Patent Application
20200375733
Not Applicable
The invention relates to devices, systems and features for loading, delivering, positioning and repositioning a stent in a body. More specifically, an expandable and collapsible prosthetic heart valve device is delivered and positioned within a heart chamber, preferably transseptally to the left atrium.
The human heart comprises four chambers and four heart valves that assist in the forward (antegrade) flow of blood through the heart. The chambers include the left atrium, left ventricle, right atrium and right ventricle. The four heart valves include the mitral valve, the tricuspid valve, the aortic valve and the pulmonary valve. See generally
The mitral valve is located between the left atrium and left ventricle and helps control the flow of blood from the left atrium to the left ventricle by acting as a one-way valve to prevent backflow into the left atrium. Similarly, the tricuspid valve is located between the right atrium and the right ventricle, while the aortic valve and the pulmonary valve are semilunar valves located in arteries flowing blood away from the heart. The valves are all one-way valves, with leaflets that open to allow forward (antegrade) blood flow. The normally functioning valve leaflets close under the pressure exerted by reverse blood to prevent backflow (retrograde) of the blood into the chamber it just flowed out of. For example, the mitral valve when working properly provides a one-way valving between the left atrium and the left ventricle, opening to allow antegrade flow from the left atrium to the left ventricle and closing to prevent retrograde flow from the left ventricle into the left atrium. This retrograde flow, when present, is known as mitral regurgitation or mitral valve regurgitation.
Native heart valves may be, or become, dysfunctional for a variety of reasons and/or conditions including but not limited to disease, trauma, congenital malformations, and aging. These types of conditions may cause the valve structure to fail to close properly resulting in regurgitant retrograde flow of blood from the left ventricle to the left atrium in the case of a mitral valve failure.
Mitral valve regurgitation is a specific problem resulting from a dysfunctional mitral valve that allows at least some retrograde blood flow back into the left atrium from the right atrium. In some cases, the dysfunction results from mitral valve leaflet(s) that prolapse up into the left atrial chamber, i.e., above the upper surface of the annulus instead of connecting or coapting to block retrograde flow. This backflow of blood places a burden on the left ventricle with a volume load that may lead to a series of left ventricular compensatory adaptations and adjustments, including remodeling of the ventricular chamber size and shape, that vary considerably during the prolonged clinical course of mitral regurgitation.
Regurgitation can be a problem with native heart valves generally, including tricuspid, aortic and pulmonary valves as well as mitral valves.
Native heart valves generally, e.g., mitral valves, therefore, may require functional repair and/or assistance, including a partial or complete replacement. Such intervention may take several forms including open heart surgery and open heart implantation of a replacement heart valve. See e.g., U.S. Pat. No. 4,106,129 (Carpentier), for a procedure that is highly invasive, fraught with patient risks, and requiring not only an extended hospitalization but also a highly painful recovery period.
Less invasive methods and devices for replacing a dysfunctional heart valve are also known and involve percutaneous access and catheter-facilitated delivery of the replacement valve. Most of these solutions involve a replacement heart valve attached to a structural support such as a stent, commonly known in the art, or other form of wire network designed to expand upon release from a delivery catheter. See, e.g., U.S. Pat. No. 3,657,744 (Ersek); U.S. Pat. No. 5,411,552 (Andersen). The self-expansion variants of the supporting stent assist in positioning the valve, and holding the expanded device in position, within the subject heart chamber or vessel. This self-expanded form also presents problems when, as is often the case, the device is not properly positioned in the first positioning attempt and, therefore, must be recaptured and positionally adjusted. This recapturing process in the case of a fully, or even partially, expanded device requires re-collapsing the device to a point that allows the operator to retract the collapsed device back into a delivery sheath or catheter, adjust the inbound position for the device and then re-expand to the proper position by redeploying the positionally-adjusted device distally out of the delivery sheath or catheter. Collapsing the already expanded device is difficult because the expanded stent or wire network is generally designed to achieve the expanded state which also resists contractive or collapsing forces.
Besides the open heart surgical approach discussed above, gaining access to the valve of interest is achieved percutaneously via one of at least the following known access routes: transapical; transfemoral; transatrial; and trans septal delivery techniques.
Generally, the art is focused on systems and methods that, using one of the above-described known access routes, allow a partial delivery of the collapsed valve device, wherein one end of the device is released from a delivery sheath or catheter and expanded for an initial positioning followed by full release and expansion when proper positioning is achieved. See, e.g., U.S. Pat. No. 8,852,271 (Murray, III); U.S. Pat. No. 8,747,459 (Nguyen); U.S. Pat. No. 8,814,931 (Wang); U.S. Pat. No. 9,402,720 (Richter); U.S. Pat. No. 8,986,372 (Murray, III); and U.S. Pat. No. 9,277,991 (Salahieh); and U.S. Pat. Pub. Nos. 2015/0272731 (Racchini); and 2016/0235531 (Ciobanu).
In addition, all known prosthetic heart valves are intended for full replacement of the native heart valve. Therefore, these replacement heart valves, and/or anchoring or tethering structures, physically extend out of the left atrial chamber, in the case of mitral valves, and engage the inner annulus and/or valve leaflets, in many cases pinning the native leaflets against the walls of the inner annulus, thereby permanently eliminating all remaining functionality of the native valve and making the patient completely reliant on the replacement valve. In other cases, the anchoring structures extend into the left ventricle and may anchor into the left ventricle wall tissue and/or the sub-annular surface at the top of the left ventricle. Others may comprise a presence in, or engagement with, a pulmonary artery.
Obviously, there will be cases when native valve has lost virtually complete functionality before the interventional implantation procedure. In this case the preferred solution will comprise an implant that does not extent outside of, e.g., the left atrium, and that functions to completely replace the native valve function. However, in many other cases, the native valve remains functional to an extent and may, or may not, continue to lose functionality after the implantation procedure. A preferred solution in this case comprises delivery and implantation of a valve device that will function both as a supplemental or augmentation valve without damaging the native leaflets in order to retain native valve leaflet functionality as long as present, while also being fully capable of replacing the native function of a valve that slowly loses most or all of its functionality post-implantation of the prosthetic valve.
Delivery systems, devices and methods for prosthetic heart valve devices are known, but require improvement. In particular, known transseptal delivery systems, devices and methods can be improved on, including but not limited to: the collapsing/loading of the prosthetic heart valve device into the lumen of a delivery catheter; the release and orientation of the expanding prosthetic heart valve device from the distal end of the delivery catheter's lumen into the heart chamber, and oriented positioning within the heart chamber. Known delivery systems, devices, and methods also still suffer from significant flaws in delivery methodology including, inter alia, recapture capability and efficiency to enable repositioning as needed to achieve optimal locating and sealing.
Various embodiments of the several inventions disclosed herein address these, inter alia, issues.
The present invention provides methods, devices, and systems for improved collapsing/loading of a prosthetic heart valve device into a lumen of a delivery catheter; improved release and orientation of the expanding prosthetic heart valve device from the distal end of the delivery catheter's lumen into a heart chamber, and improvements in oriented positioning of the device within the heart chamber. The methods, devices, and systems of the present disclosure also provide improved capability and efficiency of recapturing a delivered prosthetic heart valve device to enable repositioning, as needed, to achieve optimal locating and sealing of the device at the desired treatment site. These improvements may be at least partially achieved by a stent cap affixed to a top portion of a stent of a prosthetic valve device and configured for engagement and disengagement with a male engagement member, the male engagement member in turn being configured for engagement and disengagement with a manipulable torque wire that enables positioning, release, recapture, and repositioning of the prosthetic valve device via the male engagement member and the stent cap.
In one embodiment, a loading, delivery, deployment and positioning system for an expandable and collapsible prosthetic heart valve device having a stent outer frame with a top and a bottom, wherein the bottom defines an outflow region therefrom, the prosthetic heart valve device biased to expand and adapted to collapse into the lumen of a delivery catheter, comprises a torque wire having a length that is longer than a length of the delivery catheter and adapted to translate and/or rotate within the delivery catheter lumen when a distal end of the torque wire is manipulated by an operator and wherein the torque wire comprises a threaded region at its distal end; a stent cap non-rotationally attached at or near the top of the stent outer frame, the stent cap defining a channel and a pair of lateral locking grooves therethrough, wherein the channel is defined continuously with the lateral locking grooves; a male engagement member comprising: a threaded region at a proximal end, the threaded region adapted to threadingly engage the threaded region of the torque wire, a stem region extending distally from the threaded region; and left and right engagement handles extending laterally from a distal end of the stem region, wherein the left and right engagement handles are adapted to detachably engage the stent cap.
In another embodiment, a method for loading, delivery, deployment and positioning a system for an expandable and collapsible prosthetic heart valve device comprises providing the system of the one embodiment described above; threadingly attaching the male engagement member to the torque wire; removably attaching the male engagement member to the stent cap; pulling the torque wire through the lumen of the delivery catheter in a proximal direction; pulling the expanded prosthetic heart valve device into the distal end of the delivery catheter lumen and thereby collapsing the prosthetic heart valve device therein; locating and loading the collapsed prosthetic heart valve device within the delivery catheter lumen; accessing the patient's heart chamber with the distal end of the delivery catheter; pushing with the torque wire the collapsed prosthetic heart valve device out of the distal end of the delivery catheter, whereby the prosthetic heart valve device biasingly expands; rotating and/or otherwise turning the torque wire to direct and position the expanding prosthetic heart valve device within the heart chamber; disconnecting the male engagement member from the stent cap; withdrawing the torque wire and attached male engagement member into the lumen of the delivery catheter; and withdrawing the delivery catheter from the patient's body.
Certain inventive embodiments described herein are readily applicable to single or two chamber solutions, unless otherwise indicated. Moreover, certain embodiments discussed herein may be applied to preservation and/or replacement of native valve functionality generally, and are not, therefore, limited to prosthetic mitral valve devices but may be extended to include prosthetic tricuspid valve devices, prosthetic aortic devices, prosthetic pulmonary valves, and methods for the loading, delivery, deployment, and positioning of any such valves.
The description of the invention and its applications as set forth herein is illustrative and is not intended to limit the scope of the invention. Features of various embodiments may be combined with other embodiments within the contemplation of this invention. Variations and modifications of the embodiments disclosed herein are possible, and practical alternatives to and equivalents of the various elements of the embodiments would be understood to those of ordinary skill in the art upon study of this patent document. These and other variations and modifications of the embodiments disclosed herein may be made without departing from the scope and spirit of the invention.
While the invention is amenable to various modifications and alternative forms, specifics thereof are shown by way of example in the drawings and described in detail herein. It should be understood, however, that the intention is not to limit the invention to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.
Generally, various embodiments of the present invention are directed to devices and methods for optimizing delivery of a prosthetic heart valve device comprising a collapsible and expandable frame, e.g., a stent or other collapsible and expandable device. The embodiments described herein optimize delivery of a prosthetic heart valve device by (1) reducing loading forces during collapsing and translating through the delivery catheter lumen; and/or (2) by reducing, minimizing or eliminating air introduction into the system comprising the prosthetic heart valve device and/or the lumen of the delivery catheter. The embodiments described herein also provide improved capability and efficiency of recapturing a delivered prosthetic heart valve device to enable repositioning, as needed, to achieve optimal locating and sealing of the device at the desired treatment site.
The device 10 further includes a valve support 24 that contains prosthetic leaflet(s) (not shown) and provides a flow channel for blood flow through the stent 12 to the outflow region 16. When implanted, the valve support 24 is adapted to substantially align with an annulus and allow one-way, antegrade blood flow therethrough while preventing retrograde blood flow as a result of the prosthetic leaflet(s) supported therein.
The valve support 24 may be wholly contained within the interior of the stent 12 or may extend at least partially out of the stent 12 in the downstream (outflow) direction. Still more alternatively, the valve support 24 may extend completely outwardly from the stent 12, and not extend radially into the interior of the stent 12. As shown in
The stent cap 20 preferably may be affixed to the stent 12 at the midline or longitudinal axis of the prosthetic heart valve device 10, though other locations proximate the top portion 18 of the frame of stent 12 are also possible and within the inventive scope of the present disclosure.
As shown in
The stent cap 20 comprises a cap body 36 that defines an access channel 32 therethrough. When the stent cap 20 is affixed to the stent 12, the access channel 32 is spaced apart from struts 30 of the stent 12 to enable unimpeded access of a male engagement member to the channel 32. The access channel 32 merges into lateral locking grooves 34A and 34B, which are also defined by the cap body 36. The lateral locking grooves 34A and 34B comprise a radial (the largest) diameter that is larger than the radial diameter of the access channel 32. In another embodiment, the center of the stent cap 20 may include a female threaded attachment that allows for engagement of a male threaded component of a male engagement member thereto. As with other embodiments, embodiment in which the center of the stent cap 20 includes a female threaded attachment advantageously may enable loading of a prosthetic heart valve device (e.g. device 10) into a delivery catheter, transseptal deployment of the prosthetic heart valve device, and repositioning of the prosthetic heart valve device as needed.
In embodiments in which the center of the stent cap 20 includes a female threaded attachment, the male engagement member 40 may include a second male threaded region at the distal end of the male engagement member 40. In some such embodiments, the threaded region 42 at the proximal end of the male engagement member 40 and the second male threaded region at the distal end of the male engagement member 40 may be threaded in opposite directions (i.e. one having right-hand threading and the other having left-hand threading). In this manner the male engagement member 40 may be unscrewed from the female threaded attachment of the stent cap 20 to release of the stent cap 20 from the male engagement member 40 without unscrewing the threaded region 42 from a torque wire (described with respect to
As further shown in the embodiment of
Moreover, the line drawn from the center of the left and right engagement handles 44A, 44B and perpendicular thereto, as shown, may be non-parallel to, and therefore intersecting with, a line running through the central axis of the threaded region 42, with a predetermined angle of offset, represented as μ. Alternatively, the perpendicular line to the left and right engagement handles 44A, 44B and the line through the central axis of the threaded region 42 may be parallel with each other. Still more alternatively, the perpendicular line, drawn in the center of the handle region 44 between the left and right engagement handles 44A, 44B, may be collinear with the line through the central axis of the threaded region 42. In any such embodiments, the various curvatures of the stem region 46 of the male engagement member 40 advantageously may assist or enable downward turning and/or other directional manipulation of the prosthetic heart valve device 10 during delivery of the device 10.
As shown in
Applicant has found that the torque wire 50 provides necessary tensile strength for not only pushing and pulling of the prosthetic heart valve device 10, but also for translatable rotation of the prosthetic heart valve device 10 initiated from the proximal handle end of the torque wire 50 to optimize positioning of the prosthetic heart valve device 10 within the heart chamber. Once the prosthetic heart valve device 10 is connected with the torque wire 50 in this manner, the expanded stent 12 may be collapsingly loaded into the lumen of the delivery catheter 52 by retracting or pulling the torque wire 50 distally. Similarly, after expanded delivery of the prosthetic heart valve device 10 into the heart chamber, the prosthetic heart valve device 10 may be resheathed into the lumen of the delivery catheter 52 by pulling the torque wire 50 distally. The stent cap 20 may be translated when the bottom portion 14 of the body of the stent 12, i.e., the portion comprising the valve support 24, is engaged with the anatomy of the patient at the treatment site.
Additionally, or alternatively, to the balloon 62 disposed on the guide wire 60, the delivery catheter 52 may be used to deliver a tapered dilation member 64, which may be disposed on a corresponding catheter 66 as is well-known in the art, through the lumen of the delivery catheter 52, as shown in
Next, as shown in
When the prosthetic heart valve device 10 is properly positioned in the exemplary left atrium, the torque wire 50 is then manipulated by the operator to disengage the male engagement member 40, as discussed with respect to
In some instances, it may be desirable to recapture the prosthetic valve device 10 after it has been delivered out of the lumen of the delivery catheter 52, either before or after the male engagement member 40 has been disconnected from the stent cap 20. For example, an operator delivering the prosthetic valve device 10 may determine that the device 10 is not approaching the mitral annulus at a desired angle, or that the device 10 is not properly located or seated at the mitral annulus. In instances in which the male engagement member 40 has not yet been disconnected from the stent cap 20 when this determination is made, recapture of the expanded device 10 may be achieved by distally pulling back the expanded device 10 with a distal proximal pulling of the torque wire 50 into the lumen of the delivery catheter 52 for controlled collapse of the device 10 therein. Alternatively, if the male engagement member 40 has been disconnected from the stent cap 20 when this determination is made, then the stent cap 20 may be reengaged with the male engagement member 40, as described above, for recapture. Reengagement of the stent cap 20 with the male engagement member 40 may be achieved using known visualization techniques; e.g., fluoroscopy, to guide recapture. Thus, in some embodiments, one or more portions of the male engagement member 40 and/or the stent cap 20 may include a radiopaque material.
In all embodiments, when the collapsed prosthetic heart valve device 10 is “loaded” within the lumen of the delivery catheter 52, it may be delivered via the delivery catheter 52 through the patient's vasculature to the heart chamber of interest using any acceptable access route and/or delivery technique, including but not limited to: transapical; transfemoral; transatrial; and transseptal delivery techniques, using the devices and systems and methods described above.
The skilled artisan will understand that the embodiments of the inventions described above may be used to improve implant loading of a prosthetic heart valve device into a delivery catheter, translation of the device through the lumen of a delivery catheter, controlled release of the device from the delivery catheter, positioning and locating of the expanding/expanded device in the subject heart chamber, repositioning and relocating of the device in the heart chamber, and/or recapturing and recollapsing of the device once expanded in the heart chamber.
The description of the invention and its applications as set forth herein is illustrative and is not intended to limit the scope of the invention. Features of various embodiments may be combined with other embodiments within the contemplation of this invention. Variations and modifications of the embodiments disclosed herein are possible, and practical alternatives to and equivalents of the various elements of the embodiments would be understood to those of ordinary skill in the art upon study of this patent document. These and other variations and modifications of the embodiments disclosed herein may be made without departing from the scope and spirit of the invention.
This application claims the benefit of U.S. Provisional Application No. 62/854,584, filed May 30, 2019 and entitled DEVICES, SYSTEMS AND METHODS FOR COLLAPSIBLE AND EXPANDABLE IMPLANT LOADING, TRANSSEPTAL DELIVERY, POSITIONING DEPLOYMENT AND REPOSITIONING DEPLOYMENT, the entirety of which is hereby incorporated by reference.
| Number | Date | Country | |
|---|---|---|---|
| 62854584 | May 2019 | US |
