FIELD OF THE INVENTION

Some applications of the present invention relate in general to valve replacement. More specifically, some applications of the present invention relate to prosthetic valves for replacement of a cardiac valve.

BACKGROUND

Ischemic heart disease causes regurgitation of a heart valve by the combination of ischemic dysfunction of the papillary muscles, and the dilatation of the ventricle that is present in ischemic heart disease, with the subsequent displacement of the papillary muscles and the dilatation of the valve annulus.

Dilation of the annulus of the valve prevents the valve leaflets from fully coapting when the valve is closed. Regurgitation of blood from the ventricle into the atrium results in increased total stroke volume and decreased cardiac output, and ultimate weakening of the ventricle secondary to a volume overload and a pressure overload of the atrium.

SUMMARY OF THE INVENTION

For some applications of the invention, a prosthetic valve support is provided for facilitating minimally invasive (e.g., transcatheter and/or transluminal) implantation of a prosthetic valve at a native valve of a subject. The native valve typically has native check valve functionality, i.e., it functions as a check valve. It is understood that a diseased valve has sub-optimal native check valve functionality, however the term “check valve functionality,” as used in the context of the specification and in the claims, when used with respect to a native valve, refers to the native level of check valve functionality of the native valve. The prosthetic valve support is typically couplable to the native valve (e.g., to leaflets thereof) of the subject without eliminating the check valve functionality of the native valve. The prosthetic valve is subsequently implanted at the native valve by coupling the prosthetic valve to the prosthetic valve support, typically by expanding the prosthetic valve within one or more openings defined by the prosthetic valve support. The implantation of the prosthetic valve at the native valve replaces, at least in part, the check valve functionality of the native valve with substitute check valve functionality of the prosthetic valve. The prosthetic valve support comprises tissue-engaging elements, such as clips. Typically, but not necessarily, the prosthetic valve support further comprises (1) an upstream support portion, configured to be placed against an upstream surface of the native valve, and shaped to define one of the openings, and (2) a stabilizing element, shaped to define another of the openings.

For some applications, the prosthetic valve support is configured to be coupled to the native valve (e.g., to leaflets thereof) without eliminating the check valve functionality of the native valve, by allowing (1) the native leaflets to define a single orifice, and (2) the native valve to function as a single check valve (e.g., to function in a manner that is generally similar to the natural (e.g., physiological) function of the native valve). For some applications, the prosthetic valve support is configured to be coupled to the native valve (e.g., to leaflets thereof) without eliminating the check valve functionality by coupling together respective portions of two leaflets, such that (1) the native leaflets define two orifices, and (2) the native valve functions as two (e.g., parallel) check valves.

For some applications, it is hypothesized that the use of a two-component implant (i.e., comprising the prosthetic valve support and a separate prosthetic valve), advantageously facilitates delivery of the prosthetic valve via a catheter narrower than 28 Fr (e.g., by allowing the use of a ‘minimalistic’ prosthetic valve, such as a prosthetic valve with few or no appendages).

For some applications, it is hypothesized that the use of a prosthetic valve support that does not eliminate check valve functionality of the native valve, facilitates the separate delivery of the prosthetic valve support and the prosthetic valve (i.e., a two-stage delivery), and thereby further facilitates the use of a narrow catheter.

For some applications, it is further hypothesized that the use of the prosthetic valve support enhances the check valve functionality of the native valve, and thereby provides both (1) “repair” of the native valve, and (2) an implantation site that is pre-prepared for subsequent implantation of a prosthetic valve at a later date, should such implantation be subsequently considered necessary.

There is therefore provided, in accordance with an application of the present invention, apparatus for use with a prosthetic valve for implantation at a native valve of a subject, the native valve including at least one native leaflet, the apparatus including:

a prosthetic valve support, including:an upstream support portion, being configured to be placed against an upstream side of the native valve, and having an inner perimeter that defines an opening that is configured to receive the prosthetic valve, andat least one clip:including at least two clip arms and a clip-controller interface, the clip-controller interface being coupled to at least one of the clip arms, andbeing configured to be coupled to a native leaflet of the native valve; and at least one clip controller, reversibly couplable to the clip-controller interface, and configured to facilitate opening and closing of the clip.

In an application, the at least two clip arms include a first clip arm, configured to be disposed against an upstream surface of the leaflet, and a second clip arm, configured to be disposed against a downstream surface of the leaflet.

In an application, the clip controller is configured to facilitate opening and closing of the clip irrespective of a state of expansion of the prosthetic valve support.

In an application, the at least one clip includes at least a first clip and a second clip, and the second clip is openable and closeable independently of the first clip.

In an application, the at least one clip includes at least a first clip and a second clip, and the first clip is fixedly coupled to the second clip, and is configured to be decoupled from the second clip.

In an application, the at least one clip is configured to be coupled to a single native leaflet of the native valve.

In an application, the at least one clip is configured to be lockable such that the first clip arm is locked with respect to the second clip arm.

In an application:

the native valve includes at least a first native leaflet and a second native leaflet,

the at least one clip includes at least a first clip and a second clip, the first clip being configured to be coupled to the first leaflet, and the second clip being configured to be coupled to the second leaflet, and

the prosthetic valve support is configured such that, when (1) the upstream support portion is disposed against the upstream side of the native valve, (2) the first clip is coupled to the first leaflet, and (3) the second clip is coupled to the second leaflet, the first clip moves toward the second clip during ventricular systole of the subject, and moves away from the second clip during ventricular diastole of the subject.

In an application, the clip is flexibly coupled to the upstream support portion.

In an application, the clip is coupled to the upstream support portion via a flexible connector, the flexible connector having a length from the upstream support portion to the clip, and the length of the flexible connector is variable.

In an application, the upstream support portion is generally flat.

In an application, the inner perimeter defines the opening, such that the opening has a depth and a width, and the width of the opening is more than four times greater than the depth of the opening.

In an application, the upstream support portion has a free inner edge, and the free inner edge defines the inner perimeter.

In an application, the inner perimeter defines an opening that has a diameter, and the upstream support portion has a diameter that is at least 10 percent greater than the diameter of the opening.

In an application, no part of the prosthetic valve support that circumscribes a space that has a perimeter greater than 60 mm has a height of more than 20 mm.

There is further provided, in accordance with an application of the present invention, apparatus for facilitating implantation of a prosthetic valve at a native heart valve of a subject, the native heart valve including a native annulus and a plurality of native leaflets that provide check valve functionality, the apparatus including a prosthetic valve support, the prosthetic valve support:

being configured to be transluminally-delivered to the native valve and to be deployed at the native valve, and including one or more tissue-engaging elements, configured to couple the prosthetic valve support to the native leaflets without eliminating the check valve functionality.

In an application, the tissue-engaging elements are configured to couple the prosthetic valve support to the native leaflets without eliminating the check valve functionality, by coupling the prosthetic valve support to the native leaflets such that:

the native leaflets define a single orifice therebetween, and

the native valve functions as a single check valve.

In an application, the tissue-engaging elements include at least a first tissue-engaging element and a second tissue-engaging element, and the first tissue-engaging element is transluminally controllable independently of the second tissue-engaging element.

In an application, the tissue-engaging elements are configured to couple the prosthetic valve support to the native leaflets without eliminating the check valve functionality, by coupling the prosthetic valve support to the native leaflets such that:

the native leaflets define two orifices therebetween, and the native valve functions as two check valves.

In an application:

the native leaflets include a first leaflet and a second leaflet,

the tissue-engaging elements include at least a first tissue-engaging element and a second tissue-engaging element,

the first tissue-engaging element is configured to be coupled to a portion of the first leaflet, and

the second tissue-engaging element is configured to be coupled to a portion of the second leaflet and to the first tissue-engaging element.

In an application, the apparatus is configured such that the first tissue-engaging element is transluminally, intracorporeally decouplable from the second tissue-engaging element.

In an application, the prosthetic valve support includes an annular upstream support portion:

shaped to define an opening therethrough,

coupled to the tissue-engaging elements,

configured to be placed against an upstream surface of the native annulus, and

configured to be transluminally, intracorporeally, coupled to the prosthetic valve.

In an application, the apparatus further includes the prosthetic valve, and the prosthetic valve includes a flexible netting at at least an upstream portion of the prosthetic valve, and the netting is configured to facilitate coupling of the prosthetic valve to the upstream support portion.

In an application, the prosthetic valve support includes one or more flexible connectors, and each tissue-engaging element is flexibly coupled to the upstream support portion by a respective flexible connector.

In an application, each flexible connector has a length, and is configured such that the length is variable while the tissue-engaging elements are coupled to the native leaflets.

In an application, the upstream support portion has a compressed configuration and an expanded configuration, and is configured (1) to be delivered to the native valve in the compressed configuration, and (2) to be expanded into the expanded configuration at the native valve.

In an application, the apparatus further includes one or more coupling leads, and the apparatus is configured such that the expansion of the upstream support portion is controllable using the coupling leads.

In an application, each coupling lead passes around at least a portion of the upstream support portion, and the apparatus is configured such that the upstream support portion is recompressible from the expanded configuration toward the compressed configuration, by pulling on the coupling leads.

In an application, the prosthetic valve support includes a downstream stabilizing element:

shaped to define an opening therethrough,

coupled to the tissue-engaging elements,

configured to be placed entirely downstream of the native annulus, and

configured to be coupled to the prosthetic valve.

In an application, the apparatus further includes the prosthetic valve, and the prosthetic valve includes a valve body and one or more valve-anchoring elements, the valve-anchoring elements being configured to sandwich the downstream stabilizing element between the valve-anchoring elements and the valve body.

In an application, the prosthetic valve support is configured to be coupled to the native leaflets such that no portion of the prosthetic valve support is disposed upstream of the native annulus.

In an application, the tissue-engaging elements include clips, each clip including a plurality of clip arms, including at least a first clip arm and a second clip arm, and configured to couple at least a portion of one of the native leaflets between the first and second clip arms.

In an application, the apparatus further includes a clip controller, configured to be advanced transluminally to the native valve, and each clip includes a clip-controller interface, configured to be reversibly coupled to the clip controller, and to facilitate extracorporeal control of the clips independently of deployment of the prosthetic valve support.

In an application, each clip is configured such that movement of at least a portion of the clip-controller interface by a first distance, changes a distance between a portion of the first clip arm and a portion of the second clip arm by a second distance that is more than 1.5 times greater than the first distance.

In an application, the tissue-engaging elements are configured to suturelessly couple the prosthetic valve support to the native leaflets.

In an application, the prosthetic valve support is configured to be transluminally, intracorporeally, couplable to the prosthetic valve.

There is further provided, in accordance with an application of the present invention, a method for use at a native valve of a subject, the native valve including at least one native leaflet that provides native check valve functionality, the method including:

transluminally delivering a prosthetic valve support to the native valve;

coupling a prosthetic valve support to the leaflet of the native valve without eliminating the native check valve functionality; and

subsequently, replacing, at least in part, the native check valve functionality with a substitute check valve functionality, by coupling a prosthetic valve to the prosthetic valve support.

In an application:

the prosthetic valve support includes at least one clip,

the clip includes two or more clip arms and a clip-controller interface, and

coupling the prosthetic valve support to the leaflet includes changing an angular disposition between the clip arms by moving the clip-controller interface.

There is further provided, in accordance with an application of the present invention, apparatus for use with a native heart valve of a subject, the apparatus including:

a first expandable prosthetic valve component, including a crimpable frame, and configured to be transcatheterally advanceable toward the native valve while the first prosthetic valve component is in a crimped state thereof;

a second expandable prosthetic valve component, including a crimpable frame, and configured to be transcatheterally advanceable toward the native valve, placeable in the native valve while the second prosthetic valve component is in a crimped state thereof, and couplable to the first prosthetic valve component, expansion of the second prosthetic valve component facilitating coupling of the second prosthetic valve component to the first prosthetic valve component; and

one or more tissue-engagement elements, coupled to at least one of the prosthetic valve components, the tissue-engagement elements configured, when the prosthetic valve component is in an expanded state thereof, to extend from the prosthetic valve component, and to inhibit a proximal movement of the prosthetic valve component.

There is further provided, in accordance with an application of the present invention, apparatus for use with a prosthetic valve for implantation at a native valve of a subject, the native valve (1) defining an orifice, (2) including at least one native leaflet, having a native beating, and (3) having a native blood flow regulation functionality, the apparatus including:

a prosthetic valve support, including:

an upstream support portion, configured to be placed against an upstream side of the native valve, to have an inner perimeter that defines an opening that is configured to receive the prosthetic valve, andat least one clip, configured to be coupled to a native leaflet of the native valve, the clip including a plurality of clip arms, at least one clip arm coupled to a clip-controller interface; and

a clip controller, couplable to the clip-controller interface, and configured to control a relative angular disposition between the clip arms.

For some applications, techniques described herein are practiced in combination with techniques described in one or more of the references cited in the Background section and Cross-references section of the present patent application.

