FIELD

The present disclosure concerns embodiments of a prosthetic heart valve.

BACKGROUND

The human heart can suffer from various valvular diseases. These valvular diseases can result in significant malfunctioning of the heart and ultimately require replacement of the native valve with an artificial valve. There are a number of known artificial valves and a number of known methods of implanting these artificial valves in humans.

Various surgical techniques may be used to replace or repair a diseased or damaged valve. Due to stenosis and other heart valve diseases, thousands of patients undergo surgery each year wherein the defective native heart valve is replaced by a prosthetic valve. Another less drastic method for treating defective valves is through repair or reconstruction, which is typically used on minimally calcified valves. The problem with surgical therapy is the significant risk it imposes on these chronically ill patients with high morbidity and mortality rates associated with surgical repair.

When the native valve is replaced, surgical implantation of the prosthetic valve typically requires an open-chest surgery during which the heart is stopped and patient placed on cardiopulmonary bypass (a so-called “heart-lung machine”). In one common surgical procedure, the diseased native valve leaflets are excised and a prosthetic valve is sutured to the surrounding tissue at the valve annulus. Because of the trauma associated with the procedure and the attendant duration of extracorporeal blood circulation, some patients do not survive the surgical procedure or die shortly thereafter. It is well known that the risk to the patient increases with the amount of time required on extracorporeal circulation. Due to these risks, a substantial number of patients with defective native valves are deemed inoperable because their condition is too frail to withstand the procedure. By some estimates, more than 50% of the subjects suffering from valve stenosis who are older than 80 years cannot be operated on for valve replacement.

Because of the drawbacks associated with conventional open-heart surgery, percutaneous and minimally-invasive surgical approaches have become widely adopted in recent years. In one technique, a prosthetic valve is configured to be implanted in a much less invasive procedure by way of catheterization. For instance, U.S. Pat. Nos. 5,411,522 and 6,730,118, which are incorporated herein by reference, describe collapsible transcatheter heart valves that can be percutaneously introduced in a compressed state on a catheter and expanded in the desired position by balloon inflation or by utilization of a self-expanding frame or stent.

An important design parameter of a transcatheter heart valve is the amount of mechanical interaction between the prosthetic frame or stent and the native anatomy at the annulus and left ventricle outflow tract (“LVOT”) level. It is desirable to reduce tissue trauma and/or mechanical stress in the native anatomy to avoid procedural-related injuries, such as LVOT, aortic and/or annulus rupture, which may occur in the region of the aortic root and the LVOT during transcatheter aortic valve replacement.

SUMMARY

An exemplary embodiment of a prosthetic heart valve can include an annular frame having an inflow end, an outflow end and a central longitudinal axis extending from the inflow end to the outflow end. The frame can include a valvular structure including two or more leaflets, each of the two or more leaflets having a leaflet inflow edge positioned at least partially outside of the frame and a leaflet outflow edge positioned within the frame, wherein at least a portion of each of the leaflet inflow edges is unsupported by the frame. Some embodiments can include an inner skirt, wherein a first portion of the inner skirt extends circumferentially around the central longitudinal axis along an inner surface of the frame and a second portion of the inner skirt extends circumferentially around the central longitudinal axis outside of the frame. In some embodiments, the portions of the leaflet inflow edges unsupported by the frame are connected to the second portion of the inner skirt.

Additionally and/or alternatively, the inner skirt can include a first set of fibers that are sufficiently stiff to impede inward bending of the second portion due to systolic pressure gradient and blood flowing from the left ventricle to the aorta. In some embodiments, the first set of fibers run parallel to the central longitudinal axis. In some embodiments, the inner skirt includes a second set of fibers that run perpendicular to the first set of fibers, wherein the first set of fibers are stiffer than the second set of fibers. In some embodiments, the first set of fibers include monofilaments. In some embodiments, the portions of the leaflet inflow edges unsupported by the frame each include an apex portion of each leaflet. In some embodiments, the frame includes at least two rows of cells defining openings having a length in an axial direction and a length of the portion of the inflow edges unsupported by the frame is equal to or greater than the length of the openings. Additionally and/or alternatively, some embodiments can include an outer sealing member mounted on the outside of the frame.

Additionally and/or alternatively, some embodiments can include an outer support layer mounted on the outside of the frame having an inflow end portion that extends axially beyond the inflow end of the frame, and the portion of the leaflet inflow edges unsupported by the frame is connected to the inflow end portion of the outer support layer.

Some embodiments of an implantable prosthetic valve can include an annular frame having an inflow end, an outflow end and a central longitudinal axis extending from the inflow end to the outflow end, an inner skirt, wherein a first portion of the inner skirt extends circumferentially around the central longitudinal axis along an inner surface of the frame and a second portion of the inner skirt extends circumferentially around the central longitudinal axis outside of the frame and a valvular structure including two or more leaflets, each of the two or more leaflets having a leaflet inflow edge positioned at least partially outside of the frame and a leaflet outflow edge positioned within the frame, wherein at least a portion of each of the leaflet inflow edges are connected to the second portion of the inner skirt.

In some embodiments, the inner skirt includes a first set of fibers and a second set of fibers that runs perpendicular to the first set of fibers, wherein the first set of fibers is stiffer than the second set of fibers. In some embodiments, the frame includes a row of cells defining openings having a length in an axial direction and further wherein a length of the second portion is equal to or greater than the length of the openings. In some embodiments, an outer skirt can be connected to the second portion of the inner skirt. In some embodiments, the portions of the leaflet inflow edges unsupported by the frame include an apex portion of each leaflet.

Some embodiments of an implantable prosthetic valve can include an annular frame having an inflow end, an outflow end and a central longitudinal axis extending from the inflow end to the outflow end, a support layer, wherein a first portion of the support layer extends circumferentially around the central longitudinal axis along an outer surface of the frame and a second portion of the support layer extends circumferentially around the central longitudinal axis axially beyond the inflow end of the frame, and a valvular structure wherein at least a portion of the valvular structure is connected to the second portion of the support layer and is unsupported by the frame. In some embodiments, an outer skirt can be connected to the second portion of the support layer at an inflow end of the outer skirt. In some embodiments, the support layer includes a first set of fibers and a second set of fibers that runs perpendicular to the first set of fibers, wherein the first set of fibers is stiffer than the second set of fibers. In some embodiments, the valvular structure comprises a plurality of leaflets and the first set of fibers includes monofilaments. In some embodiments, the at least a portion of the valvular structure unsupported by the frame includes an apex portion of each leaflet.

The foregoing and other objects, features, and advantages of the disclosure will become more apparent from the following detailed description, which proceeds with reference to the accompanying figures.

