A and 2B, the flex activating member 50 comprises an adjustment knob 56 and a shaft 58 extending proximally from the knob into the housing 54. A proximal end portion of the guide catheter shaft 22 extends into and is fixed within a central lumen of the housing 54. An inner sleeve 70 surrounds a portion of the guide catheter shaft 22 inside the housing 54. A threaded slide nut 72 is disposed on and is slidable relative to the inner sleeve 70. The slide nut 72 is formed with external threads that mate with internal threads 60 of the shaft 58.

[0053] The slide nut 72 can have two slots formed on the inner surface of the nut and extending the length thereof. The sleeve 70 can be formed with longitudinally extending slots that are aligned with the slots of the slide nut 72 when the slide nut is placed on the sleeve 70. Disposed in each slot is a respective elongated nut guide 76, which can be in the form of an elongated rod or pin. The nut guides 76 extend radially into respective slots in the slide nut 72 to prevent rotation of the slide nut 72 relative to the sleeve 70. By virtue of this arrangement, rotation of the adjustment knob 56 (either clockwise or counterclockwise) causes the slide nut 72 to move longitudinally relative to the sleeve 70 in the directions indicated by the double-headed arrow 74. [0054] One or more pull wires 78 (FIG. 2A) couple the adjustment knob 56 to the steerable section 68 to adjust the curvature of the steerable section 68 upon rotation of the adjustment knob 56. For example, the proximal end portion of the pull wire 78 can extend into and can be secured to a retaining pin, such as by crimping the pin around the proximal end of the pull wire, which pin is disposed in a slot in the slide nut 72. The pull wire 78 extends from the pin, through the slot in the slide nut 72, a slot in the sleeve 70, and into and through a pull wire lumen in the guide catheter shaft 22. A distal end 78d of the pull wire 78 can be secured to a distal end 68d of the steerable section 68.

[0055] The pin, which retains a proximal end of the pull wire 78, is captured in the slot in the slide nut 72. Hence, when the adjustment knob 56 is rotated to move the slide nut 72 in the proximal direction, the pull wire 78 also is moved in the proximal direction. The pull wire 78 pulls the distal end 68d of the steerable section 68 back toward the distal handle portion 46, thereby bending the steerable section 68 and reducing its radius of curvature. The friction between the adjustment knob 56 and the slide nut 72 is configured to be sufficient to hold the pull wire 78 taut, thus preserving the shape of the bend in the steerable section 68 if the operator releases the adjustment knob 56. Thus, the friction between the adjustment knob 56 and the slide nut 72 can function as a locking mechanism for the pull wire 78. When the adjustment knob 56 is rotated in the opposite direction to move the slide nut 72 in the distal direction, tension in the pull wire 78 is released. The resiliency of the steerable section 68 causes the steerable section 68 to return its normal, non-deflected shape as tension on the pull wire 78 is decreased. Because the pull wire 78 is not fixedly secured to the slide nut 72 (for example, the pin can move within the slot in the nut), movement of the slide nut 72 in the distal direction does not push on the end of the pull wire 78, causing it to buckle. Instead, the pin is allowed to float within the slot of the slide nut 72 when the knob 56 is adjusted to reduce tension in the pull wire 78, preventing buckling of the pull wire 78.

[0056] In some examples, the steerable section 68 in its non-deflected shape is slightly curved and in its fully curved position, the steerable section 68 generally conforms to the shape of the aortic arch. In some examples, the steerable section 68 can be substantially straight in its non-deflected position.

[0057] The distal handle portion 46 can have other configurations that are adapted to adjust the curvature of the steerable section 68. One such alternative handle configuration is shown in U.S. Patent No. 7,780,723, which is incorporated herein by reference in its entirety. Additional details relating to the steerable section and handle configuration discussed above can be found in U.S. Patent No. 8,568.472, which is incorporated herein by reference in its entirety.

[0058] The shaft 58 also includes an externally threaded surface portion 62. As shown in FIG. 2B, a base portion 64 of the indicator pin 52 mates with the externally threaded surface portion 62 of the shaft 58. The shaft 58 extends into the housing 54 and the indicator pin 52 is trapped between the externally threaded surface portion 62 and the housing 54, with a portion of the indicator pin 52 extending into a longitudinal slot 66 of the handle. As the knob 56 is rotated to increase the curvature of the steerable section 68, the indicator pin 52 tracks the external threaded portion 62 of the flex activating member and moves in the proximal direction inside of the slot 66. The greater the amount of rotation of the knob 56, the further indicator pin 52 moves towards the proximal end of the proximal handle portion 46. Conversely, rotating the knob 56 in the opposite direction decreases the curvature of the steerable section 68 (that is, straightens the guide catheter shaft 22) and causes corresponding movement of the indicator pin 52 toward the distal end of the distal handle portion 46.

[0059] The flex indicating device 51 can include visual indicia on the outer surface of the housing 54 of the distal handle portion 46 can include visual indicia adjacent the slot 66 that indicate the amount of flex of the steerable section 68, based on the position of the indicator pin 52 relative to the visual indicia. Such indicia can identify the amount of flex in any of a variety of manners. For example, the outer surface of the housing 54 can include a series of numbers (for example, 0 to 10) adjacent the slot that indicate the amount of curvature of the steerable section 68 based on the position of the indicator pin 52 relative to the number scale. [0060] As described above, when the delivery apparatus 10 is introduced into the vasculature of the patient, a crimped prosthetic valve 12 can be positioned proximal to the balloon 28 (FIG. 4). Prior to expansion of the balloon 28 and deployment of prosthetic valve 12 at the treatment site, the prosthetic valve 12 can be moved relative to the balloon (or vice versa) to position the crimped prosthetic valve 12 on the balloon 28 for deploying (expanding) the prosthetic valve 12. As discussed below, the proximal handle portion 48 serves as an adjustment device that can be used to move the balloon 28 proximally into position within the frame of prosthetic valve 12, and further to accurately position the balloon 28 and the prosthetic valve 12 at the desired deployment location. [0061] As shown in FIGS. 2A and 2B, the proximal handle portion 48 comprises an outer housing 80 and an adjustment mechanism 82. The adjustment mechanism 82, which is configured to adjust the axial position of the balloon catheter shaft 26 relative to the guide catheter shaft 22, comprises an adjustment knob 84 and a shaft 86 extending distally into the housing 80. Mounted within the housing 80 on the balloon catheter shaft 26 is an inner support 88, which in turn mounts an inner shaft 90 (also referred to as a slider or sliding mechanism). The inner shaft 90 has a distal end portion 92 formed with external threads that mate with internal threads 94 that extend along the inner surface of the adjustment mechanism 82. The inner shaft 90 further includes a proximal end portion 96 that mounts a securement mechanism 98, which is configured to retain the position of the balloon catheter shaft 26 relative to the proximal handle portion 48 for use of the adjustment mechanism 82, as further described below. The inner shaft 90 can be coupled to the inner support 88 such that rotation of the shaft 86 causes the inner shaft 90 to move axially within the handle. For example, the inner support 88 can have an axially extending rod or rail that extends into slot formed in the inner surface of the inner shaft 90. The rod or rail prevents rotation of the inner shaft 90 but allows it to move axially upon rotation of the shaft 86.

[0062] The securement mechanism 98 includes internal threads that mate with external threads of the proximal end portion 96 of the inner shaft. Mounted within the proximal end portion 96 on the balloon catheter shaft 26 is a pusher element 100 and a shaft engagement member in the form of a collet 102. The collet 102 is configured to be manipulated by the securement mechanism 98 between a first state in which the collet 102 allows the balloon catheter shaft 26 to be moved freely in the longitudinal and rotational directions and a second state in which the collet 102 frictionally engages the balloon catheter shaft 26 and prevents rotational and longitudinal movement of the balloon catheter shaft 26 relative to the inner shaft 90, as further described below.

[0063] As best shown in FIGS. 6 and 7, the collet 102 comprises a distal end portion 104, an enlarged proximal end portion 106, and a lumen 108 that receives the balloon catheter shaft 26. A plurality of axially extending, circumferentially spaced slots 110 extend from the proximal end of the collet 102 to a location on the distal end portion 104, thereby forming a plurality of flexible fingers 1 12. The proximal end portion can be formed with a tapered end surface 114 that engages a corresponding tapered end surface of the pusher element 100 (FIG. 2A). [0064] As noted above, the securement mechanism 98 is operable to restrain movement of the balloon catheter shaft 26 (in the axial and rotational directions) relative to the proximal handle portion 48. Explaining further, the securement mechanism 98 is movable between a proximal position (shown in FIGS. 2A and 2B) and a distal position closer to the adjacent end of the knob 84. In the proximal position, the collet 102 applies little, if any, force against the balloon catheter shaft 26, which can slide freely relative to the collet 102, the entire handle 20, and the guide catheter shaft 22. When the securement mechanism 98 is rotated so as to move to its distal position closer to knob 84, the securement mechanism 98 urges the pusher element 100 against the proximal end of the collet 102. The tapered surface of the pusher element 100 pushes against the corresponding tapered surface 114 of the collet 102, forcing the fingers 112 radially inward against the outer surface of the balloon catheter shaft 26. The holding force of the collet 102 against the balloon catheter shaft 26 locks the balloon catheter shaft 26 relative to the inner shaft 90. In the locked position, rotation of the adjustment knob 84 causes the inner shaft 90 and the balloon catheter shaft 26 to move axially relative to the guide catheter shaft 22 (either in the proximal or distal direction, depending on the direction the knob 84 is rotated).

[0065] The adjustment knob 84 can be utilized to position the prosthetic valve 12 on the balloon 28 and/or once the prosthetic valve 12 is on the balloon, to position the prosthetic valve 12 and the balloon 28 at the desired deployment site within the native valve annulus. One specific method for implanting the prosthetic valve 12 in the native aortic valve is as follows. The prosthetic valve 12 initially can be crimped on a valve retaining region 120 (FIGS. 4 and 5) of the balloon catheter shaft 26 immediately adjacent the proximal end 36 of the balloon 28 or slightly overlapping the proximal end 36 of the balloon 28. The proximal end 12p of the prosthetic valve 12 can abut a distal end 122 of the guide catheter shaft 22 (FIG. 4), which keeps the prosthetic valve 12 in place on the balloon catheter shaft 26 as the delivery apparatus 10 and the prosthetic valve 12 are inserted through an introducer sheath. The proximal end of the valve retaining region 120 is distal to the distal end 78d of the pull wire 78. The prosthetic valve 12 can be delivered in a transfemoral procedure by first inserting an introducer sheath into the femoral artery and pushing the delivery apparatus 10 through the introducer sheath into the patient’s vasculature.

[0066] After the prosthetic valve 12 is advanced through the narrowest portions of the patient’s vasculature (for example, the iliac artery), the prosthetic valve 12 can be moved onto the balloon 28. For example, a convenient location for moving the prosthetic valve onto the balloon is the descending aorta. The prosthetic valve 12 can be moved onto the balloon 28, for example, by holding the handle portion 46 steady (which retains the guide catheter shaft 22 in place), and moving the balloon catheter shaft 26 in the proximal direction relative to the guide catheter shaft 22. As the balloon catheter shaft 26 is moved in the proximal direction, the distal end 122 of the guide catheter shaft 22 pushes against the prosthetic valve 12, allowing the balloon 28 to be moved proximally through the prosthetic valve 12 in order to center the prosthetic valve 12 on the balloon 28, as depicted in FIG. 9. The balloon catheter shaft 26 and/or the guide wire shaft 34 can include one or more radiopaque markers 25 to assist the operator in positioning the prosthetic valve 12 at the desired location on the balloon 28. The balloon catheter shaft 26 can be moved in the proximal direction by simply sliding/pulling the balloon catheter shaft 26 in the proximal direction if the securement mechanism 98 is not engaged to retain the balloon catheter shaft 26. For more precise control of the balloon catheter shaft 26, the securement mechanism 98 can be engaged to retain the balloon catheter shaft 26, in which case the adjustment knob 84 is rotated to effect movement of the balloon catheter shaft 26 and the balloon 28.

[0067] As shown in FIG. 5, the delivery apparatus 10 can further include a mounting member 124 secured to the outer surface of the guide wire shaft 34 within the balloon 28. The mounting member 124 helps retain the prosthetic valve 12 in place on the balloon 28 by facilitating the frictional engagement between the prosthetic valve 12 and the outer surface of the balloon 28. The mounting member 124 helps retain the prosthetic valve 12 in place for final positioning of the prosthetic valve 12 at the deployment location, especially when crossing the native leaflets, which typically are calcified and provide resistance against movement of the prosthetic valve 12.

[0068] The nose cone 32 has a tapered shape to facilitate atraumatic navigation through the patient’s vasculature. For example, the nose cone 32 can taper radially inwardly from a proximal end portion 32p of the nose cone 32 to a distal end 32d (also referred to as a “distal tip”) of the nose cone 32. In the example depicted in FIG. 5, the distal end 37 of the balloon 28 is affixed to the proximal end portion 32p of the nose cone 32.

[0069] The nose cone 32 can be connected to a shoulder portion 126 inside the balloon 28 to assist in positioning the prosthetic valve 12. The shoulder portion 126 desirably comprises a tapered member 125 that has a maximum diameter at its proximal end adjacent a distal end 12d of the prosthetic valve 12 (FIG. 9) and tapers in a distal direction toward the nose cone 32.

[0070] The shoulder portion 126 serves as a transition section between the nose cone 32 and the prosthetic valve 12 as the prosthetic valve 12 is pushed through the calcified native leaflets by shielding the distal end 12d of the prosthetic valve 12 from contacting the native leaflets. Although FIG. 9 shows the prosthetic valve 12 having a crimped diameter slightly larger than the diameter of the tapered member 125 at its proximal end, the tapered member 125 can have a diameter at its proximal end that is the same as or slightly larger than the diameter of the crimped prosthetic valve, or at least the same as or slightly larger than the diameter of the metal frame of the crimped prosthetic valve. In some examples, the nose cone 32 and the shoulder portion 126 can be constructed as a unitary piece, also referred to as a nose cone assembly.

[0071] As shown in FIG. 9, the prosthetic valve 12 can be positioned on the balloon for deployment such that the distal end 12d of the prosthetic valve 12 is slightly spaced from the tapered member 125. In some examples, prior to inflating the balloon, the guide catheter shaft 22 is moved proximally relative to the balloon catheter shaft 26 so that the guide catheter shaft 22 does not cover the inflatable portion of the balloon 28, and therefore the guide catheter shaft 22 does not interfere with inflation of the balloon 28. As will be covered below in greater detail, the need for this proximal motion of the guide catheter shaft 22 prior to balloon inflation is overcome in examples described below.

[0072] As the prosthetic valve 12 is guided through the aortic arch and into the ascending aorta, the curvature of the steerable section 68 can be adjusted (as explained in detail above) to help guide or steer the prosthetic valve 12 through that portion of the vasculature. As the prosthetic valve 12 is moved closer toward the deployment location within the aortic annulus, it becomes increasingly more difficult to control the precise location of the prosthetic valve 12 by pushing or pulling the handle portion 20 due to the curved section of the delivery apparatus. When pushing or pulling the handle portion 20, slack is removed from the curved section of the delivery apparatus before the pushing/pulling force is transferred to the distal end of the delivery apparatus. Consequently, the prosthetic valve may “jump” or move abruptly, making precise positioning of the prosthetic valve difficult.

[0073] In some examples, for more accurate positioning of the prosthetic valve 12 within the aortic annulus, the prosthetic valve 12 is placed as close as possible to its final deployment location (for example, within the aortic annulus such that an inflow end portion of the prosthetic valve 12 is in the left ventricle and an outflow end portion of the prosthetic valve 12 is in the aorta) by pushing/pulling the handle 20, and final positioning of the prosthetic valve 12 is accomplished using the adjustment knob 84. To use the adjustment knob 84, the securement mechanism 98 is placed in its locked position, as described above. Then, the handle 20 is held steady (which retains the guide catheter shaft 22 in place) while rotating the adjustment knob 84 to move the balloon catheter shaft 26, and thus the prosthetic valve 12, in the distal or proximal directions. For example, rotating the knob in a first direction (for example, clockwise), moves the prosthetic valve 12 proximally into the aorta, while rotating the knob in a second, opposite direction (for example, counterclockwise) advances the prosthetic valve 12 distally toward the left ventricle. Advantageously, operation of the adjustment knob 84 is effective to move the prosthetic valve 12 in a precise and controlled manner without sudden, abrupt movements as can happen when pushing or pulling the delivery apparatus 10 for final positioning.

[0074] When the prosthetic valve 12 is at the deployment location, the balloon 28 is inflated to expand the prosthetic valve 12 (as depicted in FIG. 11) so as to contact the native annulus. The expanded prosthetic valve becomes anchored within the native aortic annulus by the radial outward force of the valve’s frame against the surrounding tissue.

[0075] The mounting member 124 within the balloon is configured to allow the inflation fluid (for example, saline) to flow unobstructed from the proximal end 36 of the balloon 28 to the distal end 37 of the balloon 28. As best shown in FIG. 8, for example, the mounting member 124 comprises a coiled wire (for example, a metal coil) having a first section 124a, a second section 124b, a third section 124c, a fourth section 124d, and a fifth section 124e. When the prosthetic valve 12 is positioned on the balloon 28 for deployment, the second section 124b is immediately adjacent the proximal end of the prosthetic valve 12 and the fourth section 124d is immediately adjacent the distal end 12d of the prosthetic valve 12. The first and fifth sections 124a, 124e, respectively, which are at the proximal and distal ends of the mounting member 124, respectively, are secured to the balloon catheter shaft 26. The second, third, and fourth sections 124b, 124c, and 124d, respectively, are relatively larger in diameter than the first and fifth sections and are spaced radially from the outer surface of the balloon catheter shaft 26. As can be seen, the second section 124b and the fourth section 124d can be formed with spaces between adjacent coils. The third section can be formed with smaller spaces (or no spaces) between adjacent coils to maximize the surface area available to retain the prosthetic valve 12 on the balloon 28 during final positioning of the prosthetic valve 12 at the deployment location.

[0076] Referring to FIG. 10, the spacing between coils of the second and fourth sections 124b, 124d allows the inflation fluid to flow radially inwardly through the coils of the second section 124b, axially through the lumen of the third section 124c, radially outwardly through the coils of the fourth section 124d, into the distal section of the balloon, in the direction of arrows 128. The tapered member 125 also can be formed with one or more slots 130 that allow the inflation fluid to flow more easily past the tapered member 125 into the distal section of the balloon 28. In the illustrated embodiment, the tapered member 125 has three circumferentially spaced slots 130. Since the inflation fluid can pressurize and inflate the proximal and distal sections of the balloon at substantially the same rate, the balloon 28 can be inflated more evenly for controlled, even expansion of the prosthetic valve 12.

[0077] Additional features of the delivery apparatus and some variants of the delivery apparatus are described in U.S. Patent No. 9,339,384, which is incorporated by reference herein in its entirety.

[0078] As described above, to implant a prosthetic valve (for example, prosthetic valve 12) in a native heart valve of the patient, the delivery apparatus 10 can be introduced into a vasculature of the patient. The prosthetic valve 12 can be initially retained in a radially compressed configuration on a valve-retaining region 120 of the balloon catheter shaft 26. Once inside the patient’s vasculature, the position of the prosthetic valve 12 relative to the balloon 28 can be adjusted such that the prosthetic valve is centered on the balloon 28. When navigating the prosthetic valve 12 through an arched region of the vasculature (for example, the aortic arch), the curvature of the steerable section 68 can be adjusted, for example, by rotating the adjustment knob 56 to tension the pull wire 78. The prosthetic valve 12 can be positioned within or adjacent an annulus of the native heart valve. The prosthetic valve 12 can be positioned within the native annulus using the techniques previously described.

During the steps of positioning the prosthetic valve 12 on the balloon and positioning the prosthetic valve 12 at the target deployment site, the tip portion of the shaft 22 can abut the proximal end of the prosthetic valve 12 to either push the prosthetic valve 12 onto the balloon 28 and/or to prevent the prosthetic valve 12 from moving proximally relative to the balloon 28 during final positioning of the prosthetic valve 12. [0079] Prior to inflating the balloon 28, the guide catheter shaft 22 can be retracted proximally away from the balloon 28 for a sufficient distance so that the guide catheter does not interfere with balloon inflation. This can be accomplished, for example, by holding the proximal portion 24 stationary against the operating table and rotating the adjustment knob 84 in a direction that causes the handle 20 and the guide catheter shaft 22 to move proximally away from the balloon 28. Then, the prosthetic valve can be radially expanded and deployed by inflating the balloon 28.

[0080] Desirably, when deploying the prosthetic valve, the prosthetic valve is substantially coaxial with the annulus of the native heart valve so that the prosthetic valve can be evenly expanded and securely anchored within the annulus. In some circumstances, despite the initial position of the heart valve being coaxial with the native annulus, such coaxiality may be disturbed or lost after retracting the guide catheter shaft 22. As shown in FIG. 15, the prosthetic valve 12, mounted on the balloon 28, is aligned substantially coaxially within an aortic annulus 30. Retracting the guide catheter shaft 22 retracts the steerable section 68 farther away from the balloon 28 and the prosthetic valve 12. Without the structural support of the steerable section 68, the distal end portion 26d of the balloon catheter shaft 26 and the distal end portion 34d of the guide wire shaft 34 (where the balloon 28 and the prosthetic valve 12 are mounted) may deflect slightly relative to the steerable section 68. As a result, the prosthetic valve 12 may no longer be coaxial with the aortic annulus 30.

[0081] In some examples, after retracting the guide catheter shaft 22, an operator can still adjust the tension of the pull wire 78 to adjust the curvature of the steerable section 68 to help regain coaxiality, that is, to realign the central (longitudinal) axis of the prosthetic valve 12 with the central axis of the aortic annulus 30. However, such manipulation can be difficult. Because the distal end of the pull wire 78 ends at the steerable section 68 which is in a retracted position, the tensile force applied to the pull wire 78 may only be partially imparted to the distal end portion 26d of the balloon catheter shaft 26 to adjust the orientation of the prosthetic valve 12.

[0082] In some examples, the shaft 22 can be modified to permit full inflation of the balloon without the need to retract or otherwise move the shaft 22 relative to the balloon, thereby maintaining coaxiality of the prosthetic valve and the native aortic annulus.

[0083] To such ends, FIG. 12 shows a delivery apparatus 200, according to another example.

Common components of the delivery apparatus 200 and the delivery apparatus 10 are given the same reference numbers in FIGS. 12-15. In some examples, the delivery apparatus 200 is the same as the delivery apparatus 10 except for the differences described below. For example, the delivery apparatus 200 can include a balloon catheter shaft 26, an inner shaft 34, a flex activating member 50, a pull wire, etc., and these components are not repeated here for sake of brevity. However, it should be noted that the delivery apparatus 200 need not include all of the components described above for the delivery apparatus 10.

[0084] As shown, the distal end portion of the guide catheter shaft 22 includes a tip portion 202 comprising a plurality of flexible arms 204 (also referred to herein as flexible members). In some examples, there are at least three flexible arms 204, however, in other examples there may be more than three flexible arms 204 or only two flexible arms 204. The flexible arms 204 form the distal end portion of the guide catheter shaft 22 and extend over the proximal portion of the inflatable balloon 28. In some examples, the flexible arms 204 extend over at least 10% of a length of the balloon 28. In some examples, the flexible arms 204 extend over at least 15% or 25% of the length of the balloon. In some examples, the flexible arms 204 have a length of at least 5 mm; at least 6 mm in some examples; at least 7 mm in some examples, at least 8 mm in some examples, at least 9 mm in some examples, or at least 10 mm in some examples.

[0085] While the inflatable balloon 28 is in an uninflated state, the flexible arms 204 are in an unexpanded state and are parallel, or substantially parallel, with the longitudinal axis of the guide catheter shaft 22. In some examples, the distal ends of the flexible arms 204 abut the proximal end of the prosthetic valve 12. This contact between the ends of the flexible arms 204 and the prosthetic valve 12 may have the benefit of providing axial support to the prosthetic valve 12 and keeping it in place on the balloon 28. For example, the flexible arms 204 can resist proximal movement of the prosthetic valve 12 relative to the balloon as the delivery apparatus is advanced through an introducer sheath and/or the patient’s vasculature. In particular, the flexible arms 204 can be maintain the position of the prosthetic valve 12 on the balloon 28 while crossing the native aortic annulus 30 (as depicted in FIG. 15).

[0086] In some examples, if the prosthetic valve 12 is initially mounted offset from the central portion of the balloon (such as proximal to the balloon 28 as depicted in FIG. 4) for insertion into the patient’s vasculature, the prosthetic valve 12 can be repositioned to its deployment position on the balloon by moving the shaft 22 distally relative to the shaft 26 (or by moving the shaft 26 proximally relative to the shaft 22). During repositioning of the prosthetic valve, the arms 204 are sufficiently rigid to exert a distally-directed axial force on the prosthetic valve 12 to move the prosthetic valve relative to the balloon.

[0087] In some examples, the flexible arms 204 have a cross-sectional profile (the crosssection profile being in a plane perpendicular to the length of an arm) that is rectangular. In some examples the cross-sectional profile may be any of various shapes, including rounded rectangular, triangular, tapered, trapezoidal, pill shaped, or of another suitable shape.

[0088] The flexible arms 204 can made of any of various suitable biocompatible materials. In some examples, the flexible arms 204 can be made of any of various polymers, such as polyamide (nylon) or high density polyethylene (HDPE). In some examples, the flexible arms 204 can be made of a shape-memory and/or superelastic material, such as Nitinol. When made of a shape-memory material, such as Nitinol, the flexible arms 204 can have a non-deformed, shape memory state when in an unexpanded state (as shown in FIG. 12). After the fingers are radially expanded (as further described below), the fingers can revert back to the unexpanded state under their own resiliency.

[0089] In some examples, in the unexpanded state, each flexible arm 204 is in circumferential contact with its two adjacent flexible arms 204 along their respective lengths. In other words, each longitudinal side edge 210 of a flexible arm 204 is in contact with an adjacent side 210 of an adjacent arm 204 such that there are no gaps between adjacent arms 204 when the arms are in the unexpanded state. In some examples, the flexible arms 204 are spaced apart in a circumferential direction when the balloon 28 and the arms is in an unexpanded state; that is, the arms 204 define longitudinally extending gaps or slots between adjacent side edges 210 of adjacent arms 204.

[0090] As depicted in FIG. 13, inflating the inflatable balloon 28 causes the flexible arms 204 to passively expand radially outward to an expanded state with the expansion of the balloon 28 while the flexible arms 204 remain in contact with the outer surface of the balloon 28. As shown in FIG. 15, the prosthetic valve 12, mounted on the balloon 28, is aligned substantially coaxially within an aortic annulus 30. One benefit of the passive expansion of the flexible arms 204 is that the passive expansion allows for the balloon 28 to be inflated without the need for retracting the guide catheter shaft 22 off of the balloon 28.

Consequently, the guide catheter shaft 22 continues to provide radial support to the balloon 28 and prosthetic valve 12 while the balloon 28 is inflated. This radial support helps to preserve coaxiality with the native annulus during inflation and can avoid the need to re-align the prosthetic valve.

[0091] As illustrated in FIGS. 12-14, in some examples the flexible arms 204 may also be attached to a plurality of tension members 206 to produce active flexion of the flexible arms 204 relative to the balloon. In some examples, these tension members 206 comprise wires similar to the pull wire 78. The illustrated example shows one such tension member 206, which has a distal end 206d which terminates in a respective flexible arm 204 and a proximal end which is coupled to the handle portion 20. In some examples, each flexible arm 204 can have a respective tension member 206. In some examples, the distal end portion of each tension member 206 can extend through a lumen in the respective arm 204 and the distal end 206d is fixed relative to the arm 204.

[0092] In some examples, the handle portion 20 contains a control mechanism, which is configured to apply tension to the tension members 206. One or more tension members 206 couple the control mechanism on the handle 20 to the flexible arms 204 to adjust the curvature of the flexible arms 204. In some examples, the proximal end portions of the tension members 206 are operatively connected to the control mechanism, which can be operated by a user to apply tension to all of the tension members 206 concurrently. In some examples, the control mechanism can apply tension to at least one of the tension members 206 independent of tension applied to the other the tension members 206. In some examples, the control mechanism can apply tension to each tension member 206 independent of tension applied to the other tension members 206. In some examples the control mechanism comprises one or more control knobs, which are coupled to the proximal ends of one or more tension members 206.

[0093] In the example depicted in FIG. 12, the control mechanism comprises one control knob 208, which is operatively connected to the proximal end portions of the tension members 206 to apply tension to all tension members 206 upon rotation of the control knob 208. The control knob 208 and tension members 206 operate on similar principles as the adjustment knob 56 and pull wire 78 which controls steerable section 68 as is discussed in detail above. For example, the handle portion 20 can house a moveable nut (similar to nut 72) that is connected to the proximal end portions of the tension members 206, wherein the nut is configured to move axially within the handle portion upon rotation of the knob 208. Rotating the control knob 208 in a first direction (for example, clockwise), increases tension in the tension members 206 and causes the flexible arms 204 to flex outwardly. Rotating the control knob 208 in a second direction, opposite the first direction (for example, counterclockwise), decreases tension in the tension members 206 and allows the flexible arms 204 to revert back to their pre-deflected state.

[0094] When tension is applied to the tension members 206, the flexible arms 204 splay, or flex, radially outwardly from a longitudinal axis of the delivery apparatus 200. As shown in FIG. 14, this radially outward motion allows the flexible arms 204 to be partially or completely disengaged from the balloon 28 without retracting the guide catheter shaft 22 off of the balloon. This has the advantage of allowing the guide catheter shaft 22 to continue to provide radial support to the balloon 28 throughout the inflation of the balloon 28 while allowing for the flexible arms 204 to be removed from the balloon 28 prior to inflating the balloon.

[0095] In some examples, both passive and active expansion of the flexible arms 204 (via activation of the tension members 206) are used during deployment of the prosthetic valve. For example, once the prosthetic valve is positioned at the desired implantation location (for example, within the native aortic annulus), the flexible arms 204 can be passively expanded by inflating the balloon 28 to a partially inflated state corresponding to a partially expanded state of the arms 204 (FIG. 13). After the arms are partially expanded, tension in the tension members 206 can be increased to flex the arms 204 radially outwardly from the balloon corresponding to a further radially expanded state of the arms. Thereafter, the balloon can be further inflated to fully radially expand the prosthetic valve 12 (FIG. 14) into contact with the surrounding native annulus. After the prosthetic valve 12 is deployed, tension in the tension members 206 is decreased (for example, via rotation of the knob 208) to allow the arms 204 to revert back to the unexpanded state.

[0096] In some examples, only active expansion of the flexible arms 204 can be used. For example, once the prosthetic valve is positioned at the desired implantation location (for example, within the native aortic annulus), tension in the tension members 206 can be increased to flex the arms 204 radially outwardly from the uninflated balloon. Thereafter, the balloon 28 can be fully inflated to radially expanded the prosthetic valve 12 into contact with the surrounding native annulus.

[0097] In some examples, only passive expansion of the flexible arms 204 is used. In particular, once the prosthetic valve is positioned at the desired implantation location (for example, within the native aortic annulus), the balloon is fully inflated to radially expand the prosthetic valve 12 into contact with the surrounding native annulus, while the flexible arms 204 move to a fully expanded state while maintaining contact with the outer surface of the balloon. In such examples, the delivery apparatus 200 need not include the tension members 206, the control knob 208, and the associated components that transfer forces from the control knob 208 to the tension members 206.

[0098] It also should be noted that the delivery apparatus 200 can be used to deliver a prosthetic valve 12 that is initially mounted offset from the deployment location on the balloon (such as shown in FIG. 4) or a prosthetic valve 12 that is initially mounted on the deployment location on the balloon prior to insertion into the patient’s vasculature. As discussed above, when initially mounted offset from the deployment location on the balloon, the arms 204 can be used to apply a distally-directed force to the proximal end of the prosthetic valve in order to shift the prosthetic valve from its initial location to its deployment location on the balloon after the prosthetic valve is inserted into the patient’ s vasculature.

[0099] FIG. 16 shows a prosthetic heart valve 400, which can be one specific example of the prosthetic valve 12 described above. As shown, the heart valve 400 comprises a frame, or stent, 402 and a leaflet structure 404 supported by the frame. In some examples, the prosthetic heart valve 400 is adapted to be implanted in the native aortic valve and can be implanted in the body using, for example, the delivery apparatus 10 described above. The prosthetic valve 400 can also be implanted within the body using any of the other delivery apparatuses described herein.

[0100] In some examples, the frame 402 comprises a plastically expandable material, which can be metal alloys, polymers, or combinations thereof. Example metal alloys can comprise one or more of the following: nickel, cobalt, chromium, molybdenum, titanium, or other biocompatible metal. In some examples, the frame 402 can comprise stainless steel. In some examples, the frame 402 can comprise cobalt-chromium. In some examples, the frame 402 can comprise nickel-cobalt-chromium. In some examples, the frame 402 comprises a nickel- cobalt-chromium-molybdenum alloy, such as MP35N™ (tradename of SPS Technologies), which is equivalent to UNS R3OO35 (covered by ASTM F562-02). MP35N™/UNS R3OO35 comprises 35% nickel, 35% cobalt, 20% chromium, and 10% molybdenum, by weight.

[0101] In some examples, the prosthetic valve 12 or 400 can be a self-expandable prosthetic valve with a frame made from a self-expanding material, such as Nitinol. When the prosthetic valve is a self-expanding valve, the balloon of the delivery apparatus can be replaced with a sheath or similar restraining device that retains the prosthetic valve in a radially compressed state for delivery through the body. When the prosthetic valve is at the implantation location, the prosthetic valve can be released from the sheath, and therefore allowed to expand to its functional size. It should be noted that any of the delivery apparatuses disclosed herein can be adapted for use with a self-expanding valve.

Sterilization

[0102] Any of the systems, devices, apparatuses, etc. herein can be sterilized (for example, with heat/thermal, pressure, steam, radiation, and/or chemicals, etc.) to ensure they are safe for use with patients, and any of the methods herein can include sterilization of the associated system, device, apparatus, etc. as one of the steps of the method. Examples of heat/thermal sterilization include steam sterilization and autoclaving. Examples of radiation for use in sterilization include, without limitation, gamma radiation, ultra-violet radiation, and electron beam. Examples of chemicals for use in sterilization include, without limitation, ethylene oxide, hydrogen peroxide, peracetic acid, formaldehyde, and glutaraldehyde. Sterilization with hydrogen peroxide may be accomplished using hydrogen peroxide plasma, for example. Delivery Techniques

[0103] For implanting a prosthetic valve within the native aortic valve via a transfemoral delivery approach, the prosthetic valve is mounted in a radially compressed state along the distal end portion of a delivery apparatus. The prosthetic valve and the distal end portion of the delivery apparatus are inserted into a femoral artery and are advanced into and through the descending aorta, around the aortic arch, and through the ascending aorta. The prosthetic valve is positioned within the native aortic valve and radially expanded (e.g., by inflating a balloon, actuating one or more actuators of the delivery apparatus, or deploying the prosthetic valve from a sheath to allow the prosthetic valve to self-expand). Alternatively, a prosthetic valve can be implanted within the native aortic valve in a transapical procedure, whereby the prosthetic valve (on the distal end portion of the delivery apparatus) is introduced into the left ventricle through a surgical opening in the chest and the apex of the heart and the prosthetic valve is positioned within the native aortic valve. Alternatively, in a transaortic procedure, a prosthetic valve (on the distal end portion of the delivery apparatus) is introduced into the aorta through a surgical incision in the ascending aorta, such as through a partial J- stemotomy or right parasternal mini- thoracotomy, and then advanced through the ascending aorta toward the native aortic valve.

[0104] For implanting a prosthetic valve within the native mitral valve via a transseptal delivery approach, the prosthetic valve is mounted in a radially compressed state along the distal end portion of a delivery apparatus. The prosthetic valve and the distal end portion of the delivery apparatus are inserted into a femoral vein and are advanced into and through the inferior vena cava, into the right atrium, across the atrial septum (through a puncture made in the atrial septum), into the left atrium, and toward the native mitral valve. Alternatively, a prosthetic valve can be implanted within the native mitral valve in a transapical procedure, whereby the prosthetic valve (on the distal end portion of the delivery apparatus) is introduced into the left ventricle through a surgical opening in the chest and the apex of the heart and the prosthetic valve is positioned within the native mitral valve.

[0105] For implanting a prosthetic valve within the native tricuspid valve, the prosthetic valve is mounted in a radially compressed state along the distal end portion of a delivery apparatus. The prosthetic valve and the distal end portion of the delivery apparatus are inserted into a femoral vein and are advanced into and through the inferior vena cava, and into the right atrium, and the prosthetic valve is positioned within the native tricuspid valve. A similar approach can be used for implanting the prosthetic valve within the native pulmonary valve or the pulmonary artery, except that the prosthetic valve is advanced through the native tricuspid valve into the right ventricle and toward the pulmonary valve/pulmonary artery.

[0106] Another delivery approach is a transatrial approach whereby a prosthetic valve (on the distal end portion of the delivery apparatus) is inserted through an incision in the chest and an incision made through an atrial wall (of the right or left atrium) for accessing any of the native heart valves. Atrial delivery can also be made intravascularly, such as from a pulmonary vein. Still another delivery approach is a transventricular approach whereby a prosthetic valve (on the distal end portion of the delivery apparatus) is inserted through an incision in the chest and an incision made through the wall of the right ventricle (typically at or near the base of the heart) for implanting the prosthetic valve within the native tricuspid valve, the native pulmonary valve, or the pulmonary artery.

[0107] In all delivery approaches, the delivery apparatus can be advanced over a guidewire previously inserted into a patient’s vasculature. Moreover, the disclosed delivery approaches are not intended to be limited. Any of the prosthetic valves disclosed herein can be implanted using any of various delivery procedures and delivery devices known in the art.

[0108] The treatment techniques, methods, steps, etc. described or suggested herein or in references incorporated herein can be performed on a living animal or on a non-living simulation, such as on a cadaver, cadaver heart, anthropomorphic ghost, simulator (e.g., with the body parts, tissue, etc. being simulated), etc.

Additional Examples of the Disclosed Technology

[0109] In view of the above-described implementations of the disclosed subject matter, this application discloses the additional examples enumerated below. It should be noted that one feature of an example in isolation or more than one feature of the example taken in combination and, optionally, in combination with one or more features of one or more further examples are further examples also falling within the disclosure of this application.

[0110] Example 1. A delivery apparatus for delivering a medical implant to an implantation location within a patient’s body, the delivery apparatus comprising: a first shaft having a proximal end portion and a distal end portion; an inflatable balloon disposed on the distal end portion of the first shaft; a second shaft having a proximal end portion and a distal end portion, the second shaft extending co-axially over the first shaft; wherein the distal end portion of the second shaft comprises a tip portion comprising a plurality of longitudinally extending flexible arms extending over a proximal end portion of the balloon, wherein the arms are configured to flex radially outwardly from a longitudinal axis of the delivery apparatus upon inflation of the balloon.

[0111] Example 2. The delivery apparatus of any example herein, particularly example 1, wherein the plurality of flexible arms comprises three or more arms.

[0112] Example 3. The delivery apparatus of any example herein, particularly example 1, wherein the plurality of flexible arms comprises five or more arms.

[0113] Example 4. The delivery apparatus of any example herein, particularly any one of examples 1-3, wherein the flexible arms extend over at least 10% of a length of the balloon. [0114] Example 5. The delivery apparatus of any example herein, particularly any one of examples 1-3, wherein the flexible arms extend over at least 25% of a length of the balloon. [0115] Example 6. The delivery apparatus of any example herein, particularly any one of examples 1-5, further comprising a plurality of tension members, each tension member having a proximal end portion and a distal end portion, wherein the distal end portion of each tension member extends along a respective flexible arm.

[0116] Example 7. The delivery apparatus of any example herein, particularly example 6, wherein the tension members are configured to flex the arms radially outwardly from a longitudinal axis of the delivery apparatus when tension on the tension members is increased. [0117] Example 8. The delivery apparatus of any example herein, particularly example 7, wherein the tension members are configured to flex the arms radially away from an outer surface of the balloon when the tension on the tension members is increased.

[0118] Example 9. The delivery apparatus of any example herein, particularly any one of examples 7-8, wherein the tension applied to at least one of the tension members can be adjusted independent of the tension applied to the other tension members.

[0119] Example 10. The delivery apparatus of any example herein, particularly any one of examples 7-8, wherein the tension applied to each tension member can be adjusted independent of each other.

[0120] Example 11. The delivery apparatus of any example herein, particularly any one of examples 7-8, further comprising a handle coupled to the proximal end portion of the second shaft and the proximal end portions of the tension members, wherein the handle comprises a control mechanism configured to adjust the tension in the tension members.

[0121] Example 12. The delivery apparatus of any example herein, particularly example 11, wherein the control mechanism is a knob configured to apply tension to the tension members when the knob is rotated.

[0122] Example 13. The delivery apparatus of any example herein, particularly any one of examples 1-12, wherein the flexible arms have a length of least 8 mm.

[0123] Example 14. The delivery apparatus of any example herein, particularly any one of examples 1-13, wherein when the balloon is in a non-inflated state, the flexible arms are in an unexpanded state in which each flexible arm is in contact with two adjacent flexible arms.

[0124] Example 15. The delivery apparatus of any example herein, particularly any one of examples 1-14, wherein when the balloon is on a non-inflated state, the flexible arms are in an unexpanded state in which the flexible arms are spaced apart from each other in a circumferential direction.

[0125] Example 16. The delivery apparatus of any example herein, particularly any one of examples 6-15, wherein the tension members comprise wires. [0126] Example 17. The delivery apparatus of any example herein, particularly any one of examples 1-16, in combination with an expandable medical implant in a radially compressed state disposed around the inflatable balloon.

[0127] Example 18. The delivery apparatus and the expandable medical implant of any example herein, particularly example 17, wherein the expandable medical implant is a prosthetic heart valve comprising an expandable stent and a leaflet structure supported by the stent.

[0128] Example 19. The delivery apparatus and the expandable medical implant of any example herein, particularly any one of examples 17-18, wherein distal ends of the flexible arms contact a proximal end of the expandable medical implant.

[0129] Example 20. The delivery apparatus and the expandable medical implant of any example herein, particularly example 19, wherein the distal ends of the flexible arms apply an axial force to the proximal end of the medical implant.

[0130] Example 21. A delivery system for delivering a medical implant to an implant location comprising: a first, balloon catheter having a proximal end portion and a distal end portion; an expandable balloon disposed on the distal end portion of the balloon catheter; an expandable medical implant disposed around the balloon catheter in a radially compressed state; a second catheter having a proximal end portion and a distal end portion, the second catheter extending over at least a portion of the balloon catheter and sharing a common axis with the balloon catheter; wherein the distal end portion of the second catheter comprises a plurality of longitudinally extending flexible members which extend over a proximal end portion of the balloon, wherein the flexible members are configured to bend radially outwardly from a longitudinal axis of the delivery system upon expansion of the balloon. [0131] Example 22. The delivery system of any example herein, particularly example 21, wherein the plurality of flexible members comprises two or more members.

[0132] Example 23. The delivery system of any example herein, particularly example 21, wherein the plurality of flexible members comprises six or more members.

[0133] Example 24. The delivery system of any example herein, particularly any one of examples 21-23, wherein the expandable implant is disposed around the expandable balloon. [0134] Example 25. The delivery system of any example herein, particularly any one of examples 21-23, wherein the expandable implant is disposed around the balloon catheter proximal to the balloon. [0135] Example 26. The delivery system of any example herein, particularly any one of examples 21-25, wherein each flexible member contains a distal end portion of a tension member, wherein the tension member is configured to flex the flexible member radially outwardly from a longitudinal axis of the delivery system upon application of tension to the tension member.

[0136] Example 27. The delivery system of any example herein, particularly example 26, further comprising a control mechanism operatively coupled to a proximal end portion of each tension member, wherein the control mechanism is configured to adjust tension in the tension members.

[0137] Example 28. The delivery system of any example herein, particularly example 27, wherein the control mechanism is a knob.

[0138] Example 29. The delivery system of any example herein, particularly any one of examples 21-28, wherein distal ends of the flexible members abut a proximal end of the implant.

[0139] Example 30. The delivery system any example herein, particularly example 29, wherein the flexible members apply a distally-directed axial force on the proximal end of the implant.

[0140] Example 31. The delivery system of any example herein, particularly any one of examples 21-30, wherein the implant comprises a prosthetic heart valve.

[0141] Example 32. The delivery system of any example herein, particularly example 31, wherein the prosthetic heart valve comprises an annular frame and a plurality of leaflets disposed in the frame.

[0142] Example 33. The delivery system of any example herein, particularly any one of examples 21-32, wherein the flexible members have a length of at least 8 mm.

[0143] Example 34. The delivery system of any example herein, particularly any one of examples 21-33, wherein when the balloon is in a non-inflated state, the flexibles members are in an unexpanded state in which opposing longitudinal side edges of each flexible member contact adjacent longitudinal side edges of adjacent flexible members.

[0144] Example 35. The delivery system of any example herein, particularly any one of examples 21 -33, wherein when the balloon is in a non-inflated state, the flexibles members are in an unexpanded state in which adjacent flexible members are separated by longitudinally extending slots. [0145] Example 36. The delivery system of any example herein, particularly any one of examples 21-35, wherein the flexible members extend over at least 15% of a length of the balloon.

[0146] Example 37. The delivery system of any example herein, particularly any one of examples 21-35, wherein the flexible members extend over at least 25% of a length of the balloon.

[0147] Example 38. A method of implanting a medical implant, the method comprising: introducing a delivery device into the body of a patient, the delivery device comprising a handle portion, an elongated first shaft and an elongated second shaft extending from the handle portion, wherein the second shaft extends co-axially over the first shaft, the first shaft having a distal end portion mounting an inflatable balloon and a medical implant in a radially compressed state, the second shaft having a distal end portion comprising a plurality of longitudinally extending flexible arms; advancing the distal end portion of the delivery device towards an implant location until the medical implant is within or adjacent to a desired implantation position; and inflating the balloon to cause the medical implant to radially expand and cause the plurality of longitudinally extending flexible arms to passively expand with the expansion of the balloon.

[0148] Example 39. The method of any example herein, particularly example 38, wherein the delivery device further comprises a plurality of tension members each tension member having a proximal end portion and a distal end portion and wherein the distal end portion of each tension member extends along a respective flexible arm, after the passive expansion of the longitudinally extending flexible arms, tensioning the tension members, which causes the flexible arms to bend outward away from the balloon.

[0149] Example 40. The method of any example herein, particularly example 39, wherein the proximal end of each tension member is operatively coupled to a knob on the handle, wherein tensioning the tension members comprises rotating the knob until the flexible arms are at least partially disengaged from the balloon.

[0150] Example 41. The methods of any example herein, particularly any one of examples 38-40, wherein the medical implant is a prosthetic heart valve, the act of advancing comprises advancing the distal end portion of the delivery device through the aorta until the medical implant is within or adjacent to a native aortic valve. [0151] Example 42. The delivery apparatus or system of any example herein, particularly any one of examples 1-37, wherein the delivery apparatus or system is sterilized.

[0152] The features described herein with regard to any example can be combined with other features described in any one or more of the other examples, unless otherwise stated. For example, any one or more features of one delivery apparatus can be combined with any one or more features of another delivery apparatus.

[0153] In view of the many possible ways in which the principles of the disclosure may be applied, it should be recognized that the illustrated configurations depict examples of the disclosed technology and should not be taken as limiting the scope of the disclosure nor the claims. Rather, the scope of the claimed subject matter is defined by the following claims and their equivalents.

Claims

We claim:

1. A delivery apparatus for delivering a medical implant to an implantation location within a patient’s body, the delivery apparatus comprising: a first shaft having a proximal end portion and a distal end portion; an inflatable balloon disposed on the distal end portion of the first shaft; and a second shaft having a proximal end portion and a distal end portion, the second shaft extending co-axially over the first shaft, wherein the distal end portion of the second shaft comprises a tip portion comprising a plurality of longitudinally extending flexible arms extending over a proximal end portion of the balloon, wherein the arms are configured to flex radially outwardly from a longitudinal axis of the delivery apparatus upon inflation of the balloon.

2. The delivery apparatus of claim 1, wherein the plurality of flexible arms comprises three or more arms.

3. The delivery apparatus of any one of claims 1-2, wherein the flexible arms extend over at least 10% of a length of the balloon.

4. The delivery apparatus of any one of claims 1-2, wherein the flexible arms extend over at least 25% of a length of the balloon.

5. The delivery apparatus of any one of claims 1-4, further comprising a plurality of tension members, each tension member having a proximal end portion and a distal end portion, wherein the distal end portion of each tension member extends along a respective flexible arm.

6. The delivery apparatus of claim 5, wherein the tension members are configured to flex the arms radially outwardly from a longitudinal axis of the delivery apparatus when tension on the tension members is increased.

7. The delivery apparatus of claim 6, wherein the tension applied to at least one of the tension members can be adjusted independent of the tension applied to the other tension members.

8. The delivery apparatus of claim 6, wherein the tension applied to each tension member can be adjusted independent of each other.

9. The delivery apparatus of any one of claims 5-8, further comprising a handle coupled to the proximal end portion of the second shaft and the proximal end portions of the tension members, wherein the handle comprises a control mechanism configured to adjust the tension in the tension members.

10. The delivery apparatus of any one of claims 1-9, wherein the flexible arms have a length of least 8 mm.

11. A delivery system for delivering a medical implant to an implant location comprising: a first, balloon catheter having a proximal end portion and a distal end portion; an expandable balloon disposed on the distal end portion of the balloon catheter; an expandable medical implant disposed around the balloon catheter in a radially compressed state; and a second catheter having a proximal end portion and a distal end portion, the second catheter extending over at least a portion of the balloon catheter and sharing a common axis with the balloon catheter, wherein the distal end portion of the second catheter comprises a plurality of longitudinally extending flexible members which extend over a proximal end portion of the balloon, wherein the flexible members are configured to bend radially outwardly from a longitudinal axis of the delivery system upon expansion of the balloon.

12. The delivery system of claim 1 1 , wherein the plurality of flexible members comprises two or more members.

13. The delivery system of any one of claims 11-12, wherein each flexible member contains a distal end portion of a tension member, wherein a proximal end portion of the tension member is disposed within a handle portion coupled to the proximal end portion of the second shaft, and wherein the tension member is configured to flex the flexible member radially outwardly from a longitudinal axis of the delivery system upon application of tension to the tension member.

14. The delivery system of claim 13, further comprising a control mechanism disposed on the handle portion and operatively coupled to a proximal end portion of each tension member, wherein the control mechanism is configured to adjust tension in the tension members.

15. The delivery system of any one of claims 11-14, wherein distal ends of the flexible members abut a proximal end of the implant.

16. The delivery system of any one of claims 11-15, wherein the flexible members apply a distally-directed axial force on the proximal end of the implant.

17. The delivery system of any one of claims 11-16, wherein the implant comprises a prosthetic heart valve.

18. The delivery system of any one of claims 11-17, wherein the flexible members extend over at least 15% of a length of the balloon.

19. A method of implanting a medical implant, the method comprising: introducing a delivery device into the body of a patient, the delivery device comprising a handle portion, an elongated first shaft and an elongated second shaft extending from the handle portion, wherein the second shaft extends co-axially over the first shaft, the first shaft having a distal end portion mounting an inflatable balloon and a medical implant in a radially compressed state, the second shaft having a distal end portion comprising a plurality of longitudinally extending flexible arms; advancing the distal end portion of the delivery device towards an implant location until the medical implant is within or adjacent to a desired implantation position; and inflating the balloon to cause the medical implant to radially expand and cause the plurality of longitudinally extending flexible arms to passively expand with the expansion of the balloon.

20. The method of claim 19, wherein the delivery device further comprises a plurality of tension members each tension member having a proximal end portion and a distal end portion and wherein the distal end portion of each tension member extends along a respective flexible arm, after the passive expansion of the longitudinally extending flexible arms, tensioning the tension members, which causes the flexible arms to bend outward away from the balloon.