Patent Application
20240277402
Valvular heart disease, and specifically aortic and mitral valve disease, is a significant health issue in the United States. Valve replacement is one option for treating heart valve diseases. Prosthetic heart valves, including surgical heart valves and collapsible/expandable heart valves intended for transcatheter aortic valve replacement (“TAVR”) or transcatheter mitral valve replacement (“TMVR”), are well known in the patent literature. Surgical or mechanical heart valves may be sutured into a native annulus of a patient during an open-heart surgical procedure, for example. Collapsible/expandable heart valves may be delivered into a patient via a tube-like delivery apparatus such as a catheter, a trocar, a laparoscopic instrument, or the like to avoid a more invasive procedure such as full open-chest, open-heart surgery. As used herein, reference to a “collapsible/expandable” heart valve includes heart valves that are formed with a small cross-section that enables them to be delivered into a patient through a tube-like delivery apparatus in a minimally invasive procedure, and then expanded to an operable state once in place, as well as heart valves that, after construction, are first collapsed to a small cross-section for delivery into a patient and then expanded to an operable size once in place in the valve annulus.
Collapsible/expandable prosthetic heart valves typically take the form of a one-way valve structure (often referred to herein as a valve assembly) mounted to/within an expandable stent. In general, these collapsible/expandable heart valves include a self-expanding or balloon-expandable stent, often made of nitinol or another shape-memory metal or metal alloy (for self-expanding stents) or steel or cobalt chromium (for balloon-expandable stents). Existing collapsible/expandable TAVR devices have been known to use different configurations of stent layouts-including straight vertical struts connected by “V”s as illustrated in U.S. Pat. No. 8,454,685, or diamond-shaped cell layouts as illustrated in U.S. Pat. No. 9,326,856, both of which are hereby incorporated herein by reference. The one-way valve assembly mounted to/within the stent includes one or more leaflets, and may also include a cuff or skirt. The cuff may be disposed on the stent's interior or luminal surface, its exterior or abluminal surface, and/or on both surfaces. A cuff helps to ensure that blood does not flow around the valve leaflets if the valve or valve assembly is not optimally seated in a valve annulus. A cuff, or a portion of a cuff, disposed on the exterior of the stent can help retard leakage around the outside of the valve (the latter known as paravalvular or “PV” leakage).
Balloon expandable valves are typically delivered to the native annulus while collapsed (or “crimped”) onto a deflated balloon of a balloon catheter, with the collapsed valve being either covered or uncovered by an overlying sheath. Once the crimped prosthetic heart valve is positioned within the annulus of the native heart valve that is being replaced, the balloon is inflated to force the balloon expandable valve to transition from the collapsed or crimped condition into an expanded or deployed condition, with the prosthetic heart valve tending to remain in the shape into which it is expanded by the balloon. Typically, when the position of the collapsed prosthetic heart valve is determined to be in the desired position relative to the native annulus (e.g. via visualization under fluoroscopy), a fluid (typically a liquid although gas could be used as well) such as saline is pushed via a syringe (manually, automatically, or semi-automatically) through the balloon catheter to cause the balloon to begin to fill and expand, and thus cause the overlying prosthetic heart valve to expand into the native annulus.
There are several complications when implanting a prosthetic heart valve. For example, in the case of mitral valve repair, long, untethered, floppy anterior mitral leaflets (AMLs) represent an increased risk for systolic anterior motion (SAM) and consequent left ventricular outflow track obstruction in mitral valve replacement therapies. In some cases, around 10% of patients sent for assessment of certain mitral valve implantations are declined due to having an increased risk of developing systolic anterior motion and associated left ventricular outflow tract (LVOT) obstruction. On other occasions, a patient may be initially cleared for mitral valve replacement, but a risk develops between the time the patient was initially screened and the implantation timeframe as patient anatomy changes (e.g., chords rupture or elongate), and at the day of the procedure the physician may see an ad-hoc need for AML laceration to prevent SAM/LVOT obstruction.
Currently, the only procedure available to mitigate or prevent SAM is LAMPOON, a procedure in which AML is lacerated using traditional wires and catheters. A conventional LAMPOON procedure needs to be planned for in advance to valve implantation, and essentially be conducted prior a mitral valve replacement (e.g., a TENDYNE™ TMVI). However, this procedure is quite long, technically demanding for the surgeon, and is not always successful. In addition, since a LAMPOON procedure must be performed prior to implantation, any unpredictability of the anatomy's response to valve implantation poses additional risk of an unfavorable outcome. Some other LAMPOON procedures may be performed in valve-in-MAC or ring, or valve-in-valve procedures after the implantation as a bailout procedure. These also utilize traditional wires and/or catheters.
The disclosed device may be adapted further with a forward cutting orientation to alternatively be used to perform the BASILICA technique with a retrograde approach. In this other application, the cutting tool would lacerate aortic valve leaflets that obstruct coronary arteries after TAVI implantation.
Among other advantages, it would be beneficial to provide new tools to achieve consistent and simpler leaflet laceration similar to LAMPOON or BASILICA procedures.
In some embodiments, a leaflet laceration device, includes an elongated shaft, a moveable arm coupled to the elongated shaft and pivotable relative thereto between an open condition and a closed condition, and a cutting element coupled to at least one of the elongated shaft and the moveable arm, the cutting element being configured and arranged to contact a first surface of an anterior mitral leaflet.
In some examples, a method of treatment, includes providing a leaflet laceration device including an elongated shaft, a moveable arm coupled to the elongated shaft and pivotable relative thereto between an open condition and a closed condition, and a cutting element coupled to at least one of the elongated shaft and the moveable arm, advancing the leaflet laceration device to an anterior mitral leaflet, and cutting the anterior mitral leaflet with the cutting element.
As used herein, the term “inflow end” when used in connection with a prosthetic heart valve refers to the end of the prosthetic valve into which blood first enters when the prosthetic valve is implanted in an intended position and orientation, while the term “outflow end” refers to the end of the prosthetic valve where blood exits when the prosthetic valve is implanted in the intended position and orientation. Thus, for a prosthetic aortic valve, the inflow end is the end nearer the left ventricle while the outflow end is the end nearer the aorta. For a prosthetic mitral valve, the inflow end is adjacent the atrium while the outflow end is the adjacent the ventricle. The intended position and orientation are used for the convenience of describing the valve disclosed herein, however, it should be noted that the use of the valve is not limited to the intended position and orientation, but may be deployed in any type of lumen or passageway. For example, although the prosthetic heart valve is described herein as a prosthetic aortic valve, the same or similar structures and features can be employed in other heart valves, such as the pulmonary valve, the mitral valve, or the tricuspid valve, and it will be understood that”. Further, the term “proximal,” when used in connection with a delivery device or system, refers to a direction relatively close to the user of that device or system when being used as intended, while the term “distal” refers to a direction relatively far from the user of the device. In other words, the leading end of a delivery device or system is positioned distal to a trailing end of the delivery device or system, when being used as intended. As used herein, the terms “substantially,” “generally,” “approximately,” and “about” are intended to mean that slight deviations from absolute are included within the scope of the term so modified. As used herein, the stent may assume an “expanded state” and a “collapsed state,” which refer to the relative radial size of the stent.
The present disclosure provides several systems, devices and methods to cut, lacerate, separate or notch a native valve leaflet. The devices and systems described herein may provide a standardized, precise, safe, and fast anterior mitral leaflet laceration procedure that can be performed by unexperienced users (e.g., those inexperienced with LAMPOON and BASILICA procedures). Currently available LAMPOON techniques are complex and long procedures that require thorough preparation of the catheters and the wires used before physicians are ready to lacerate anterior mitral leaflet. In addition, experienced imaging and wire maneuvers are required, and an optimal outcome may not always be possible due to a wide range of anatomic challenges. In a LAMPOON procedure, a native leaflet is first punctured, which may be difficult due to leaflet motion or lack of support. The procedure relies on wires, which may be imprecise and may take multiple attempts before success-a great deal of skill and experience is required to successfully puncture a leaflet. Once the puncture is complete, adjustment of the cutting location is not possible. If the first cut was not long enough (e.g., puncture position was too close to edge of leaflet), then it may be impossible to extend the cut with a second attempt. Additionally, it is often difficult to gauge whether the procedure was successful. Experienced sites need roughly an hour and thirty minutes for a LAMPOON procedure, and this timeframe may be significantly longer in challenging cases. Additionally, as mentioned previously, one of the major disadvantages of a conventional procedure, is that it must be pre-operatively determined which patients have to undergo anterior mitral leaflet laceration using LAMPOON, before a prosthetic mitral valve (e.g., TENDYNE™ valve) can be implanted.
Having a device specialized to resolve the above-described challenges (e.g., SAM and SAM-related LVOT obstruction), would make leaflet laceration more reproducible, precise, efficient, and shorter. In addition, the disclosed cutting tool and technique is intended to offer the user the ability to perform and/or revise cutting in advance of a valve replacement, or after valve replacement implantation has occurred to better optimize outcomes with valve implantation. While TENDYNE™ TMVI has been noted, the disclosed laceration catheter may be used to improve SAM-related LVOT obstruction outcomes for any mitral valve replacement device including transapical, transseptal, or surgical devices).
When obstruction is present or expected, as shown in
To resolve, or prevent, this complication, the anterior mitral leaflet 15 may be cut, lacerated or resected as shown in
A leaflet laceration device having electrosurgical and/or mechanical laceration capabilities may be used. The leaflet laceration device may allow users to perform laceration of an anterior mitral leaflet using a transapical approach, a transeptal approach before or after valve implantation, or alternatively, retrograde laceration via the aorta before or after valve implantation.
In
Thus, three different feasible approaches (e.g., trans-septal, trans-arterial, and transapical) are disclosed in order to lacerate/cut the anterior mitral leaflet, and each of these approaches has its own advantage. For example, the transapical approach of
In terms of specific benefits, the currently disclosed device and/or approaches may allow or encourage new, less experienced, sites to lacerate anterior mitral leaflets in high-risk SAM patients before a prosthetic valve replacement procedure, and may provide sites a bailout option in case pre-assessment was not entirely accurate and a patient intraoperatively develops SAM. This is particularly beneficial as exact exclusion criteria for patients or AMLs which could possibly develop SAM and LVOT obstruction are not perfectly defined. Thus, having a bailout option is reassuring for many (less experienced) sites and provides flexibility to all prosthetic valve implanters to optimize outcomes without concern for LVOT obstruction.
More specifically, some of the biggest advantages of currently disclosed device and/or approaches include maneuverability, precision, grasping and/or timing. First, maneuverability (e.g., the possibility to grasp an anterior mitral leaflet from different directions and orientations) is of high importance due to anatomical characteristics of each patient. In some instances, it may be desirable to lacerate the anterior mitral leaflet closer to the lateral commissure as sometimes the aorta is positioned laterally. Second, the instant disclosure aims to improve precision and the ability to repeatably lacerate the desired length of the leaflet without cutting too much or too little while avoiding damage to any other anatomical structures (e.g., chords, papillary muscles, and annulus). Because leaflets may vary in length, the depth/length of the laceration/cut may need to be adjusted during the procedure for unique anatomies, and for how an anatomy responds while being lacerated. Third, improved grasping of a native leaflet may provide stability of the leaflet during the laceration/cutting. Finally, the procedure length may be shortened than a traditional procedure.
In some examples, the outer sheath 410 is long enough to cross the aortic arch via transfemoral access. This may allow the physician to easily track the device to the annulus and allow navigation anteriorly and/or posteriorly within the annulus. One or more pull wires 411 may couple to the distal end of the sheath 410 and extend toward the handle 440 to allow the physician to control the sheath (e.g., to actively flex or bend it through the aortic arch). Within outer sheath 410, the inner catheter 420 may also easily track the anatomy and translate and/or rotate independently within the sheath 410. The deflectable section or hinge point 426 at arrow 425 may allow the cutting assembly to deflect parallel to the annular plane for leaflet grasping. In some examples, inner catheter 420 has one or more pull wires 422 running through it from its distal end to handle 440 that allow the physician to actuate the cutting assembly from the handle 440.
In a third example, shown in
In a fourth example, shown in
In use, the surgeon may perform a leaflet laceration procedure using either the mechanical or an electrosurgical variation. In either case, the medical instrument may be advanced to the target site via one of the approaches suggest in
It is to be understood that the embodiments described herein are merely illustrative of the principles and applications of the present disclosure. For example, a system may be battery-operated, or the handle and generator may be integrated. Additionally, a system may include both mechanical and electrical cutting elements. Moreover, certain components are optional, and the disclosure contemplates various configurations and combinations of the elements disclosed herein. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present disclosure as defined by the appended claims.
Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims.
The present application claims priority to U.S. Provisional Ser. No. 63/485,751, filed Feb. 17, 2023, the disclosure of which is hereby incorporated by reference in its entirety as if fully set forth herein.
| Number | Date | Country | |
|---|---|---|---|
| 63485751 | Feb 2023 | US |
