Delivery apparatus for prosthetic implants

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 second shaft extending through a lumen of the first shaft, and a balloon mounted along the distal end portion of the second shaft. A distal end of the first shaft having one or more biasing elements wherein the one or more biasing elements are configured to provide bias to prevent the formation of a gap between the distal end of the first shaft and the proximal end of a medical implant.

Description

DELIVERY APPARATUS FOR PROSTHETIC IMPLANTSCROSS REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 553,088, filed February 13, 2024, which is incorporated by reference herein.FIELD

[0002] The present disclosure concerns delivery apparatuses, systems, and methods for implantation of a prosthetic implants such as stents and / or prosthetic heart valves.BACKGROUNDThe 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

[0003] Described herein are apparatus and methods for delivering prosthetic implants, such as prosthetic heart valves and / or stents, through the body and into an implant site, such as the heart, for implantation therein. The prosthetic implants (also referred to herein as “prostheticdevices”) delivered with the delivery apparatus (also referred to herein as “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 apparatus. Exemplary delivery routes through the body and into the heart include transfemoral routes, transseptal 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, a prosthetic mitral valve, a prosthetic pulmonary valve, and / or a prosthetic tricuspid 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.

[0004] In one of its basic configurations, a delivery apparatus for a prosthetic implant can comprise a handle and one or more shafts coupled to the handle. This basic configuration can preferably be provided with any one or more of the features described elsewhere herein, in particular with those of the examples described hereafter. However, it should be understood that the basic configuration can preferably also be provided with any one or more of the features shown in the figures and / or described in conjunction with the figures, either in addition to or alternatively to the features of the examples described hereafter.

[0005] In some examples, a delivery apparatus can comprise a first shaft extending distally from the handle and a second shaft extending through a lumen of the first shaft.

[0006] In some examples, the delivery apparatus can further include a pull wire extending longitudinally along the first shaft. A distal end of the pull wire is fixed relative to the distal end of the first shaft. Tension in the pull wire can be adjusted to adjust a curvature of the distal end portion of the first shaft.

[0007] In some examples the delivery apparatus can comprise: a first shaft having a first section and a second section, and a lumen extending through the first section and the second section; a second shaft having a proximal end portion and a distal end portion, the second shaft extending through the lumen of the first shaft; and one or more biasing elements coupled to and disposed between the first section and the second section of the first shaft, wherein the one or morebiasing elements are configured to bias the first section of the first shaft away from the second section of the first shaft and toward the distal end portion of the second shaft. In some examples the one or more biasing elements includes a coil compression spring.

[0008] In some examples, the delivery apparatus is a part of an assembly further comprising an expandable medical implant in a radially compressed state, wherein the expandable medical implant is disposed around the expansion device.

[0009] In some examples, the one or more biasing elements is in a compressed state between the distal end of the first shaft and a proximal end of the expandable medical implant such that the first section of the first shaft applies a distally-directed force to the proximal end of the expandable implant.

[0010] In some examples, the one or more biasing elements is configured to move from a compressed state to an expanded state to maintain the first section of the first shaft against the proximal end of the expandable medical implant as the expandable medical implant is advanced to the implantation location. In some examples, the one or more biasing elements moves between the compressed state and the expanded state as the curvature of the first shaft changes.

[0011] In some examples the medical implant comprises a prosthetic heart valve, a stent, or a support structure for a prosthetic heart valve.

[0012] In other examples the distal end of the first shaft can further include a biasing element which abuts the proximal end portion of the medical implant and applies an axial forward force on the proximal end of a prosthetic implant mounted on the balloon.

[0013] In some examples the delivery device is used as a part of a method that comprises introducing a delivery apparatus into a patient’s body; and adjusting tension in a pull wire of the delivery apparatus to steer the delivery apparatus through the patient’ s vasculature, wherein adjusting the tension in the pull wire results in one or more biasing members of the delivery apparatus expanding from a compressed state to an expanded state to maintain a distal end of a first shaft in contact with a proximal end of the medical implant.

[0014] 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).

[0015] The various innovations of this disclosure can be used in combination or separately. This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. The foregoing and other objects, features, and advantages of the disclosure will become more apparent from the following detailed description, claims, and accompanying figures.BRIEF DESCRIPTION OF THE DRAWINGS

[0016] FIG. 1 is a side view of a delivery apparatus for implanting a prosthetic heart valve, according to one example.

[0017] FIG. 2 is side view of a section of the handle and a section of the distal end portion of the delivery apparatus of FIG. 1.

[0018] FIG. 3 is a side view of the delivery apparatus of FIG. 1 with an uninflated balloon and the spring in an uncompressed state.

[0019] FIG. 4 is a side view of the delivery apparatus of FIG. 1 with an uninflated balloon and the spring in a compressed state.

[0020] FIG. 5 depicts the delivery apparatus of FIG. 1 with the spring in a partially relaxed state to cover the gap between the end portion of the steerable section and the proximal portion of the implant as a prosthetic valve mounted on a balloon is positioned within an aortic annulus, according to one example.

[0021] FIGS. 6-7 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.

[0022] FIG. 8 depicts a side view of a delivery apparatus with an uninflated balloon and the spring in a compressed state, according to another example.

[0023] FIG. 9 depicts an example of a prosthetic heart valve that can be implanted using any of the delivery apparatuses disclosed herein.DETAILED DESCRIPTIONGeneral Considerations

[0024] It should be understood that the disclosed examples can be adapted to deliver and implant prosthetic devices 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.).

[0025] 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.

[0026] 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.

[0027] 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.

[0028] 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.

[0029] As described herein, the term “inflow” can generally refer 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 described herein, the term “outflow” can generally refer 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.

[0030] 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

[0031] In some instances, 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). In some examples, a balloon catheter can extend coaxially through 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 prosthetic valve eventually can be expanded at the treatment site. The prosthetic valve is advanced to the vicinity of the deployment location (for example, the native aortic valve), and (in particular implementations) 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. Additional information about the adjustment mechanism and / or implantation procedure can be found, for example, in U.S. Patent No. 9,339,384 and U.S. Publication No. 2023 / 0210657, which are incorporated by reference herein.

[0032] FIG. 1 shows a delivery apparatus 10 adapted to deliver a prosthetic valve 12 (shown schematically in FIGS. 6-7) (for example, a prosthetic aortic valve) to a heart, according to one example. The apparatus 10 generally includes a steerable guide catheter 14, and a balloon catheter 16 extending through the guide catheter 14. The guide catheter can also be referred to as “a flex catheter,” “a main catheter,” or “an outer 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. The use of the term “outer catheter” not necessarily mean “outermost” nor does it preclude one or more additional catheters or shafts being outside of the outer catheter; rather, it means that the catheter is radially outward relative to at least one catheter (e.g., the balloon catheter) or shaft.

[0033] 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.

[0034] 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. 1 shows the guide catheter shaft 22 extending from the handle portion 20 over theballoon catheter 16. The balloon catheter 16 includes a proximal portion 24 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 of the guide catheter shaft 22. In some instances, the handle portion 20 can include a flush port 27 having an internal passage which fluidly communicates with a lumen defined by the handle portion 20.

[0035] An inflatable balloon 28 can be mounted at a distal end of the balloon catheter 16 to facilitate expansion of a prosthetic implant within a patient’s body. A nose cone 32 can be mounted at a distal end of the delivery apparatus 10 to facilitate atraumatic advancement of the delivery apparatus 10 through the patient’s vasculature to the implantation site.

[0036] In some examples, the balloon catheter can comprise a lumen extending therethrough. In some instances, the lumen can be configured, for example, to receive a guidewire.

[0037] The 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 shaft 26 can have longitudinal sections formed from different materials in order to vary the flexibility of the shaft along its length.

[0038] In certain examples, the balloon catheter shaft 26 can comprise an inner tubular member and an outer braided layer surrounding the tubular member. In certain examples, the braided layer can be constructed from braided metal wires (for example, stainless steel wires, Nitinol wires, etc.). In certain examples, the braided layer can be formed from metal coils (for example, a stainless-steel coil, etc.). The braided layer 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 by reference herein in its entirety.

[0039] The guide catheter shaft 22 comprises a steerable distal end portion 68 (also referred to as the “steerable section”) (FIG. 2), the curvature of which can be adjusted by an operatorto assist in guiding the delivery apparatus 10 through the patient’s vasculature, and in particular, the aortic arch. The handle 20 in the illustrated example 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. 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 a flex activating member 50 on the distal handle portion 46. 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.

[0040] 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.

[0041] 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 by reference herein 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 by reference herein in its entirety.

[0042] The flex indicating device 51 can include visual indicia on the outer surface of the main body 54 of the distal handle portion 46 such as visual indicia that indicate the amount of flex of the steerable section 68, based on the position of an 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 main body 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.

[0043] In some examples, a 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 aproximal position and a distal position closer to the adjacent end of the knob 84. In the proximal position, the securement mechanism applies little, if any, force against the balloon catheter shaft 26, which can slide freely relative to 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 locks the balloon catheter shaft 26 relative to distal handle portion 46. In the locked position, rotation of the adjustment knob 84 causes 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).

[0044] 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.

[0045] 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. 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 prostheticvalve 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.

[0046] Additional features of the delivery apparatus and some variants of the delivery apparatus are described in U.S. Patent No. 9,339,384 and U.S. Publication No. 2023 / 0210657.

[0047] 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. 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 to help guide or steer the prosthetic valve 12 through that portion of the vasculature. Referring to FIG. 3, the steerable section 68 of the guide catheter shaft 22 comprises a pull wire 78 which has its distal end 78d at the distal end 68d of the steerable section 68. 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.

[0048] Flexing the steerable section 68 of the guide catheter shaft 22 to adjust the curvature can, in some instances, result in the guide catheter shaft foreshortening relative to the balloon catheter shaft 26. The shaft 22 comprises features to compensate for the foreshortening. These features can, for example, prevent or reduce the likelihood of a gap forming between the distal end of the guide catheter shaft 22 and the proximal end of the prosthetic valve 12. Maintaining the distal end of the guide catheter 22 against the proximal end of the prosthetic valve can provide one or more advantages. For example, it can prevent the valve from moving proximally relative to the balloon. Additionally (or alternatively), it can provide a relatively smooth transition from the prosthetic valve to the guide catheter shaft, which enables it to pass with less friction through the patient’s vasculature.

[0049] As shown in FIG. 1 , the distal end portion of the guide catheter shaft 22 may comprise one or more biasing elements (also called biasing members). As shown in FIG 3, in some examples the one or more biasing elements may be deposited between two segments of the guide catheter shaft 22. There may be a first segment 42 of shaft 22 coupled to the distal end of the one or more biasing elements and a second segment 44 of shaft 22 coupled to the proximal end of the biasing element and extending to the handle portion 20. In some examples, the proximal end of the biasing element is coupled to the distal end 68d of thesteerable section 68. Both the first segment 42 and the second segment 44 are part of the guide catheter shaft 22 and may be of the same shape and material. The first segment 42 of the shaft 22 is deposited between the biasing element and the prosthetic valve 12 and may serve to create a better fit between the distal end of the spring 40 and the proximal end of the prosthetic valve 12.

[0050] In the illustrated example, the one or more biasing elements is a coil compression spring 40. The spring 40 is disposed between the distal end 68d of the steerable section 68 and the proximal end of the first segment 42 of the guide catheter shaft 22 and is coaxial with the guide catheter shaft 22. In some examples, this spring 40 can comprise stainless steel, Nitinol, and / or other materials with similar elastic properties. In some examples, a plurality of compression springs can be used. The various springs can comprise the same or different spring rates. In some examples, the one or more biasing element can comprise a volute spring or another type of elastic device that is biased to an axially expanded configuration and that can be moved to an axially compressed state. In some examples, one or more compression springs and / or one or more other biasing members can be used (e.g., one or more compression springs and / or one or more volute springs).

[0051] In some instances, as depicted in FIGS. 1-7, the biasing element, such as the spring 40, is exposed and un-encased. This may have the advantage of simplifying the preparation of the apparatus by allowing the operator to observe the spring compression as tension is applied during preparation of the device, which is discussed in detail below.

[0052] In other instances, as depicted in FIG. 8, the biasing element, such as the spring 40, may be overmolded, surrounded by a jacket / sleeve 222, or otherwise encased in material in a way that does not significantly restrain the expansion or contraction of the biasing element. This may be accomplished by using material which is softer, and / or more elastic, than the material of the guide catheter shaft 22. In some examples, the guide catheter shaft 22 has a first durometer hardness and the sleeve has a second durometer hardness, wherein the first durometer hardness is greater than the second durometer hardness. This sleeve 222 may have the advantage of reducing friction between the biasing element the vasculature of the patient. The overmolding, as depicted in FIG. 8, may likewise be applied to any example herein, including the examples depicted in FIGS. 1-7.

[0053] FIG. 3 depicts the delivery apparatus with the spring 40 in an uncompressed state andFIG. 4 depicts the delivery apparatus with the spring 40 in a compressed state. The spring 40is compressed by applying a proximally directed axial force to the balloon catheter 26. This force causes the balloon catheter 26 (and by extension the balloon 28 and prosthetic valve 12) to move in the proximal direction relative to the guide catheter shaft 22 causing the spring 40 to move from an uncompressed state to a compressed state. The spring 40 (and / or any other biasing element) may be compressed and / or expanded before the delivery apparatus is inserted into a patient. Additionally (or alternatively) the biasing element may be compressed and / or expanded while the delivery apparatus is disposed within a patient’s vasculature.

[0054] As one example, the spring 40 may be compressed during the preparation of the device prior to introduction of the delivery apparatus 10 into the vasculature of the patient. Prior to introduction of the delivery apparatus 10, a crimped prosthetic valve 12 can be moved relative to the balloon (or vice versa) to position the crimped prosthetic valve 12 on the balloon 28. Then the balloon catheter shaft and the guide catheter shaft can be moved relative to one another to cause the spring 40 to be compressed between the distal end of the second segment 44 and the proximal end of first segment 42 of shaft 22. As discussed above, 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.

[0055] In some examples, the delivery apparatus can include one or more markers on the proximal portion of the balloon catheter 26 adjacent to the handle 20 which can assist the operator by indicating the amount of tension which has been applied to the balloon catheter shaft 26. These markers assist the operator to determine the proper tension to be applied, such as during the preparation of the device on the back table prior to insertion. The markers can provide one or more advantages. For example, one advantage of the markers is that, due to the long working lengths of the delivery device catheters, an operator can quickly and easily determine when the spring 40 is properly compressed by viewing the marker adjacent the handle without the need to visually check the spring 40 at the distal end portion of the delivery apparatus. Another example advantage of the markers is that the operator can manipulate the compression of the spring 40 and have a visual indication of the state of the spring when the end of the delivery device is not visible (or may be less visible), such as when the device is inserted into the body and / or under fluoroscopy.

[0056] In the in the example depicted in FIG. 4, the delivery apparatus comprises a single marker 58 disposed on the balloon catheter shaft 26 to indicate the proper tension. As the delivery apparatus is manipulated from the uncompressed state depicted in FIG. 3 to thecompressed state depicted in FIG. 4 the balloon catheter shaft 26 moves axially proximally relative to the guide catheter 22 and the handle 20. This relative motion results in the marker 58, which in FIG. 3 was obscured by the handle, becoming visible in FIG. 4. This single marker provides an indica of when the spring is compressed to a desired state. This can, for example, prevent over compression of the biasing element. This can also prevent too much axially forward force from being applied to the valve 12 which can cause the valve 12 to move relative to the balloon.

[0057] In other examples the one or more marks may be a series of marks, such as lines, numbers, visual representations of a spring, and / or other indicia. In one example, the marks can indicate a range of tension on the balloon shaft and / or a range of compression of the spring, such as a first amount of tension / compression, a second amount of tension / compression, and a third amount of tension / compression. In some examples, there can be no marker shown when the spring is not compressed, one marker shown when the spring is partially compressed, and two markers shown when the spring is fully compressed.

[0058] Referring to FIG. 5, 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. This curvature of the steerable section 68 may cause foreshortening of the distal end 68d. This foreshortening may result in an increase in distance between the distal end 68d and the proximal end of the prosthetic valve 12. As the steerable section 68 retracts, some of the compression in the spring 40 relaxes and the spring 40 expands in length to cover the gap. This expansion of the spring helps maintain contact between the distal end of first segment 42 of shaft 22 remains and the proximal end of the prosthetic valve 12 as the prosthetic valve 12, mounted on the balloon 28, is maneuvered around the aortic arch and aligned substantially coaxially within an aortic annulus 30.

[0059] As shown in FIGS. 6-7, 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. 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 maximumdiameter at its proximal end adjacent a distal end 12d of the prosthetic valve 12 (FIG. 6) and tapers in a distal direction toward the nose cone 32.

[0060] 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. 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.

[0061] When the prosthetic valve 12 is at the deployment location, the prosthetic valve 12 is expanded 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. As shown in FIG. 6, prior to inflation of the balloon, the guide catheter shaft 22 (including the first segment 42, the spring 40, and the second segment 44) is withdrawn from the balloon 28. The balloon 28 is then inflated which causes the radial expansion of the prosthetic valve 12.

[0062] FIG. 8 shows a distal end portion of a delivery apparatus 200 according to another example. 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 handle portion 20, a balloon catheter shaft 26, a flex activating member 50, a pull wire 78, etc., and these components are not repeated here for sake of brevity. In some examples, the delivery apparatus 200 may include a distal end portion of the guide catheter shaft 220 may comprise one or more biasing elements (also called biasing members). In the depicted example the biasing element is a coil spring 240 which is coupled to the distal end of the guide catheter shaft 220. When used in combination with a prosthetic valve 12, the distal end of the coil spring 240 abuts the proximal end of the prosthetic valve 12.

[0063] FIG. 9 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.

[0064] 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 R30035 (covered by ASTM F562-02). MP35N™ / UNS R30035 comprises 35% nickel, 35% cobalt, 20% chromium, and 10% molybdenum, by weight.

[0065] 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

[0066] 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

[0067] 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 ofthe 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.

[0068] 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.

[0069] 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.

[0070] 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.

[0071] In all delivery approaches, the delivery apparatus can be advanced over a guide wire 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.

[0072] 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

[0073] 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.

[0074] 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 first section and a second section, and a lumen extending through the first section and the second section; a second shaft having a proximal end portion and a distal end portion, the second shaft extending through the lumen of the first shaft; and one or more biasing elements coupled to and disposed between the first section and the second section of the first shaft, wherein the one or more biasing elements are configured to bias the first section of the firstshaft away from the second section of the first shaft and toward the distal end portion of the second shaft.

[0075] Example 2. The delivery apparatus of any example herein, particularly example 1, further comprising a pull wire extending longitudinally along the first shaft, wherein a distal end of the pull wire is fixed relative to the first shaft, and wherein tension in the pull wire can be adjusted to adjust a curvature of the distal end portion of the first shaft.

[0076] Example 3. The delivery apparatus of any example herein, particularly either example 1 or example 2, further comprising an expansion member coupled to the distal end portion of the second shaft.

[0077] Example 4. The delivery apparatus of any example herein, particularly example 3, wherein the expansion member is an inflatable balloon.

[0078] Example 5. The delivery apparatus of any example herein, particularly any one of examples 1-4, wherein the one or more biasing elements includes a coil compression spring.

[0079] Example 6. An assembly comprising the delivery apparatus of any example herein, particularly any one of examples 3-5 and further comprising an expandable medical implant in a radially compressed state, wherein the expandable medical implant is disposed around the distal end portion of the second shaft.

[0080] Example 7. The assembly of any example herein, particularly example 6, wherein the one or more biasing elements is in a compressed state between the distal end of the first shaft and a proximal end of the expandable medical implant such that the first section of the first shaft applies a distally-directed force to the proximal end of the expandable implant.

[0081] Example 8. The assembly of any example herein, particularly example 7, wherein the one or more biasing elements is configured to move from a compressed state to an expanded state to maintain the first section of the first shaft against the proximal end of the expandable medical implant as the expandable medical implant is advanced to the implantation location.

[0082] Example 9. The assembly of any example herein, particularly example 8, wherein the one or more biasing elements moves between the compressed state and the expanded state as a curvature of the first shaft changes.

[0083] Example 10. The assembly of any example herein, particularly any one of examples 6-9, wherein the medical implant comprises a prosthetic heart valve, a stent, or a support structure for a prosthetic heart valve.

[0084] Example 11. An assembly for delivering a medical implant to an implant location, comprising: a delivery apparatus comprising: an inner catheter shaft having a proximal end portion and a distal end portion; an expandable balloon disposed on the distal end portion of the inner catheter shaft; an outer catheter shaft having a first section extending proximally from a distal end of the outer shaft and a second section disposed proximal relative to the first section; a one or more biasing members coupled to the first section of the outer shaft and the second section of the outer shaft; and an expandable implant disposed around the expandable balloon having a proximal end portion and a distal end portion, wherein the one or more biasing members are movable between a compressed state and an expanded state, wherein in the compressed state and in the expanded state, the one or more biasing members urge the distal end of the outer shaft against the proximal end of the expandable implant.

[0085] Example 12. The assembly of any example herein, particularly example 11, wherein the wherein the one or more biasing members includes a coil compression spring.

[0086] Example 13. The assembly of any example herein, particularly any one of examples 11-12, further comprising a pull wire extending longitudinally along the second section of the outer catheter shaft, wherein a distal end of the pull wire is fixed relative to the second section, wherein tension in the pull wire can be adjusted to adjust a curvature of a distal end portion of the second section of the outer catheter shaft.

[0087] Example 14. The assembly of any example herein, particularly any one of examples 11-13, wherein the medical implant comprises a prosthetic heart valve.

[0088] Example 15. The assembly of any example herein, particularly example 14, wherein the prosthetic heart valve comprises an annular frame and a plurality of leaflets coupled to and disposed within the frame.

[0089] Example 16. The delivery apparatus or assembly of any example herein, particularly any one of examples 1-15, wherein the delivery apparatus or system is sterilized.

[0090] Example 17. A method of implanting a medical implant, comprising: introducing a delivery apparatus into a patient’s body; and adjusting tension in a pull wire of the deliveryapparatus to steer the delivery apparatus through the patient’s vasculature, wherein adjusting the tension in the pull wire results in one or more biasing members of the delivery apparatus expanding from a compressed state to an expanded state to maintain a distal end of a first shaft in contact with a proximal end of the medical implant.

[0091] Example 18. The method of any example herein, particularly example 17, further comprising advancing a distal end portion of the delivery device towards an implant location until the medical implant is within or adjacent to a desired implant position.

[0092] Example 19. The method of any example herein, particularly either example 17 or example 18, further comprising inflating a balloon, wherein inflating the balloon results in radial expansion of the medical implant.

[0093] Example 20. The method of any example herein, particularly any one of examples 17-19, wherein prior to introducing a delivery device into the body of a patient the method further comprises, moving the one or more biasing members from the expanded state to the compressed state by moving the first shaft of the delivery apparatus relative to a second shaft of the delivery apparatus.

[0094] Example 21. The method of any example herein, particularly any one of examples 17-20, wherein the medical implant is a prosthetic heart valve, and the method further comprises advancing the distal end portion of the delivery device through the patient’ s aorta until the medical implant is within or adjacent to the patient’s native aortic valve.

[0095] Example 22. The method of any example herein, particularly any one of examples 17-21, wherein the steps are performed on a living animal or on a simulation.

[0096] Example 23. A delivery apparatus for delivering a medical implant to an implantation location within a patient’s body, the delivery apparatus comprising: a shaft having a proximal end portion and a distal end portion; and a biasing element coupled to the distal end portion and coaxial with the shaft.

[0097] 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 of the features of one locking mechanism can be combined with any one or more features of another locking mechanism. As another example, any oneor more features of one delivery apparatus can be combined with any one or more features of another delivery apparatus.

[0098] 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 first section and a second section, and a lumen extending through the first section and the second section; a second shaft having a proximal end portion and a distal end portion, the second shaft extending through the lumen of the first shaft; and one or more biasing elements coupled to and disposed between the first section and the second section of the first shaft, wherein the one or more biasing elements are configured to bias the first section of the first shaft away from the second section of the first shaft and toward the distal end portion of the second shaft.

2. The delivery apparatus of claim 1, further comprising a pull wire extending longitudinally along the first shaft, wherein a distal end of the pull wire is fixed relative to the first shaft, and wherein tension in the pull wire can be adjusted to adjust a curvature of the distal end portion of the first shaft.

3. The delivery apparatus of any one of claims 1-2, further comprising an expansion member coupled to the distal end portion of the second shaft.

4. The delivery apparatus of claim 3, wherein the expansion member is an inflatable balloon.

5. The delivery apparatus of any one of claims 1-4, wherein the one or more biasing elements includes a coil compression spring.

6. An assembly comprising the delivery apparatus of any one of claims 3-5 and further comprising an expandable medical implant in a radially compressed state, wherein the expandable medical implant is disposed around the distal end portion of the second shaft.

7. The assembly of claim 6, wherein the one or more biasing elements is in a compressed state between the distal end of the first shaft and a proximal end of theexpandable medical implant such that the first section of the first shaft applies a distally- directed force to the proximal end of the expandable implant.

8. The assembly of claim 7, wherein the one or more biasing elements is configured to move from a compressed state to an expanded state to maintain the first section of the first shaft against the proximal end of the expandable medical implant as the expandable medical implant is advanced to the implantation location.

9. The assembly of claim 8, wherein the one or more biasing elements moves between the compressed state and the expanded state as a curvature of the first shaft changes.

10. The assembly of any one of claims 6-9, wherein the medical implant comprises a prosthetic heart valve, a stent, or a support structure for a prosthetic heart valve.

11. An assembly for delivering a medical implant to an implant location, comprising: a delivery apparatus comprising: an inner catheter shaft having a proximal end portion and a distal end portion; an expandable balloon disposed on the distal end portion of the inner catheter shaft; an outer catheter shaft having a first section extending proximally from a distal end of the outer shaft and a second section disposed proximal relative to the first section; one or more biasing members coupled to the first section of the outer shaft and the second section of the outer shaft; and an expandable implant disposed around the expandable balloon having a proximal end portion and a distal end portion, wherein the one or more biasing members are movable between a compressed state and an expanded state, wherein in the compressed state and in the expanded state, the one or more biasing members urge the distal end of the outer shaft against the proximal end of the expandable implant.

12. The assembly of claim 11, wherein the one or more biasing members includes a coil compression spring.

13. The assembly of any one of claims 11-12, further comprising a pull wire extending longitudinally along the second section of the outer catheter shaft, wherein a distal end of the pull wire is fixed relative to the second section, wherein tension in the pull wire can be adjusted to adjust a curvature of a distal end portion of the second section of the outer catheter shaft.

14. The assembly of any one of claims 1 1 -13, wherein the medical implant comprises a prosthetic heart valve.

15. The assembly of claim 14, wherein the prosthetic heart valve comprises an annular frame and a plurality of leaflets coupled to and disposed within the frame.

16. A method of implanting a medical implant, comprising: introducing a delivery apparatus into a patient’s body; and adjusting tension in a pull wire of the delivery apparatus to steer the delivery apparatus through the patient’s vasculature, wherein adjusting the tension in the pull wire results in one or more biasing members of the delivery apparatus expanding from a compressed state to an expanded state to maintain a distal end of a first shaft in contact with a proximal end of the medical implant.

17. The method of claim 16, further comprising advancing a distal end portion of the delivery apparatus towards an implant location until the medical implant is within or adjacent to a desired implant position.

18. The method of any one of claims 16-17, further comprising inflating a balloon, wherein inflating the balloon results in radial expansion of the medical implant.

19. The method of any one of claims 16-18, wherein prior to introducing a delivery device into the body of a patient the method further comprises, moving the one or more biasing members from the expanded state to the compressed state by moving the first shaft of the delivery apparatus relative to a second shaft of the delivery apparatus.

20. The method of any one of claims 16-19, wherein the medical implant is a prosthetic heart valve, and the method further comprises advancing the distal end portion of the delivery device through the patient’s aorta until the medical implant is within or adjacent to the patient’ s native aortic valve.

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