Patent Application
20240041483
The present disclosure generally relates to the field of heart implant devices and implant techniques.
Heart valve dysfunctions, such as valve calcification, can complicate operations to implant medical devices or perform other operations in the heart. Valve stenosis occurs when the heart's valves narrow. This narrowing prevents the valve from opening fully, which reduces or blocks blood flow. When the blood flow through the valve is reduced or blocked, the heart needs to work harder to pump blood. Eventually, this extra work limits the amount of blood it can pump, and this can cause symptoms as well as possibly weaken the heart muscle.
Described herein are one or more methods and/or devices to facilitate implanting of devices through a calcified or otherwise narrowed heart valve, using at least two guidewires.
One general aspect includes a device for advancing a primary guidewire past a heart valve. The device includes a primary guidewire configured to advance past a heart valve. The device also includes a secondary guidewire configured to pull open a leaflet of the heart valve while the primary guidewire advances past the heart valve. The primary guidewire may be independently actuatable from the secondary guidewire. The device can also include a catheter containing both the primary guidewire and the secondary guidewire.
Implementations of the device may include one or more of the following features. The secondary guidewire may include a leaflet anchor configured to removably couple with the leaflet of the heart valve. In an embodiment, the leaflet anchor may include a needle configured to pierce through a proximal surface of the leaflet, and a hook configured to attach to a distal surface of the leaflet, the distal surface opposite the proximal surface.
In one embodiment, the leaflet anchor may include a suction cup configured to couple with a proximal surface of the leaflet. In one embodiment, the leaflet anchor may include a screw. In some embodiments, the leaflet anchor may include a cone shape or pyramid shape having: a pointed end; and a base surface opposite the pointed end; where the pointed end is configured to pierce a proximal surface of the leaflet and the base surface is configured to abut against a distal surface of the leaflet.
In one implementation, the leaflet anchor may include: a first prong actuatable to a first configuration and a second configuration; and a second prong; where in the first configuration, the first prong is substantially parallel to the second prong, and in the second configuration the first prong is substantially perpendicular to the second prong.
The device may include a sheath configured to hold the first prong in the first configuration with the second prong in response to the sheath being in a first position. The sheath may be configured to release the first prong to the second configuration in response to the sheath being in a second position, the second position reached by pulling the sheath away from a distal end of the leaflet anchor. In one embodiment, the first prong is configured to bend towards a right angle in the second configuration.
In one embodiment, the leaflet anchor may include: a first prong actuatable to a first configuration and a second configuration; a second prong; and a joint joining the first prong and the second prong at a point away from distal ends of the first prong and the second prong. In the first configuration, the first prong presses against the second prong, and in the second configuration the first prong is separated from the second prong. In the first configuration, the first prong and the second prong may be configured to hold a portion of the leaflet between them. The device may include a sheath configured to press the first prong against the second prong in the first configuration.
One general aspect includes a method for advancing a primary guidewire past a calcified leaflet. The method may include advancing a catheter configured to surround the primary guidewire and a secondary guidewire. The method can also include attaching a leaflet anchor of the secondary guidewire to the calcified leaflet of a valve. The method can also include retracting the secondary guidewire attached to the calcified leaflet to open the valve. The method may further include advancing the primary guidewire through the open valve.
Implementations of the method may include one or more of the following features. The method may include detaching the secondary guidewire from the calcified leaflet, and utilizing the primary guidewire to perform a medical procedure. For example, the medical procedure can be a transcatheter aortic valve replacement procedure. Retracting the secondary guidewire may include retracting the secondary guidewire through a first lumen of the catheter and advancing the primary guidewire may include advancing the primary guidewire through a second lumen of the catheter.
Another general aspect includes a guidewire configured to removably attach to a leaflet via a leaflet anchor. The guidewire can include a first prong actuatable to a closed configuration and an open configuration. The guidewire can also include a second prong. The guidewire can also include a sheath configured to move from a first position that compresses the first prong against the second prong into the closed configuration, to a second position that releases the first prong from the second prong into the open configuration. In the open configuration, the first prong separates from the second prong and may form a hook, and in the closed configuration, the first prong may form a needle with the second prong.
Implementations of the guidewire may include one or more of the following features. When inserting the leaflet anchor through a proximal surface of a calcified leaflet, the leaflet anchor may be in the closed configuration. When the leaflet anchor hooks to a distal surface of the calcified leaflet, the leaflet anchor may be in the open configuration.
Various embodiments are depicted in the accompanying drawings for illustrative purposes, and should in no way be interpreted as limiting the scope of the inventions. In addition, various features of different disclosed embodiments can be combined to form additional embodiments, which are part of this disclosure. Throughout the drawings, reference numbers may be reused to indicate correspondence between reference elements.
Although certain preferred embodiments and examples are disclosed below, inventive subject matter extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses and to modifications and equivalents thereof. Thus, the scope of the claims that may arise herefrom is not limited by any of the particular embodiments described below. For example, with respect to any method or process disclosed herein, the acts or operations of the method or process may be performed in any suitable sequence and are not necessarily limited to any particular disclosed sequence.
Various operations may be described as multiple discrete operations in turn, in a manner that may be helpful in understanding certain embodiments; however, the order of description should not be construed to imply that these operations are order dependent. Additionally, the structures, systems, and/or apparatuses/devices described herein may be embodied as integrated components or as separate components. For purposes of comparing various embodiments, certain aspects and advantages of these embodiments are described. Furthermore, the headings provided herein are for convenience only and do not necessarily affect the scope or meaning of the claimed invention.
Not necessarily all such aspects or advantages are achieved by any particular embodiment. Thus, for example, various embodiments may be carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other aspects or advantages as may also be taught or suggested herein. Similar reference numbers may be used with respect to separate diagrams and/or embodiments; use of such similar, or identical, reference numbers should not be interpreted as necessarily identifying identical components, and may refer to separate features.
One cause of valve stenosis is the accumulation of deposits of calcium (valve calcification) on the heart valve. Calcium is a mineral found in the blood. As blood repeatedly flows over the valve, deposits of calcium can build up on the valve's cusps. These deposits may never cause any problems. However, in some people, particularly those with a congenitally abnormal valve, calcium deposits result in stiffening of the cusps of the valve. This stiffening narrows the valve. With calcified valves, getting a guidewire past the valve can take considerable time and expertise since the guidewire has to advance, typically against the blood flow, through a small opening due to the calcification.
The following disclosure discuses a dual guidewire system for guiding catheter insertion, where a primary guidewire is configured to guide a catheter to the target site in the heart while a secondary guidewire is configured to anchor itself to a calcified heart valve leaflet and hold open or otherwise enlarge the valve opening for the primary guidewire. The secondary guidewire can include a leaflet anchor for removably attaching to a valve leaflet. In one embodiment, the leaflet anchor includes a sharp needle with a hook, with the needle configured to pierce through a proximal side of the leaflet and the hook configured to attach against the distal side of the leaflet. Other embodiments of the attachment mechanism of the leaflet anchor can include adhesive, pinching arms, suction cups, and/or the like.
In humans and other vertebrate animals, the heart generally comprises a muscular organ having four pumping chambers, wherein the flow thereof is at least partially controlled by various heart valves, namely, the aortic, mitral (or bicuspid), tricuspid, and pulmonary valves. The valves may be configured to open and close in response to a pressure gradient present during various stages of the cardiac cycle (e.g., relaxation and contraction) to at least partially control the flow of blood to a respective region of the heart and/or to blood vessels (e.g., pulmonary, aorta, etc.).
Heart valves may generally comprise a relatively dense fibrous ring, referred to herein as the annulus, as well as a plurality of leaflets or cusps attached to the annulus. Generally, the size and position of the leaflets or cusps may be such that when the heart contracts, the resulting increased blood pressure produced within the corresponding heart chamber forces the leaflets at least partially open to allow flow from the heart chamber. As the pressure in the heart chamber subsides, the pressure in the subsequent chamber or blood vessel may become dominant, and press back against the leaflets. As a result, the leaflets/cusps come in apposition to each other such that the leaflets/cusps coapt, thereby closing the flow passage.
The atrioventricular (i.e., mitral 6 and tricuspid 8) heart valves may further comprise a respective collection of chordae tendineae (16, 11) and papillary muscles (15, 10) for securing the leaflets of the respective valves to promote and/or facilitate proper coaptation of the valve leaflets and prevent prolapse thereof. The papillary muscles (15, 10) may generally comprise finger-like projections from the ventricle wall, while the chordae tendineae (16, 11) may comprise cord-like tendons that connect the papillary muscles to the valve leaflets.
With respect to the mitral valve 6, a normal mitral valve may comprise two leaflets (anterior and posterior) and chordae tendineae 16 connecting the leaflets to two corresponding papillary muscles 15. The papillary muscles 15 originate in the left ventricle wall and project into the left ventricle 3. The valve leaflets of the mitral valve 6 may be prevented from prolapsing into the left atrium 2 by the action of the chordae tendineae 16 tendons connecting the valve leaflets to the papillary muscles 15. The relatively inelastic chordae tendineae 16 are attached at one end to the papillary muscles 15 and at the other to the valve leaflets; chordae tendineae from each of the papillary muscles 15 are attached to a respective leaflet of the mitral valve 6. Thus, when the left ventricle 3 contracts, the intraventricular pressure can force the valve to close, while the chordae tendineae 16 may keep the leaflets coapting together and prevent the valve from opening in the wrong direction, thereby preventing blood to flow back to the left atrium 2. The various cords of the chordae tendineae may have different thicknesses, wherein relatively thinner cords are attached to the free leaflet margin, while relatively thicker cords (e.g., strut cords) are attached farther away from the free margin.
With respect to the tricuspid valve 8, a normal tricuspid valve may comprise three leaflets (two shown in
Heart valve disease represents a condition in which one or more of the valves of the heart fails to function properly. Diseased heart valves may be categorized as stenotic, wherein the valve does not open sufficiently to allow adequate forward flow of blood through the valve, and/or incompetent, wherein the valve does not close completely, causing excessive backward flow of blood through the valve when the valve is in a closed state. In certain conditions, valve disease can be severely debilitating and even fatal if left insufficiently treated. With regard to incompetent heart valves, over time and/or due to various physiological conditions, the position and/or tension of the chordae tendineae and/or papillary muscles may become altered, thereby pulling the valve leaflets at least partly open, which may cause valve regurgitation. For example, functional mitral valve regurgitation can occur when the left ventricle of the heart is distorted or dilated, displacing the papillary muscles, and chordae tendineae attached thereto, that support the mitral valve leaflets. For example, the valve leaflets may no longer come together to close the annulus, thereby resulting in blood flow back into the atrium. If left untreated, functional mitral valve regurgitation can overload the heart and can lead to or accelerate heart failure. Moving or pulling the chordae tendineae closer to the flow axis of the valve annulus according to their natural and healthy positions can potentially reduce occurrence of valve regurgitation.
Some types of valve disease result in leaflet calcification, which can complicate procedures that access the heart through a valve. Mitral annular calcification, characterized by calcium and lipid deposition in the annular fibrosa of the mitral valve, is a degenerative process commonly occurring in the elderly. Patients with mitral annular calcification may also have mitral valve leaflet calcification. In contrast to the mitral valve, calcification involving the tricuspid valve is rare. Isolated cases of tricuspid valve calcification have been reported associated with rheumatic heart disease, bacterial endocarditis, ventricular septal defect, and congenital malformations of the tricuspid valve.
Meanwhile, calcified stenosis of the aortic valve is a well-recognized and relatively common clinical and pathological entity. Aortic valve calcification is a condition in which calcium deposits form on the aortic valve in the heart. These deposits can cause narrowing at the opening of the aortic valve. This narrowing can become severe enough to reduce blood flow through the aortic valve. In contrast, calcific pulmonic stenosis is rarely encountered either at operation or necropsy. Some physicians have observed small deposits of calcium in one or more pulmonic valve cusps in patients who lived into adulthood with left-to right intracardiac shunts, and in older persons with severe pulmonary hypertension secondary to lung disease.
Various solutions disclosed herein relate to devices and methods for accessing the heart through calcified leaflets of a valve using a dual guidewire system. Such devices and methods can be used during procedures including transcatheter aortic valve replacement (TAVR) or transcatheter aortic valve implantation (TAVI). Usually valve replacement requires an open-heart procedure with a “sternotomy,” in which the chest is surgically separated (opened) for the procedure. The TAVR or TAVI procedures can be done through very small openings that leave all the chest bones in place. For example, the TAVR procedure is performed using one of two approaches: entering through the femoral artery (large artery in the groin) using the transfemoral approach, which does not require a surgical incision in the chest; or using a minimally invasive surgical approach with a small incision in the chest and entering through a large artery in the chest or through the tip of the left ventricle (the apex) using a transapical approach.
As referenced above, certain embodiments disclosed herein provide for systems, devices, and methods for advancing a primary guidewire past a calcified leaflet while a secondary guidewire enlarges the valve aperture by pulling on the calcified leaflet. Such devices may be introduced into the patient system through surgical or, advantageously, minimally-invasive means.
A guidewire is a wire or spring typically used as a guide for placement of a larger device or prosthesis, such as a catheter or replacement valve. Guidewires are designed to navigate vessels to reach a target destination. Once the tip of the device arrives at its destination, it acts as a guide that larger catheters can rapidly follow for easier delivery to the treatment site. Guidewires can vary in size, length, stiffness, composition, and shape of the tip.
Generally, guidewires consist of four major components: a core, a wire tip, a body, and a coating. The inner part of the wire is called the core. Typically, the core is either made of very flexible nitinol or stiff stainless steel, which dictates a guidewire's flexibility. The tip refers to the distal end of the wire. Often, the end of the wire tip is wrapped in a ribbon of flexible metal to make the tips more flexible and atraumatic. The body of the wire, surrounding the core, is typically made of coils or polymers. Generally, the body of the wire (e.g., spring coil or polymer cover) is coated by an overlay, a specific material which gives the wire the ability to reduce surface friction, and improve device interaction and guidewire tracking. Depending on the intended use, the coating may be hydrophilic, hydrophobic, or have some other property to aid insertion.
While each of
In one example, the leaflet anchor is a pointed shape with a wider base (e.g., cone, pyramid, etc.) as shown in
As shown in
In an exemplary operation, the needle 425 can pierce through the leaflet 120 from the proximal surface 122 (towards the entry point of the guidewire device 100), creating an entry point through which the hook 420 can pass through the leaflet 120. The hook 420 can then engage with the distal surface 124 (away from the entry point of the guidewire device 100) of the leaflet 120.
Because the suction device 515 attaches to the proximal surface 122, there may be less damage done to the leaflet 120 as piercing through is unnecessary. While some operations may be for implanting an artificial valve, other operations may leave the existing valve in place. In those situations, it may be beneficial to limit damage to the leaflets of the valve to make repair easier. Other embodiments of the dual guidewire device 100 can function similarly by attaching to the proximal surface, but use alternate embodiments of the leaflet anchor, such as screw devices or adhesive to attach to the leaflet 120.
In the first configuration shown in
In the second configuration shown in
In one exemplary use case, after pushing through the secondary guidewire 110 through a valve leaflet while in the first configuration, the user can pull the sheath 610 to the second location 630. The actuatable leaflet anchor 605 then changes from the first configuration to the second configuration. With the biasing prong 615 in the horizontal position, the biasing prong 615 abuts against the distal surface of the leaflet, thereby increasing the surface area against the leaflet. This allows greater force to be applied to the leaflet before the actuatable leaflet anchor 605 damages the leaflet, increasing the chance that the secondary guidewire 110 can pull open the leaflet to a position that enlarges the valve opening to the desired degree.
As discussed above, the actuatable leaflet anchor 605 can be made in a variety of forms, such as a needle, anchor, adhesive, pointed structure with a widened base, or the like. In addition, various types of material can be used for the leaflet anchor and the guidewires, such as nitinol, stainless steel, or other biocompatible material.
While the above has described using the actuatable leaflet anchor 605 to pierce through the leaflet 120 and attach to the distal surface 124 (shown in
In the alternate usage described above, the actuatable leaflet anchor 605 may be adapted to better pinch the leaflet. For example, the first prong 615 and second prong 620 may have wider, flatter ends, to increase the contact surface area that pinches the leaflet tissue. In another example, the first prong 615 and second prong 620 may be attached together by a joint below the ends of the prongs, similar to pliers and scissors, to better facilitate the pinching motion by the two prongs. A spring or other biasing material may be located near the joint in order to push open the two prongs, unless held together by the sheath 610. In that implementation, the sheath 610 can be used to close the prongs together by advancing distally and release the prongs by retreating proximally.
At block 705, the health provider gains access to the femoral artery from an insertion site on the patient's body. The health provider can insert a catheter at the insertion site and into the femoral artery. In some embodiments, the catheter may have separate lumens for the primary guidewire 105 and the secondary guidewire 110. Other embodiments may use a single lumen, with the guidewires sharing the lumen. In some embodiments, more than two guidewires may be used, with separate lumens for each guidewire.
At block 710, the health provider inserts the dual guidewire device 100 into the aorta and aortic arch, to approach the aortic valve. In some embodiments, one or more guidewires may already be in the catheter while the catheter is inserted into the patient's body. In other embodiments, the catheter is empty, with the guidewires inserted after the catheter reaches the target site (e.g., aortic valve) in the body.
At block 715, the health provider attaches the secondary guidewire to a leaflet of the aortic valve. As discussed above, various types of leaflet anchors can be used, from mechanical to adhesive, to attach to a calcified leaflet.
In some embodiments, the secondary guidewire may be attached to the proximal surface of the leaflet. For example, the secondary guidewire may use a suction cup or adhesive to attach to the surface. In one embodiment, the leaflet anchor is a screw that is screwed into the leaflet, for example, by rotating the guidewire to drive the screw into the leaflet tissue. In another embodiment, the leaflet anchor includes a pair of jaws or prongs that pivot on a joint, similar to pliers, that pinch the leaflet between the jaws or prongs.
In other embodiments, the secondary guidewire may pierce through the leaflet and press against the distal surface of the leaflet. For example, the leaflet anchor can be a needle and hook structure, a tapered cone or pyramid structure, or some of the embodiments described in the earlier figures.
At block 720, the health provider pulls back the leaflet with the secondary guidewire to open the aortic valve. In some embodiments, the dual guidewire device may have a winch, reel, or other mechanism to pull the guidewire attached to the end of the guidewire, outside the patient's body. In some embodiments, the health provider may manually pull on the secondary guidewire.
At block 725, the secondary guidewire pulls the calcified leaflet and widens the valve opening, allowing the primary guidewire to be pushed through the enlarged opening. In some embodiments, multiple guidewires may be used to attached to multiple leaflets. For example, if a single guidewire pulling on a single leaflet does sufficiently enlarge the opening, a second guidewire can be attached to a second leaflet to further open the valve. Even a third guidewire can be used to attached to a third leaflet (e.g., when opening a tricuspid valve).
At block 730, the secondary guidewire can be detached from the leaflet. For example, for leaflet anchors that pierce through the leaflet and abut against the distal surface of the leaflet, a covering sheath may be moved over the leaflet anchor, allowing the leaflet anchor to be pulled back through the leaflet. For leaflet anchors that attach to the proximal surface of the leaflet, various detachment methods can be used to detach the leaflet anchor. For example, a screw anchor can be unscrewed, a jaw anchor can be opened to release the leaflet, and a suction cup can be lifted to release a vacuum seal. In some embodiments, an adhesive anchor may use an adhesive that is formulated to dissolve after a certain amount of time, thereby releasing the leaflet. Once detached, the secondary guidewire can be pulled out of the catheter and out of the patient's body.
At block 735, the primary guidewire can then be guided to its destination in the heart, where it can be used in performing various possible medical procedures, such as a TAVR procedure or other procedure for implanting a device or operating on the heart.
Depending on the embodiment, certain acts, events, or functions of any of the processes described herein can be performed in a different sequence, may be added, merged, or left out altogether. Thus, in certain embodiments, not all described acts or events are necessary for the practice of the processes. Moreover, in certain embodiments, acts or events may be performed concurrently, rather than sequentially.
Conditional language used herein, such as, among others, “can,” “could,” “might,” “may,” “e.g.,” and the like, unless specifically stated otherwise, or otherwise understood within the context as used, is intended in its ordinary sense and is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements and/or steps. Thus, such conditional language is not generally intended to imply that features, elements and/or steps are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without author input or prompting, whether these features, elements and/or steps are included or are to be performed in any particular embodiment. The terms “comprising,” “including,” “having,” and the like are synonymous, are used in their ordinary sense, and are used inclusively, in an open-ended fashion, and do not exclude additional elements, features, acts, operations, and so forth. Also, the term “or” is used in its inclusive sense (and not in its exclusive sense) so that when used, for example, to connect a list of elements, the term “or” means one, some, or all of the elements in the list. Conjunctive language such as the phrase “at least one of X, Y and Z,” unless specifically stated otherwise, is understood with the context as used in general to convey that an item, term, element, etc. may be either X, Y or Z. Thus, such conjunctive language is not generally intended to imply that certain embodiments require at least one of X, at least one of Y and at least one of Z to each be present.
It should be understood that certain ordinal terms (e.g., “first” or “second”, “primary” or “secondary”) may be provided for ease of reference and do not necessarily imply physical characteristics or ordering. Therefore, as used herein, an ordinal term (e.g., “first,” “second,” “third,” etc.) used to modify an element, such as a structure, a component, an operation, etc., does not necessarily indicate priority or order of the element with respect to any other element, but rather may generally distinguish the element from another element having a similar or identical name (but for use of the ordinal term). In addition, as used herein, indefinite articles (“a” and “an”) may indicate “one or more” rather than “one.” Further, an operation performed “based on” a condition or event may also be performed based on one or more other conditions or events not explicitly recited.
Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which example embodiments belong. It be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
The spatially relative terms “outer,” “inner,” “upper,” “lower,” “below,” “above,” “vertical,” “horizontal,” “proximal,” “distal,” and similar terms, may be used herein for ease of description to describe the relations between one element or component and another element or component as illustrated in the drawings. It be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation, in addition to the orientation depicted in the drawings. For example, in the case where a device shown in the drawing is turned over, the device positioned “below” or “beneath” another device may be placed “above” another device. Accordingly, the illustrative term “below” may include both the lower and upper positions. The device may also be oriented in the other direction, and thus the spatially relative terms may be interpreted differently depending on the orientations.
Unless otherwise expressly stated, comparative and/or quantitative terms, such as “less,” “more,” “greater,” and the like, are intended to encompass the concepts of equality. For example, “less” can mean not only “less” in the strictest mathematical sense, but also, “less than or equal to.”
It should be appreciated that in the above description of embodiments, various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that any claim require more features than are expressly recited in that claim. Moreover, any components, features, or steps illustrated and/or described in a particular embodiment herein can be applied to or used with any other embodiment(s). Further, no component, feature, step, or group of components, features, or steps are necessary or indispensable for each embodiment. Thus, it is intended that the scope of the inventions herein disclosed and claimed below should not be limited by the particular embodiments described above, but should be determined only by a fair reading of the claims that follow.
This application is a continuation of International Patent Application No. PCT/US2022/019188, filed on Mar. 7, 2022, and entitled DUAL GUIDEWIRE SYSTEM FOR CALCIFIED VALVES, which claims priority to U.S. Provisional Application No. 63/164,438, filed on Mar. 22, 2021, entitled DUAL GUIDEWIRE SYSTEM FOR CALCIFIED VALVES, the disclosures of which are hereby incorporated by reference in their entireties.
| Number | Date | Country | |
|---|---|---|---|
| 63164438 | Mar 2021 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/US2022/019188 | Mar 2022 | US |
| Child | 18367021 | US |
