The present disclosure relates generally to devices and methods for anchoring systems such as an atrioventricular regurgitation prevention system in a ventricle.
Heart valve disease, such as valve regurgitation, is typically treated by replacing or repairing the diseased valve during open-heart surgery. However, open-heart surgery is highly invasive and is therefore not an option for many patients. For high-risk patients, a less-invasive method for repair of heart valves is considered generally advantageous. In patients with severe/torrential tricuspid valve regurgitation, the tricuspid valve annulus and the right ventricle are often seen to have dilated abnormally large amounts, often times resulting in a severe loss of tricuspid valve leaflet coaptation.
One solution is seen in the FORMA Transcatheter Tricuspid Repair System from Edwards Lifesciences, Inc. of Irvine, CA, as well as solutions disclosed in U.S. Pat. No. 9,474,605, both expressly incorporated herein, which introduce a gap-filling element into the tricuspid valve that restores leaflet coaptation, reduces tricuspid regurgitation (TR) and right atrium (RA) pressure, and thereby alleviates classic TR patient symptoms and improves quality of life. A flexible rail having a ventricular anchor on the distal end thereof adapted to anchor into tissue within a ventricle is first deployed percutaneously. A repair catheter passes along the flexible rail, and a leaflet coaptation member or spacer on a distal end of the catheter is located within the native valve leaflets. When in place, the spacer fills gaps between the tricuspid leaflets and reduces or eliminates regurgitation through the native valve. Various alternative anchoring techniques include deployment of the anchor trans-pericardial (through the base of the RV and through the pericardium) and trans-septal (through the interventricular septum from the RV through to the LV). Both U.S. Pat. No. 9,474,605 and WO2020197854A1 document alternative anchoring techniques and are expressly incorporated herein.
Despite these and other cardiac implants anchored in subvalvular spaces, the task of securely anchoring in the ventricles, especially while the heart is beating, remains difficult and requires improvements.
The present invention relates generally to devices and methods for securely placing an anchor in the ventricles for a cardiac implant system.
One embodiment disclosed herein is an active puncturing tool in the form of a modified needle apparatus that incorporates EKG-based myocardial puncture sensing to guide in-vivo myocardial puncture in two modes—from the ventricle to the exterior of the heart, and between the ventricles across the septal wall. The modified needle apparatus and delivery system incorporates standard, off-the-shelf 5-lead EKG terminals and monitors (available readily at all hospitals) to add an additional real-time indication of needle tip location within the heart. Used in tandem with fluoroscopy and echocardiography (contrast/agitated saline injections), this dramatically reduces the ambiguity with respect to needle tip visualization, reduces procedure times and reduces intra-procedural complications associated with myocardial puncture.
For trans-pericardial anchoring, the modified needle apparatus and attendant methodology is used to determine what the needle tip is in contact with, specifically for the purpose of bringing the needle tip from the right ventricle out of the heart and into the space between the pericardium and the chest wall. The location of the needle tip is determined as it advances through various zones from observing the EKG trace: namely, in ventricular free space/blood, in contact with the inner wall of the base of the right ventricle, partially through the right ventricular myocardium (lodged inside the myocardium), through the myocardium and in the pericardial space, fully through the pericardium and into the space between the pericardium and the inner chest wall. The EKG traces associated with each of these spaces are logged and each are seen to have distinct traces that can be used to guide RV myocardial puncture.
Alternatively, for trans-septal puncturing and anchoring, the modified needle apparatus and methodology is used to determine primarily when the needle tip crosses over from the RV into the LV. Discrete EKG signals noted here are found when the location of the needle tip advances through various zones as follows: in right ventricular free space/blood, in contact with the inter-ventricular septum myocardium, partially through or wedged inside the inter-ventricular septum myocardium, completely through the inter-ventricular septum and in LV free space, and when advanced too far to be in contact with the LV free wall.
The present application discloses a system for delivering and deploying cardiac anchors, comprising an active puncturing tool. The tool includes a proximal control handle with a flexible sheath extending distally therefrom. A flexible puncturing needle extends through the sheath and is linearly movable therein to a position beyond a distal tip of the sheath, the needle being electrically insulated except at a sharp distal tip. A cardiac anchor is movable through the sheath and relative to the needle to a position beyond the sharp distal tip. Finally, an EKG system is connected to the tool so that one lead is in electrical contact with a proximal end of the needle.
The cardiac anchor delivery and deployment system may further comprise a regurgitation reduction spacer sized to fit within leaflets of an atrioventricular valve and configured to coapt against the leaflets to reduce regurgitation therebetween. The spacer preferably has a length such that the proximal end resides within the atrium and the distal end resides within the ventricle. A flexible tether connects the spacer to the cardiac anchor. In one form, the cardiac anchor is an expandable disk-shaped anchor configured to abut cardiac tissue. In another form, the cardiac anchor is a tissue anchor configured to embed in cardiac tissue.
On tissue anchor configured to embed in cardiac tissue comprises:
In the systems described above, the control handle may have a first slider movable thereon configured to axially displace the needle relative to the sheath, and a second slider movable thereon configured to axially displace the cardiac anchor relative to the needle. The system first and second sliders may be coupled for common movement, and further including a lock which may be released to permit the second slider to move with respect to the first slider. Each of the first and second sliders may have an outer finger tab labeled with an indicator of the respective function of each. The control handle may further include an actuator for angling a tip of the sheath.
In one embodiment, the needle is hollow and the cardiac anchor is positioned within and deployable from within the needle. The control handle may further include a plurality of fluid ports connected thereto for introducing or withdrawing fluid or gas from concentric spaces within the system, including a space between the sheath and needle, and a space between the needle and cardiac anchor. The EKG may be a 5-lead EKG.
Another aspect described herein is a tissue anchor for medically implanted systems, comprising a tubular barrel defining a longitudinal axis having a plurality of distally-extending tines configured to be embedded into tissue, the tines being biased toward a relaxed configuration where the tines splay radially outward from the axis. A flexible proximal shaft connects to the barrel, and a plurality of sutures are each connected to one of the tines and extend proximally through the shaft. Each suture extends outward from the barrel and along a respective tine to be fastened at a distal tip thereof, wherein tension on the sutures helps prevent the tines from bending toward the axis upon application of proximal forces on the anchor tending to pull the anchor from within tissue. Each of the tines may be formed as a laser-cut portion of a tube that also forms the tubular barrel, and each tine has a plurality of cleats along its length through which the sutures pass before reaching the distal tip.
The present application discloses a method for delivering and deploying a cardiac anchor into a patient. The method comprises first providing an active puncturing tool having a proximal control handle with a flexible sheath extending distally therefrom. A flexible puncturing needle extends through the sheath and is linearly movable therein to a position beyond a distal tip of the sheath, the needle being electrically insulated except at a sharp distal tip. A cardiac anchor is movable through the sheath and relative to the needle to a position beyond the sharp distal tip. Also provided is an EKG system, the method involving connecting the EKG system to the patient and connecting one lead to a proximal end of the needle. The sheath is advanced through the vasculature until the distal tip thereof is in proximity to a tissue surface within the heart. The needle is then advanced from the distal tip of the sheath while monitoring a location of the sharp distal tip of the needle on a monitor of the EKG system. Advancement of the needle is halted at a desired location, and the cardiac anchor advanced from within the needle to deploy the cardiac anchor at the desired location.
The method may also include deploying a regurgitation reduction spacer within leaflets of an atrioventricular valve configured to coapt against the leaflets to reduce regurgitation therebetween. Desirably, the spacer has a length such that the proximal end resides within the atrium and the distal end resides within the ventricle.
One such method of deploying a regurgitation reduction spacer includes advancing the sheath until the distal tip thereof is in a cavity of the ventricle in proximity to an inner surface thereof, advancing the needle through cardiac tissue to a bodily space, advancing the cardiac anchor from within the needle, the cardiac anchor being self-expandable to provide an external anchor, withdrawing the needle and sheath, and connecting a flexible tether between the cardiac anchor and the spacer. The cardiac anchor may be an expandable disk-shaped anchor, and the cardiac tissue may be myocardium with the desired location being outside of the heart, for instance outside of the pericardial sac. The ventricle may be a first ventricle, and the cardiac tissue is septal tissue between the first ventricle and a second ventricle, and the desired location is in the second ventricle.
A second such method of deploying a regurgitation reduction spacer includes advancing the sheath until the distal tip thereof is in a cavity of a ventricle in proximity to an inner surface thereof, advancing the needle into cardiac tissue, advancing the cardiac anchor from within the needle, the cardiac anchor being self-expandable to provide an internal tissue anchor embedded in cardiac tissue, withdrawing the needle and sheath, and connecting a flexible tether between the cardiac anchor and the spacer.
In any of the methods described above, the EKG is a 5-lead EKG and the method includes applying 4 of the leads to the chest of the patient. The methods may further include, while advancing the needle, simultaneously monitoring the location of the sharp distal tip of the needle with at least one of fluoroscopy and echocardiography. Similarly, the methods may also include, while advancing the needle, simultaneously monitoring the location of the sharp distal tip of the needle with fluoroscopy and injecting contrast medium into an access tube in the handle which is in fluid communication with an opening at the sharp distal tip of the needle.
A further understanding of the nature and advantages of the present invention are set forth in the following description and claims, particularly when considered in conjunction with the accompanying drawings in which like parts bear like reference numerals.
To further clarify various aspects of embodiments of the present disclosure, a more particular description of the certain embodiments will be made by reference to various aspects of the appended drawings. It is appreciated that these drawings depict only typical embodiments of the present disclosure and are therefore not to be considered limiting of the scope of the disclosure. Moreover, while the figures may be drawn to scale for some embodiments, the figures are not necessarily drawn to scale for all embodiments. Embodiments of the present disclosure will be described and explained with additional specificity and detail using the accompanying drawings.
The following description refers to the accompanying drawings, which illustrate specific embodiments. Other embodiments having different structures and operation do not depart from the scope of the present disclosure.
The present application discloses systems and methods for anchoring cardiac implants, in particular as illustrated a heart valve regurgitation reduction spacer within a heart valve. Such heart valve regurgitation reduction systems may be implanted within the left or right side of the heart and may extend out of the heart into the vasculature, for example, to the subclavian vein. However, the principles disclosed herein for anchoring such an implanted device are suitable for other applications as well.
A distal device anchor 26 secures a distal end of the rail 22 at the apex of the right ventricle RV, or to other anatomical features within the ventricle. The anchor rail 22 may be constructed as a braided wire rod, or cable, and is desirably hollow to enable passage over a guide wire (not shown). Further details of the anchor rail 22 and device anchor 26 are seen in U.S. Pat. No. 9,474,605 to Rowe, et al.
The repair catheter shaft 24 carries a coapting element or spacer 30 on its distal end portion that is ultimately positioned within the tricuspid valve TV, the leaflets of which are shown closed in systole and in contact with the spacer 30. A variety of coapting elements may be utilized, the common feature of which is the goal of providing a plug of sorts within the heart valve leaflets to mitigate or otherwise eliminate regurgitation. In the illustrated embodiment, the spacer 30 includes an expandable body formed of a latticework of struts arranged to be auxetic, or have a negative Poisson's ratio, that may be adjusted in vivo, such as disclosed in U.S. Patent Publication No. 2019/0358029, while other coapting elements are disclosed in U.S. Pat. Nos. 9,474,605 and 9,636,223, the entire disclosures which are expressly incorporated herein by reference. The spacer 30 is delivered in a radially contracted state to reduce the size of the incision used and facilitate passage through the vasculature and is then expanded within the valve leaflets.
A locking mechanism is provided on the regurgitation repair catheter 20 to lock the axial position of the spacer 30 within the tricuspid valve TV and relative to the fixed anchor rail 22. For example, a locking collet 32 along the length of the repair catheter shaft 24 permits the physician to selectively lock the position of the shaft, and thus the connected spacer 30, along the anchor rail 22. There are of course a number of ways to lock a catheter over a concentric guide rail, and the application should not be considered limited to the illustrated embodiment. For instance, rather than a locking collet 32, a crimpable section such as a stainless-steel tube may be included on the repair catheter shaft 24 at a location near the skin entry point and spaced apart from the location of the spacer 30. The physician need only position the spacer 30 within the leaflets, crimp the catheter shaft 24 onto the anchor rail 22, and then sever both the catheter and rail above or proximal to the crimp point.
A proximal length of the repair catheter 20 including the locking collet 32 exits the subclavian vein SV through a sealed puncture and remains implanted subcutaneously; preferably coiling upon itself as shown. In the procedure, the physician first ensures proper positioning of the spacer 30 within the tricuspid valve TV, locks the repair catheter 20 with respect to the anchor rail 22 by actuating the locking collet 32, or by another means, and then severs that portion of the repair catheter shaft 24 that extends proximally from the locking collet. The collet 32 and/or coiled portion of the repair catheter shaft 24 may be sutured or otherwise anchored in place to subcutaneous tissues outside the subclavian vein SV. It is also worth noting that because the repair catheter 20 initially slides with respect to the anchor rail 22, it may be completely removed to withdraw the spacer 30 and abort the procedure during implantation. The implant configuration is like that practiced when securing a pacemaker with an electrode in the right atrium muscle tissue and the leads extending to the associated pulse generator placed outside the subclavian vein. Indeed, the current procedure may be performed in conjunction with the implant of a pacing lead.
The anchor 56 could alternatively be placed across the intraventricular septum or septal wall SW, as in
As seen in
In this trans-pericardial procedure, as will be described in more detail below, the active puncturing tool 70 indicates when the needle tip is still inside the catheter, in contact with the myocardium, within the myocardium, completely through the myocardium and within the space inside the pericardial sac 76, in contact with the pericardium, and through the pericardium. Each of these positions of the needle have an easily identifiable EKG trace.
The tissue anchor 56 is thus delivered to a deployment site in a linear configuration within the tool 70, and then expelled from the distal opening 74 as seen in
Visualization of the location of the puncturing needle 72 while passing through the myocardium and pericardium is challenging solely using fluoroscopy or echocardiography (ultrasound) techniques. Most cath-labs and hybrid operating rooms are equipped with fluoroscopy as well as multi-modal echocardiographic technology, as available imaging modalities which are widely used for many different medical device procedures. Fluoroscopy to visualize contrast bolus injections down the length of the needle and evaluate needle tip location is helpful but provides only an approximate location and is easy to be fooled into a false plane of attack due to a bad fluoroscopy angle. Also, depending on the patient, image quality is not always crisp and contrast bolus injections can often pool in one position or wash away too quickly. Echocardiography is hindered primarily due to the depth of the needle within the heart. Both the trans-pericardial and trans-septal approaches perform punctures deep in the RV, making it difficult for both Transesophageal Echocardiogram (TEE) and Intracardiac ECHO (ICE) to have the relevant resolution needed to fully confirm catheter tip location quickly.
Supplementing one or both of fluoroscopy and echocardiography with the currently disclosed active puncturing tool 70 provides a non-visual confirmation that the needle tip is in contact with the proper location and a secondary real-time indication of what the needle is in contact with. The active puncturing tool 70 is desirably not a replacement for any of these imaging modalities, it is meant to augment and be used in tandem with them for best results with respect to navigating, imaging and controlling myocardial puncture both trans-pericardial and trans-septal passages (and perhaps also for punctures in other places in the heart).
For the trans-pericardial anchoring approach shown above in
The needle apparatus described herein also provides advantages for securing the trans-septal anchor as shown in
A typical 5-lead EKG setup includes one lead for each of the limbs (2 arms and 2 legs means 4 leads total on the patient) placed on the chest, roughly as seen in
In the approach technique shown, an elongated flexible sheath 82 of the active needle tool 70 is advanced from the groin area upward through the femoral vein into the right atrium, as will be shown. Techniques for incising the patient and introducing the sheath 82 into the femoral vein are well known, as are flexible sheaths and needles 72 of sufficient length to reach the heart from the groin area. The sheath 82 may be formed of a suitable flexible polymer, while the flexible puncturing needle 72 may be polymeric or Nitinol. The specifics will not be further detailed. Of course, this schematic illustration is but one possible access pathway. Likewise, alternatives pathways to access the right atrium include downward from the neck through the internal jugular vein or subclavian vein, and the present application should not be considered limited to any particular access pathway.
The active puncturing tool 70 generally comprises a proximal control handle 84 from which the flexible sheath 82 extends distally. The rear end of the puncturing needle 72 is seen projecting from a rear end of the control handle 84. The needle 72 is shown extending a greater distance than would be normal for the purpose of illustration. The needle 72 is hollow and extends along the length of the flexible sheath 82 from a location near the distal end thereof and proximally through the control handle 84.
The control handle 84 has a sleeve 86 and rotation ring 88 toward its distal end which actuate a steering mechanism for bending the flexible sheath 82. Although it will not be described in great detail, the sleeve 86 rotates about a longitudinal axis of the tool 70 and has an elongated slot 87 into which fits a similarly sized rail 89. The rail 89 is coupled to a rotation mechanism configured to displace a pull wire (not shown) extending down the length and to the end of the flexible sheath 82. By fastening the pull wire to one side of the distal tip of the flexible sheath 82, the distal tip may be deflected toward that side.
A gripping portion of the control handle 84 houses a pair of sliders 90, 92 which linearly displace, respectively, the puncturing needle 72 and the expandable anchor 56 through the needle. As will be described below, the two sliders 90, 92 are coupled to move axially together within a hollow housing of the control handle 84. Additionally, the proximal slider 92 is adapted to move axially relative to the distal slider 90 upon actuation of a locking tab 94. In particular, the hollow needle 72 extends to the end of the flexible sheath 82 and the distal slider 90 engages the needle for axial movement. The proximal slider 92 engages a pusher for the expandable anchor 56 so that the anchor may be displaced through the hollow needle 72. Concentric spaces are thus formed between the several concentrically-arranged tubes extending along the sheath 82.
A distal fluid port 96, and a pair of proximal fluid ports 98a, 98b are connected to different chambers within handle 84 for aspiration or injecting contrast medium. For example, one of the proximal fluid ports 98a, 98b may be used to inject contrast medium into the needle 72 so that it may be seen on fluoroscope in conjunction with the EKG locating method. Alternatively, each of the fluid ports 96, 98a, 98b may be used to withdrawing fluid or gas from concentric spaces within the system, including a space between the sheath 82 and needle 72, and a space between the needle 72 and cardiac anchor 56.
It should again be noted that the puncturing needle 72 is configured as an electrode to transmit electrical cardiac pulses from within the body to an EKG monitor.
The puncturing needle 72 is but one of a number of potential probes or locating tips that may be utilized in the practice of the present locating and deploying system and method. The hollow needle 72 is particularly useful as the anchor 56 may then be deployed directly from its distal tip 110. However, a solid probe may also be used which then acts as a guidewire of sorts for delivery of an anchor over it, such as described below with respect to the embodiment shown in
Further, the flexible electrode probe or electrode needle is made to conduct electrical pulses from within the heart, in or out of tissue. Such pulses are typically measured in voltage changes, and thus the probe or needle is made of an electrically conductive material such as copper or a ferromagnetic alloy. In one embodiment, the probe or needle is formed of conductive Stainless Steel, such as 304 SS alloy with 8% chromium and 8% nickel.
Subsequently, further advancement of the distal tip 110 through the myocardium and into the space within the pericardial sac as seen in
Finally,
In combination with one or both of fluoroscopy and echo, utilization of the active puncturing tool 70 greatly enhances the ability to quickly and accurately locate the distal tip 110 of the needle 72 for subsequent deployment of the anchor 56. With this additional indication, it becomes readily apparent in the trans-pericardial approach, when the needle 72 has transitioned from the RV space through to the pericardial space and further through to the chest cavity. During each of these steps, the operator will have a live real-time readout on the EKG monitor with a signal trace that is specific to what the needle 72 is in direct contact with. For example, as mentioned, transitioning from the RV free space to contact with the RV myocardium results in a significant S-T segment elevation in the EKG, indicating with great confidence that the needle tip is in contact with the myocardium. Once the needle is pushed through to the free space of the chest cavity, this S-T segment elevation disappears, and the operator can confirm they are in a free space to deploy the anchor. Incorporating this additional sensor input has reduced the time required to confirm successful puncture and dramatically reduced intra-procedural complications during animal studies that have been conducted.
A plurality of retention sutures or filaments 128 extend through the tether 126 and proximally to the control handle 84. Each of the retention sutures 128 emerges radially outward through one of a plurality of holes 130 in the tubular barrel 122 and extends along primarily on the outside of one of the tines 124 to be secured at a distal tip thereof. In one embodiment, a series of cleats 132 are formed along each tine 24 and the retention suture 128 is woven through the cleats. For example, each of the cleats 132 may be formed by a pair of openings separated by a bridge such that the suture 128 passes down and then back up again through the thickness of each tine. The sutures 128 extend along radially outer sides of the tines 124 so as to exert an outward force thereon when pulled.
The anchor 120 is shown with three tines 124 evenly distributed about a longitudinal axis of the tubular barrel 122 (i.e., 120° apart) which are relatively wider than thick and have rounded distal tips. Of course, there may be more than three tines 124 and the distal tips may be more pointed. The tines 124 may be formed from an extension of the tubular barrel 122 and thus have convex outer surfaces, though they also may be flattened. Preferably, the anchor 120 is formed by laser cutting a tubular blank of Nitinol, and shape set (i.e., heat treated) so that the tines 124 splay outward when relaxed. The tines 124 thus having an undeployed configuration in which they are constrained substantially longitudinally within the needle 72, extending in a distal direction, and a deployed configuration wherein the tines are advanced distally from within the needle 72 and splay radially outward. The tines 124 each have a radially outward spring bias so as to separate in the deployed configuration toward a relaxed configuration with their free ends extending generally in a proximal direction.
The retention sutures 128 are utilized to apply tensile force along and to the distal tip of each of the tines 124. With reference to the sectional view of
Subsequently, as shown in
As mentioned, the needle location system and method are useful for a number of different cardiac procedures. For example,
While the foregoing is a complete description of the preferred embodiments of the invention, various alternatives, modifications, and equivalents may be used. Moreover, it will be obvious that certain other modifications may be practiced within the scope of the appended claims.
This application is a continuation of International Patent Application No. PCT/US2021/064832, filed Dec. 22, 2021, and titled “Cardiac Anchoring Solutions”, which published as WO 2022/164557, and which claims priority to and the benefit of U.S. Provisional Patent Application No. 63/144,281, filed Feb. 1, 2021, and titled “Cardiac Anchoring Solutions”, the entire disclosures all of which are incorporated by reference for all purposes.
Number | Date | Country | |
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63144281 | Feb 2021 | US |
Number | Date | Country | |
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Parent | PCT/US2021/064832 | Dec 2021 | US |
Child | 18361637 | US |