Patent Grant
8632586
The present invention relates to implantable devices. More particularly, it relates to a valve prosthesis for cardiac implantation or for implantation in other body ducts.
There are several known prosthetic valves that have been previously described. U.S. Pat. No. 5,411,552 (Andersen et al.), entitled VALVE PROSTHESIS FOR IMPLANTATION IN THE BODY AND CATHETER FOR IMPLANTING SUCH VALVE PROSTHESIS, discloses a valve prosthesis comprising a stent made from an expandable cylinder-shaped thread structure comprising several spaced apices. The elastically collapsible valve is mounted on the stent with the commissural points of the valve secured to the projecting apices, which prevents the valve from turning inside out. Deployment of the valve can be achieved by using an inflatable balloon which in its deflated state is used to carry about it the valve structure to its position and, when inflated, deploys the stent in position to its final size. See, also, U.S. Pat. No. 6,168,614 (Andersen et al.) entitled VALVE PROSTHESIS FOR IMPLANTATION IN THE BODY and U.S. Pat. No. 5,840,081 (Andersen et al.), entitled SYSTEM AND METHOD FOR IMPLANTING CARDIAC VALVES.
In PCT/EP97/07337 (Letac, Cribier et al.), published as WO 98/29057, entitled VALVE PROSTHESIS FOR IMPLANTATION IN BODY CHANNELS, there is disclosed a valve prosthesis comprising a collapsible valve structure and an expandable frame on which the valve structure is mounted. The valve structure is composed of a valvular tissue compatible with the human body and blood, the valvular tissue being sufficiently supple and resistant to allow the valve structure to be deformed from a closed state to an opened state. The valvular tissue forms a continuous surface and is provided with guiding means formed or incorporated within, the guiding means creating stiffened zones which induce the valve structure to follow a patterned movement in its expansion to its opened state and in its turning back to its closed state. The valve structure can be extended to an internal cover which is fastened to the lower part of the valve structure to prevent regurgitation.
There are several known methods currently used for replacing aortic valves and several types of artificial prosthetic devices. Mechanical valves are commonly used in several different designs (single and double flap) manufactured by well-known companies such as St. Jude, Medtronic, Sulzer, and others. Some of the main disadvantages of these devices are: a need for permanent treatment of anticoagulants, noisy operation, and a need for a large-scale operation to implant.
There is a wide range of biologically based valves made of natural valves or composed of biological materials such as pericardial tissue. These too are made and marketed by well-known companies such as Edwards Lifesciences, Medtronic, Sulzer, Sorin, and others.
Polymer valves are new and are not yet in use, but several companies are in the process of developing such products. A new type of prosthesis is being considered, based on artificial polymer materials such as polyurethane.
The present invention introduces several novel structural designs for implantable valves. An aspect of the present invention deals with the possibility of implanting the valve percutaneously, i.e., inserting the valve assembly on a delivery device similar to a catheter, then implanting the valve at the desired location via a large blood vessel such as the femoral artery, in a procedure similar to other known interventional cardiovascular procedures. The percutaneous deployment procedure and device has an impact on the product design in several parameters, some of which are explained hereinafter.
The percutaneous implantation of medical devices and particularly prosthetic valves is a preferred surgical procedure for it involves making a very small perforation in the patient's skin (usually in the groin or armpit area) under local anesthetic and sedation, as opposed to a large chest surgery incision, which requires general anesthesia, opening a large portion of the chest, and cardiopulmonary bypass. This percutaneous procedure is therefore considered safer.
The present invention provides a series of new concepts in the field of aortic valves and other human valves.
It is therefore thus provided, in accordance with a preferred embodiment of the present invention, a valve prosthesis device suitable for implantation in body ducts, the device comprising:
a support stent, comprised of a deployable construction adapted to be initially crimped in a narrow configuration suitable for catheterization through the body duct to a target location and adapted to be deployed by exerting substantially radial forces from within by means of a deployment device to a deployed state in the target location, the support stent provided with a plurality of longitudinally rigid support beams of fixed length; and
a valve assembly comprising a flexible conduit having an inlet end and an outlet, made of pliant material attached to the support beams providing collapsible slack portions of the conduit at the outlet,
whereby when flow is allowed to pass through the valve prosthesis device from the inlet to the outlet the valve assembly is kept in an open position, whereas a reverse flow is prevented as the collapsible slack portions of the valve assembly collapse inwardly providing blockage to the reverse flow.
Furthermore, in accordance with another preferred embodiment of the present invention, the support stent comprises an annular frame.
Furthermore, in accordance with another preferred embodiment of the present invention, said valve assembly has a tricuspid configuration.
Furthermore, in accordance with another preferred embodiment of the present invention, said valve assembly is made from biocompatible material.
Furthermore, in accordance with another preferred embodiment of the present invention, the valve assembly is made from pericardial tissue, or other biological tissue.
Furthermore, in accordance with another preferred embodiment of the present invention, said valve assembly is made from biocompatible polymers.
Furthermore, in accordance with another preferred embodiment of the present invention, the valve assembly is made from materials selected from the group consisting of polyurethane and polyethylene terephthalate (PET).
Furthermore, in accordance with another preferred embodiment of the present invention, said valve assembly comprises a main body made from PET (polyethylene terephthalate) and leaflets made from polyurethane.
Furthermore, in accordance with another preferred embodiment of the present invention, said support stent is made from nickel titanium.
Furthermore, in accordance with another preferred embodiment of the present invention, the support beams are substantially equidistant and substantially parallel so as to provide anchorage for the valve assembly.
Furthermore, in accordance with another preferred embodiment of the present invention, the support beams are provided with bores so as to allow stitching or tying of the valve assembly to the beams.
Furthermore, in accordance with another preferred embodiment of the present invention, the support beams are chemically adhered to the support stent.
Furthermore, in accordance with another preferred embodiment of the present invention, said valve assembly is riveted to the support beams.
Furthermore, in accordance with another preferred embodiment of the present invention, said valve assembly is stitched to the support beams.
Furthermore, in accordance with another preferred embodiment of the present invention, said beams are manufactured by injection using a mold, or by machining.
Furthermore, in accordance with another preferred embodiment of the present invention, said valve assembly is rolled over the support stent at the inlet.
Furthermore, in accordance with another preferred embodiment of the present invention, said valve device is manufactured using forging or dipping techniques.
Furthermore, in accordance with another preferred embodiment of the present invention, said valve assembly leaflets are longer than needed to exactly close the outlet, thus when they are in the collapsed state substantial portions of the leaflets fall on each other creating better sealing.
Furthermore, in accordance with another preferred embodiment of the present invention, said valve assembly is made from coils of a polymer, coated by a coating layer of same polymer.
Furthermore, in accordance with another preferred embodiment of the present invention, said polymer is polyurethane.
Furthermore, in accordance with another preferred embodiment of the present invention, the support stein is provided with heavy metal markers so as to enable tracking and determining the valve device position and orientation.
Furthermore, in accordance with another preferred embodiment of the present invention, the heavy metal markers are selected from gold, platinum, iridium, or tantalum.
Furthermore, in accordance with another preferred embodiment of the present invention, the valve assembly leaflets are provided with radio-opaque material at the outlet, so as to help tracking the valve device operation in vivo.
Furthermore, in accordance with another preferred embodiment of the present invention, said radio-opaque material comprises gold thread.
Furthermore, in accordance with another preferred embodiment of the present invention, the diameter of said support stent, when fully deployed is in the range of from about 19 to about 25 mm.
Furthermore, in accordance with another preferred embodiment of the present invention, the diameter of said support stent may be expanded from about 4 to about 25 mm.
Furthermore, in accordance with another preferred embodiment of the present invention, the support beams are provided with bores and wherein the valve assembly is attached to the support beams by means of U-shaped rigid members that are fastened to the valve assembly and that are provided with extruding portions that fit into matching bores on the support beams.
Furthermore, in accordance with another preferred embodiment of the present invention, the support beams comprise rigid support beams in the form of frame construction, and the valve assembly pliant material is inserted through a gap in the frame and a fastening rod is inserted through a pocket formed between the pliant material and the frame and holds the valve in position.
Furthermore, in accordance with another preferred embodiment of the present invention, the main body of the valve assembly is made from coiled wire coated with coating material.
Furthermore, in accordance with another preferred embodiment of the present invention, the coiled wire and the coating material is made from polyurethane.
Furthermore, in accordance with another preferred embodiment of the present invention, a strengthening wire is interlaced in the valve assembly at the outlet of the conduit so as to define a fault line about which the collapsible slack portion of the valve assembly may flap.
Furthermore, in accordance with another preferred embodiment of the present invention, the strengthening wire is made from nickel titanium alloy.
Furthermore, in accordance with another preferred embodiment of the present invention, there is provided a valve prosthesis device suitable for implantation in body ducts, the device comprising a main conduit body having an inlet and an outlet and pliant leaflets attached at the outlet so that when a flow passes through the conduit from the inlet to the outlet the leaflets are in an open position allowing the flow to exit the outlet, and when the flow is reversed the leaflets collapse so as to block the outlet, wherein the main body is made from PET and collapsible leaflets are made form polyurethane.
Furthermore, in accordance with another preferred embodiment of the present invention, support beams made from polyurethane are provided on the main body and wherein the leaflets are attached to the main body at the support beams.
Furthermore, in accordance with another preferred embodiment of the present invention, said support beams are chemically adhered to the main body.
Furthermore, in accordance with another preferred embodiment of the present invention, there is provided a valve prosthesis device suitable for implantation in body ducts, the device comprising:
a support stent, comprised of a deployable construction adapted to be initially crimped in a narrow configuration suitable for catheterization through the body duct to a target location and adapted to be deployed by exerting substantially radial forces from within by means of a deployment device to a deployed state in the target location, the support stent provided with a plurality of longitudinally rigid support beams of fixed length;
a valve assembly comprising a flexible conduit having an inlet end and an outlet, made of pliant material attached to the support beams providing collapsible slack portions of the conduit at the outlet; and
substantially equidistant rigid support beams interlaced or attached to the slack portion of the valve assembly material, arranged longitudinally.
Furthermore, in accordance with another preferred embodiment of the present invention, there is provided a crimping device for crimping the valve device described above or in Claim 1, the crimping device comprising a plurality of adjustable plates that resemble a typical SLR (Single Lens Reflex) camera variable restrictor, each provided with a blade, that are equally dispersed in a radial symmetry but each plate moves along a line passing off an opening in the center, all plates equidistant from that center opening.
Furthermore, in accordance with another preferred embodiment of the present invention, the multiple plates are adapted to move simultaneously by means of a lever and transmission.
Furthermore, in accordance with another preferred embodiment of the present invention, there is provided a method for deploying an implantable prosthetic valve device from the retrograde approach (approaching the aortic valve from the descending aorta) or from the antegrade approach (approaching the aortic valve from the left ventricle after performing a trans-septal puncture) at the natural aortic valve position at the entrance to the left ventricle of a myocardium of a patient, the method comprising the steps of:
(a) providing a balloon catheter having a proximal end and a distal end, having a first and second independently inflatable portions, the first inflatable portion located at the distal end of the catheter and the second inflatable portion adjacently behind the first inflatable portion;
(b) providing a guiding tool for guiding the balloon catheter in the vasculature of the patient;
(c) providing a deployable implantable valve prosthesis device adapted to be mounted on the second inflatable portion of the balloon catheter;
(d) for the retrograde approach, guiding the balloon catheter through the patient's aorta using the guiding tool, the valve device mounted over the second inflatable portion of the balloon catheter until the first inflatable portion of the balloon catheter is inserted into the left ventricle, whereas the second inflatable portion of the balloon catheter is positioned at the natural aortic valve position;
(e) for the antegrade approach, guiding the balloon catheter through the patient's greater veins, right atrium, left atrium, and left ventricle using the guiding tool, the valve device mounted over the second inflatable portion of the balloon catheter until the first inflatable portion of the balloon catheter is inserted into the left ventricle, whereas the second inflatable portion of the balloon catheter is positioned at the natural aortic valve position;
(f) inflating the first inflatable portion of the balloon catheter so as to substantially block blood flow through the natural aortic valve and anchor the distal end of the balloon catheter in position;
(g) inflating the second inflatable portion of the balloon catheter so as to deploy the implantable prosthetic valve device in position at the natural aortic valve position;
(h) deflating the first and second inflatable portions of the balloon catheter; and
(i) retracting the balloon catheter and removing it from the patient's body.
Furthermore, in accordance with another preferred embodiment of the present invention, the guiding tool comprises a guide wire.
Furthermore, in accordance with another preferred embodiment of the present invention, there is provided a method for deploying an implantable prosthetic valve device at the natural aortic valve position at the entrance to the left ventricle of a myocardium of a patient, the method comprising the steps of:
(a) providing a balloon catheter having a proximal end and a distal end, having a first and second independently inflatable portions, the first inflatable portion located at the distal end of the catheter and the second inflatable portion adjacently behind the first inflatable portion;
(b) providing a guiding tool for guiding the balloon catheter in the vasculature of the patient;
(c) providing a deployable implantable valve prosthesis device adapted to be mounted on the first inflatable portion of the balloon catheter, and a deployable annular stent device adapted to be mounted over the second inflatable portion of the balloon catheter, the deployable implantable valve prosthesis device and the deployable annular stent kept at a predetermined distant apart;
(d) guiding the balloon catheter through the patient's aorta using the guiding tool, the valve device mounted over the first inflatable portion of the balloon catheter and the deployable annular stent mounted over the second inflatable portion of the balloon catheter, until the first inflatable portion of the balloon catheter is positioned at the natural aortic valve position;
(e) inflating the second inflatable portion of the balloon catheter so that the deployable stent device is deployed within the aorta thus anchoring the deployable annular stent and the coupled valve device in position;
(f) inflating the first inflatable portion of the balloon catheter so as to deploy the implantable prosthetic valve device in position at the natural aortic valve position;
(g) deflating the first and second inflatable portions of the balloon catheter; and
(h) retracting the balloon catheter and removing it from the patient's body.
Furthermore, in accordance with another preferred embodiment of the present invention, a valve prosthesis device suitable for implantation in body ducts comprises:
an expandable support frame, the support frame provided with a plurality of longitudinally rigid support beams of fixed length; and
a valve assembly comprising a flexible conduit having an inlet end and an outlet, made of pliant material attached to the support beams providing collapsible slack portions of the conduit at the outlet,
whereby when flow is allowed to pass through the valve prosthesis device from the inlet to the outlet the valve assembly is kept in an open position, whereas a reverse flow is prevented as the collapsible slack portions of the valve assembly collapse inwardly providing blockage to the reverse flow.
Furthermore, in accordance with another preferred embodiment of the present invention, the support frame comprises a deployable construction adapted to be initially crimped in a narrow configuration suitable for catheterization through the body duct to a target location and adapted to be deployed by exerting substantially radial forces from within by means of a deployment device to a deployed state in the target location.
Furthermore, in accordance with another preferred embodiment of the present invention, the support beams have a U-shaped cross section.
Furthermore, in accordance with another preferred embodiment of the present invention, a holder is used to secure the plaint material to the support beams.
Furthermore, in accordance with another preferred embodiment of the present invention, the support frame comprises three segments that form a circular assembly when assembled.
Furthermore, in accordance with another preferred embodiment of the present invention, the support beams point inwardly with respect to a central longitudinal axis of the device.
Furthermore, in accordance with another preferred embodiment of the present invention, the device is further provided with a restricting tapered housing, for housing it in a crimped state.
Furthermore, in accordance with another preferred embodiment of the present invention, hooks are provided to secure the device in position after it is deployed.
Furthermore, in accordance with another preferred embodiment of the present invention, the support beams comprise longitudinal bars having a narrow slit used as the commissural attachment so that extensions the pliant material are tightly inserted through it.
Furthermore, in accordance with another preferred embodiment of the present invention, the extensions of the pliant material are wrapped about rigid bars serving as anchorage means.
Furthermore, in accordance with another preferred embodiment of the present invention, extensions of the pliant material are sutured to each other at the rigid bars.
Furthermore, in accordance with another preferred embodiment of the present invention, a bottom portion of the pliant material is attached to the inlet.
Furthermore, in accordance with another preferred embodiment of the present invention, the support beams are each provided with a rounded pole, forming a loop through which the pliant material is inserted.
Furthermore, in accordance with another preferred embodiment of the present invention, the pliant material is provided with longitudinal bars attached to the pliant material at positions assigned for attachment to the support frame, in order to prevent localized stress from forming.
Furthermore, in accordance with another preferred embodiment of the present invention, the device is further provided with longitudinal bars having protrusions that are inserted in bores in the pliant material, a sheet of PET and through bores provided on the support beams.
Furthermore, in accordance with another preferred embodiment of the present invention, pliant material is sutured leaving the slack portions free of sutures.
Furthermore, in accordance with another preferred embodiment of the present invention, a connecting member with a split portion is used to connect leaflets of the pliant material to the support beams, the split connecting member compressing the pliant material in position.
Furthermore, in accordance with another preferred embodiment of the present invention, a portion of the connecting member is perpendicular to the split portion.
Furthermore, in accordance with another preferred embodiment of the present invention, the support frame is provided with metallic members coupled to the stent and rigid members are positioned on two opposite sides of the metallic member and held against each other holding portion of the pliant material between them, sutured, the metallic members wrapped with PET.
Furthermore, in accordance with another preferred embodiment of the present invention, the device is further provided with spring in order to reduce wear of the pliant material.
Furthermore, in accordance with another preferred embodiment of the present invention, the spring is provided with a spiral.
Furthermore, in accordance with another preferred embodiment of the present invention, the spring is made from stainless steel.
Furthermore, in accordance with another preferred embodiment of the present invention, the spring is attached to slots provided on the support frames.
Furthermore, in accordance with another preferred embodiment of the present invention, the pliant material is sutured to the support frame forming pockets.
Furthermore, in accordance with another preferred embodiment of the present invention, attachment bars are provided on the stent support at a portion of the stent close to the outlet, onto which the pliant material is coupled, and wherein the pliant material is attached circumferentially to the inlet, leaving slack pliant material.
Furthermore, in accordance with another preferred embodiment of the present invention, the outlet is tapered with respect to the inlet.
Furthermore, in accordance with another preferred embodiment of the present invention, the support frame at the outlet is wider in diameter than the pliant material forming the outlet.
Furthermore, in accordance with another preferred embodiment of the present invention, the pliant material is reinforced using PET.
Furthermore, in accordance with another preferred embodiment of the present invention, the support frame is a tube having an inner wall, having sinusoidal fold lines, wherein the pliant material is sutured to the inner wall of the tube along suture lines.
Furthermore, in accordance with another preferred embodiment of the present invention, additional piece of PET is added below the suture lines.
Furthermore, in accordance with another preferred embodiment of the present invention, the device is incorporated with an angioplasty balloon.
Finally, in accordance with another preferred embodiment of the present invention, balloon has a central longitudinal axis that runs along a flow path through the device, and a perimeter, the balloon comprising four inflatable portions, one portion located along a central axis and the other three located on the perimeter, the pliant material in the form of leaflets is distributed about the perimeter.
To better understand the present invention and appreciate its practical applications, the following Figures are provided and referenced hereafter. It should be noted that the Figures are given as examples only and in no way limit the scope of the invention as defined in the appended claims.
a to 6e illustrate manufacturing of an implantable valve by forging according to the present invention;
a and 7b demonstrate composite valve, which has polyurethane (PU) leaflets and PET tubular-crown shaped construction, according to the present invention;
a and 8b depict a manufacture process of a composite valve made of flexible PU leaflets, rigid PU construction for mounting and a PET tubular end;
i demonstrate different methods of attachment between the valve and stent according to the present invention;
a to 11c illustrate a valve mounted on a stent with an extra support, which improves the force distribution on the valve material and facilitates prolonged durability of the valve, according to the present invention;
a to 12c depict a valve with rigid supports according to the present invention, located substantially in the center of its leaflets. This design allows the valve leaflets to perform without outer support;
a to 13c illustrate the manufacturing of a reinforced PU tube composed of strong fiber from PU, PET or other and a softer PU coating, for serving as the supporting structure;
a to 14c demonstrate incorporation of heavy metal markers on the stent, according to the present invention. These markers allow orientation control while positioning the device at the required location;
a to 15c demonstrate a valve with radio-opaque coating, according to the present invention, which allows imaging of the valve motion under angiogram;
a to 16c illustrate a procedure, which helps in accurate positioning the valve device with respect to the longitudinal orientation;
a and 17b describe a valve device according to the present invention, comprising one valve assembly mounted on a stent and an additional portion with a stent only. This allows placing the device in a way that coronaries are not blocked, longitudinal positioning thus becomes less sensitive and the extra stent decreases the risk of device migration within the vasculature;
a and 18b demonstrate a crimping device according to the present invention, which can crimp a valve device in the operating theater as part of the implantation procedure;
a to 19c depict a crimping machine according to the present invention, similar to the one described in
a and 20b demonstrate a valve according to the present invention, made of a tube mounted on a stent. During systole the tube is fully open and during diastole the tube collapses according to the mounting geometry providing tight sealing;
a to 23e depict stages in a method of manufacturing an implantable prosthetic valve in accordance with another preferred embodiment of the present invention;
a to 24c illustrate a support frame of an implantable prosthetic valve having means for mounting valve leaflets in accordance with a preferred embodiment of the present invention that can form a tricuspid valve.
a to 25d illustrate an implantable prosthetic valve in accordance with another preferred embodiment of the present invention.
a to 26c illustrate a tricuspid valve in accordance with yet another preferred embodiment of the present invention, provided with a self-expandable frame.
a and 29b illustrate an isometric view and an upper cross-sectional view, respectively, of an attachment assembly of a valve's frame to leaflets in accordance with a preferred embodiment of the present invention;
a to 30c illustrate an isometric view, a cross-sectional view and a flattened view, respectively, of an attachment assembly of a valves frame to leaflets in accordance with another preferred embodiment of the present invention.
a and 31b illustrate an exploded view and an isometric view, respectively, of a commissural attachment in accordance with a preferred embodiment of the present invention depicting the attachment technique;
a through 32c illustrate an isometric view of an attachment between leaflets and the frame in accordance with yet another preferred embodiment of the present invention;
a to 33d illustrate different views and portions of an attachment between a pericardium and a frame in accordance with yet another preferred embodiment of the present invention, demonstrating another method of attachment in accordance with the preferred embodiment;
a to 34c illustrate an isometric view of an attachment between a pericardium and a valve in accordance with yet another preferred embodiment of the present invention demonstrating another method of attachment. In
a to 35c illustrate an isometric and cross-sectional upper views, respectively, of attachment techniques between a pericardium leaflet and a valve's frame in accordance with another preferred embodiment of the present invention;
a and 35b illustrate an isometric view of a commissural assembly in accordance with a preferred embodiment of the present invention demonstrating a method of fowling one;
a to 37c illustrates a commissural assembly in accordance with another preferred embodiment of the present invention, where the connecting bar functions as a flexible support and has integral attachment means to the frame.
a to 38g illustrate isometric views of flexible commissural supports and the method of attaching them to a pericardium and a frame and valve in accordance with preferred embodiments of the present invention;
a and 39b illustrate an isometric view of a commissural attachment in accordance with yet another preferred embodiment of the present invention, demonstrating the attachment of the pericardium to the support by means of a shaped compressing member;
a to 40c illustrate an isometric view of a bicuspid valve mounted on a frame in accordance with yet another preferred embodiment of the present invention.
a to 41d illustrate isometric views of an implantable prosthesis tricuspid valve in accordance with yet another preferred embodiment of the present invention;
a and 42b illustrate an isometric view of an implantable prosthetic valve in accordance with yet another preferred embodiment of the present invention, having a different commissural attachment.
a and 43b illustrate an isometric view of an implantable prosthetic valve in accordance with yet another preferred embodiment of the present invention.
a to 44c illustrate an isometric view of an implantable prosthetic valve in accordance with yet another preferred embodiment of the present invention, with additional pieces of PET used for sealing and protecting the pericardium;
a to 45d illustrate an isometric view of an implantable prosthetic valve in accordance with yet another preferred embodiment of the present invention, having leaflets sutured to a pre-shaped PET tube and optional leaflet-tube attachments in details;
a and 46b illustrate an exploded view and an upper cross-sectional view of an implantable prosthetic valve assembly in accordance with yet another preferred embodiment of the present invention;
a to 47c illustrate a partial cross-sectional side view of an inflating balloon in accordance with a preferred embodiment of the present invention. The balloon is a part of an implantable prosthetic valve delivery system.
a and 48b illustrate a partial cross-sectional side view and an upper cross-sectional view of an inflating balloon in accordance with another preferred embodiment of the present invention.
A main aspect of the present invention is the introduction of several novel designs for an implantable prosthetic valve. Another aspect of the present invention is the disclosure of several manufacturing methods for implantable prosthetic valves in accordance with the present invention. A further aspect of the present invention is the provision of novel deployment and positioning techniques suitable for the valve of the present invention.
Basically the implantable prosthetic valve of the present invention comprises a leafed-valve assembly, preferably tricuspid but not limited to tricuspid valves only, consisting of a conduit having an inlet end and an outlet, made of pliant material arranged so as to present collapsible walls at the outlet. The valve assembly is mounted on a support structure such as a stent adapted to be positioned at a target location within the body duct and deploy the valve assembly by the use of deploying means, such as a balloon catheter or similar devices. In embodiments suitable for safe and convenient percutaneous positioning and deployment the annular frame is able to be posed in two positions, a crimped position where the conduit passage cross-section presented is small so as to permit advancing the device towards its target location, and a deployed position where the frame is radial extended by forces exerted from within (by deploying means) so as to provide support against the body duct wall, secure the valve in position and open itself so as to allow flow through the conduit.
The valve assembly can be made from biological matter, such as a natural tissue, pericardial tissue or other biological tissue. Alternatively, the valve assembly may be made form biocompatible polymers or similar materials. Homograph biological valves need occasional replacement (usually within 5 to 14 years), and this is a consideration the surgeon must take into account when selecting the proper valve implant according to the patient type. Mechanical valves, which have better durability qualities, carry the associated risk of long-term anticoagulation treatment.
The frame can be made from shape memory alloys such as nickel titanium (nickel titanium shape memory alloys, or NiTi, as marketed, for example, under the brand name Nitinol), or other biocompatible metals. The percutaneously implantable embodiment of the implantable valve of the present invention has to be suitable for crimping into a narrow configuration for positioning and expandable to a wider, deployed configuration so as to anchor in position in the desired target location.
The support stent is preferably annular, but may be provided in other shapes too, depending on the cross-section shape of the desired target location passage.
Manufacturing of the implantable prosthetic valve of the present invention can be done in various methods, by using pericardium or, for example, by using artificial materials made by dipping, injection, electrospinning, rotation, ironing, or pressing.
The attachment of the valve assembly to the support stent can be accomplished in several ways, such as by sewing it to several anchoring points on the support frame or stent, or riveting it, pinning it, adhering it, or welding it, to provide a valve assembly that is east or molded over the support frame or stent, or use any other suitable way of attachment.
To prevent leakage from the inlet it is optionally possible to roll up some slack wall of the inlet over the edge of the frame so as to present rolled-up sleeve-like portion at the inlet.
Furthermore, floating supports may be added to enhance the stability of the device and prevent it from turning inside out.
An important aspect of certain embodiments of the present invention is the provision of rigid support beams incorporated with the support stent that retains its longitudinal dimension while the entire support stent may be longitudinally or laterally extended.
The aforementioned embodiments as well as other embodiments, manufacturing methods, different designs and different types of devices are discussed and explained below with reference to the accompanying drawings. Note that the drawings are only given for the purpose of understanding the present invention and presenting some preferred embodiments of the present invention, but this does in no way limit the scope of the present invention as defined in the appended claims.
Reference is now made to
In the embodiment shown in
Note that the entire valve structure is adapted to be radially crimped and radially expanded, and this lends to provide ease of navigation through narrow passages in the vasculature during positioning of the device and adequate deployment on the final location. This is made possible by the provision of a collapsible support stent structure. However, the support beams remain at all times constant at their length and thus are suitable for serving as the pliable valve assembly's anchorage. The valve assembly is attached to the support stent at the support beams, and due to their constant length there is no need for slack material as the attachment points (25) remain at constant distances regardless of the position of the valve device (crimped or deployed). This is an important feature for this means that the manufacturer of the valve device can make sure the valve assembly is secured and fastened to the support stent at all times. In prior art implantable valve devices the entire support structure changes its dimensions from its initial first crimped position and final deployed position, and this means that in the attachment of the valve assembly to the support structure one must take into consideration these dimension changes and leave slack material so that upon deployment of the device the valve assembly does not tear or deform. In the valve device of the present invention there is no relative movement between the valve assembly and the support beams (along the longitudinal central axis of the device). As a result, the valve device of the present invention acquires greater durability and is capable of withstanding the harsh conditions prevailing within the vasculature and especially the millions of cycles of stress applied by the blood pressure.
The fixed attachment of the valve assembly to the support stent in the valve device of the present invention results in greater stability, enhanced safety, better sealing and consequently longer lifespan. The novel design of the valve device of the present invention leads to longitudinal strength and rigidity whereas its collapsible support structure results in radial flexibility.
a to 6c illustrate manufacturing an implantable valve by forging. A suitable tubularly shaped material 74 is placed tightly on a tubular portion 68 of mandrel 67, covering the cusp portion 69. Flexible inserts 76 are pressed to mandrel 67, forging the tubular material to mandrel shape 80. A tapered ring 70 holds the flexible inserts in place as the whole mold is placed in a hot oven regulated to a desired temperature, which is lower than the material's melting point.
a and 7b demonstrate a method of manufacturing a composite valve, which has PU leaflets and PET tubular construction with a crown shape. PU is an excellent fatigue resistant material but is sensitive to tear. The PU is reinforced by the PET crown to allow safe attachment to a stent by means of stitching, riveting, or any other suitable attachment method. A PET crown 86 is placed on a mandrel 87, which is then (turned and) dipped in a container of dissolved PU. The manufactured device is a valve assembly having leaflets 88 composed of pure PU, and thus fatigue resistant, and a main body made of PET with protruding attachment portions 90 suitable for attachment built in the PU.
a and 8b demonstrate a method of manufacturing a composite valve, which is based on flexible PU 92 for as the main body of the valve, rigid PU support beams 94 serving for the attachment area, and PET sleeve 96 portions for the valve inlet. The need for a rigid portion for attachment (support beams 94) is explained by the tendency of the flexible, fatigue resistant material to tear as already explained. The advantage of the stiff PU support beams is that they are chemically adhered to the main body, and this improves the overall durability of the valve due to reduction of inner forces and friction in the attachment area specially attachment between two different materials. The valve is dipped in the method mentioned with reference to
i demonstrate different methods of attachment between a valve assembly and the support stents. A valve assembly 99 shown in
e to 9g show an attachment method comprising shaped rigid members 116, preferably made from metal, which tightly hold the PU valve material 118 by fitting in between a PU U-shaped nest 120 and are attached to a stent 122 by extruding portions 124 that are provided on U-shaped rigid member 116, which fit the bores 126 of the support beam 128 of the stent 122.
a to 11c illustrate a valve assembly mounted on a support stent 144 with interlaced strengthening wire 146, which improves the force distribution on the valve material and facilitates prolonged durability of the valve. The support is in the form of a wire, which has a crown shape as the shape of the three cusp valve base 148, it also has the ability to be crimped 150 to a small diameter, together with the stent, valve and balloon, as shown in
a to 12c depict a valve device provided with a stent 159 and substantially equidistant rigid support beams 160, interlaced or attached to the slack portion of the valve assembly material 161, arranged longitudinally. This design allows the valve leaflets to perform without outer support. The support in standard valves is by tying the upper edge of the cusp to a rigid embodiment, so that it reacts to the load as a suspension bridge. In this new design the prevention of collapsing is achieved similar to an Indian tent, i.e., the rigid supports lean on each other 162 when the valve is closed but do not interfere in opening 164 when the valve is open.
a to 13c illustrate the manufacturing of a valve assembly in accordance with another preferred embodiment of the present invention. At first a polyurethane thread line 170 is fed from a PU supply 172, and coiled around a cylindrical drum 174 to form coil 176. Then, drum 174 with coil 176 is dipped in a PU bath 177, and a second layer 178 of the PU coats coil 176, making it a stronger construction capable of withstanding tearing forces both laterally and in other directions. Incorporating two different types of materials—such as PU and PET—may render greater durability and endurance to the valve assembly. This material is an alternative material to be used in the forging method shown in
c demonstrate the incorporation of heavy metal markers on the stent, which markers allow observation and thereby adjustment of orientation while placing the device in the required location. Heavy metals are radiopaque, that is, they are conspicuous on an angioscopic image, which is a two-dimensional image. Since the coronary artery ostia 237 and 238 are located near the typical valve deployment location and must stay open, it is extremely important to make sure that the deployed valve assembly is not blocking a coronary ostium. In some cases the stent is lower than the ostium and in those cases it will stay open, but in some cases as shown in these figures it is necessary to make sure that the stent portion 239 that is connecting the valve supports 235 is opposite the coronary ostia, and in that way the blood supply is preserved through the stent struts. Two heavy metal markers 232 are attached at the outlet side, one marker 230 at the inlet side. It is possible to adjust the angiogscopic view to the plane of the left coronary as shown in
a to 15c illustrate a valve with a portion of radio-opaque material 267 such as a thread of gold at the sealing edge. When a valve is implanted, it is very important to have clear indications of how the valve is functioning in vivo; pressure measurements, flow visualization, and doppler measurements are utilized. It is also possible to examine the valve by ultrasound methods, however, observing the opening and closing of the valve cusps on a monitor.
a to 16c illustrate a procedure, which helps in placing the device in the longitudinal position. It is very important to place the device in the correct longitudinal position, for if it is too deep in the left ventricle it may interfere with the mitral valve function by improper closing or function of the valve. If it is positioned too high it may migrate, it may leak via the sinus cavities, which are located around it, and/or it may block the coronaries. It is a necessary task to position the valve prosthesis in a narrow target location. In
The method for deploying an implantable prosthetic valve device at the natural aortic valve position at the entrance to the left ventricle of a myocardium of a patient, as depicted in
(a) providing a balloon catheter having a proximal end and a distal end, having a first and second independently inflatable portions, the first inflatable portion located at the distal end of the catheter and the second inflatable portion adjacently behind the first inflatable portion;
(b) providing a guiding tool for guiding the balloon catheter in the vasculature of the patient;
(c) providing a deployable implantable valve prosthesis device adapted to be mounted on the second inflatable portion of the balloon catheter
(d) guiding the balloon catheter through the patient's aorta using the guiding tool, the valve device mounted over the second inflatable portion of the balloon catheter until the first inflatable portion of the balloon catheter is inserted into the left ventricle, whereas the second inflatable portion of the balloon catheter is positioned at the natural aortic valve position;
(e) inflating the first inflatable portion of the balloon catheter so as to substantially block blood flow through the natural aortic valve and anchor the distal end of the balloon catheter in position;
(f) inflating the second inflatable portion of the balloon catheter so as to deploy the implantable prosthetic valve device in position at the natural aortic valve position;
(g) deflating the first and second inflatable portions of the balloon catheter; and
(h) retracting the balloon catheter and removing it from the patient's body.
The method for deploying an implantable prosthetic valve device at the natural aortic valve position at the entrance to the left ventricle of a myocardium of a patient, as depicted in
(a) providing a balloon catheter having a proximal end and a distal end, having a first and second independently inflatable portions, the first inflatable portion located at the distal end of the catheter and the second inflatable portion adjacently behind the first inflatable portion;
(b) providing a guiding tool for guiding the balloon catheter in the vasculature of the patient;
(c) providing a deployable implantable valve prosthesis device adapted to be mounted on the first inflatable portion of the balloon catheter, and a deployable annular stent device adapted to be mounted over the second inflatable portion of the balloon catheter, the deployable implantable valve prosthesis device and the deployable annular stent kept at a predetermined distant apart;
(d) guiding the balloon catheter through the patient's aorta using the guiding tool, the valve device mounted over the first inflatable portion of the balloon catheter and the deployable annular stent mounted over the second inflatable portion of the balloon catheter, until the first inflatable portion of the balloon catheter is positioned at the natural aortic valve position;
(e) inflating the second inflatable portion of the balloon catheter so that the deployable stent device is deployed within the aorta thus anchoring the deployable annular stent and the coupled valve device in position;
(f) inflating the first inflatable portion of the balloon catheter so as to deploy the implantable prosthetic valve device in position at the natural aortic valve position;
(g) deflating the first and second inflatable portions of the balloon catheter; and
(h) retracting the balloon catheter and removing it from the patient's body.
a and 18b illustrate an accessory crimping device that is adapted to crimp a valve device in the operating theater as part of the implantation procedure. The crimping device 330 comprises several adjustable plates that resemble a typical SLR camera variable restrictor. It is comprised of simultaneously movable plates 332 each provided with a blade 334, that are equally dispersed in a radial symmetry but each plate moves along a line passing off an opening in the center, all plates equidistant from that center opening 336. Initially (see
a depicts a crimping method for the support stent of the valve prosthesis device of the present invention, whereby stent 340 is crimped, that is, compressed or curled. In
a and 20b depict a valve made of a simple tube mounted to a stent 352. During systole period the tube is fully open and during diastole period the tube collapses according to the mounting geometry 357 and achieves sealing.
a to 23c depict a new method of manufacturing an artificial or biological crimpable valve device. A piece of fabric material 370 (
Reference is now made to
b is a detailed cross-sectional view of one of the support beam 422. Two pericardial leaflets 430 are inserted through a U-shaped, or forked holder 428 that compresses and restricts the leaflets in the U-shaped profile. Leaflets 430 are folded to both sides of the support beam 422. When holder 428 is compressed toward the support beam 422, leaflets 430 are caught in-between holder 428 and support beam 422 so that the leaflets are kept in place.
It is noted again that the entire valve structure is adapted to be radially crimped and radially expanded. This feature imparts the valve with the ability and ease to navigate through narrow passages in the vasculature during positioning of the device. After final positioning of the valve, the valve is deployed. This is made possible by the provision of a collapsible support frame structure. However, the length of the attaching means (the height of the valve) remains at all times constant; thus suitable for serving as the pliable valve assembly's anchorage. The leaflets are attached to the support frame at the attaching means, and due to their constant length there is no need for slack material as these attachment points that remain at constant distances regardless of the position of the valve assembly (crimped or deployed). This is an important feature for this means that the manufacturer of the valve device can make sure the valve assembly is secured and fastened to the support frame at all times. In prior art implantable valve devices, the entire support structure changes its dimensions from its initial first crimped position to final deployed position and this means that in the attachment of the valve leaflets to the support structure one must take into consideration these dimension changes and leave slack material so that upon deployment of the device, the valve assembly does not tear or deform. In the valve device of the present invention there is no relative movement between the valve leaflets and the support beams (along the longitudinal central axis of the device). As a result, the valve device of the present invention acquires greater durability and is capable of withstanding the harsh conditions prevailing within the vasculature and especially the millions of cycles of stress applied by the blood pressure.
The fixed attachment of the valve leaflets to the support frame in the valve assembly device of the present invention renders it greater stability, enhanced safety, better sealing and consequently longer lifespan. The novel design of the valve device of the present invention renders it longitudinal strength and rigidity whereas its collapsible support structure renders it radial flexibility.
a to 25d illustrate an implantable prosthetic valve in accordance with another preferred embodiment of the present invention.
a to 26c illustrate a tricuspid valve in accordance with yet another preferred embodiment of the present invention, provided with a self-expandable frame.
The embodiments that will be shown herein after are optional configurations of attachment between the leaflets and the support frame.
a and 29b illustrate an isometric view and an upper cross sectional view, respectively, of an attachment assembly of a valve's frame to leaflets in accordance with a preferred embodiment of the present invention. The attachment is similar in principle to the attachment shown in
a to 30c illustrate an isometric view, a cross-sectional view and a flatten view, respectively, of an attachment assembly of a valves frame to leaflets in accordance with another preferred embodiment of the present invention. Using the method demonstrated in
a and 31b illustrate an exploded view and an isometric view, respectively, of a commissural attachment in accordance with a preferred embodiment of the present invention depicting the attachment technique. A method of assembling pericardial leaflets 430 to a frame 420 is demonstrated. A rigid bar 476 provided with integral protrusions 478 is inserted through bores 479 that are pre-cut in pericardial leaflets 430. Integral protrusions 478 pass through a sheet of preferably PET (braided polyester) fabric 475, and finally through bores 442 that are provided in longitudinal bar 440 (the attachment means) of frame 420. After the assembling of the parts, as shown in
a to 32c illustrate an isometric view of an attachment between leaflets and the frame in accordance with yet another preferred embodiment of the present invention. An optional method of attachment is demonstrated, in which a pericardium leaflet 430 and bars 480 are sutured in an area as far as possible from the working area of the leaflets. The pericardium is first sutured using a suture 484 to bar 480 as seen in
a to 33d illustrate different views of portions of an attachment between a pericardium and a frame in accordance with yet another preferred embodiment of the present invention, demonstrating another method of attachment in accordance with the preferred embodiment. A connecting member 490 (shown in a deployed position in
a to 34c illustrate an isometric view of an attachment between a pericardium and a valve in accordance with yet another preferred embodiment of the present invention demonstrating another method of attachment. In
Reference is now made to
a and 35b focus on the connection of the commissural assembly to frame's protrusion 509, which is an integral part of the frame and is the basis for the commissural attachment. This example shows the use of four rigid longitudinal bars 503 connected by a suture 502.
a to 37c illustrate a commissural assembly in accordance with another preferred embodiment of the present invention, where the connecting bar functions as a flexible support and has integral attachment means to the frame.
a to 38g illustrate isometric views of flexible commissural supports and the method of attaching them to a pericardium and a frame a valve in accordance with preferred embodiments of the present invention.
d illustrates an isometric view of a flexible commissural support in accordance with yet another preferred embodiment of the present invention, demonstrating the attachment of the pericardium to the support.
a illustrates a technique of commissural assembly using a shaped compressing member 511. The compression member 511 holds pericardial leaflets 500 firmly while pressing it in the pivot points 513. A radial edge 514 is made in order to protect the pericardium from abrasion. The whole assembly is held tightly inside the compressing member 516. The commissural assembly is connected to the frame by protrusion member 518, which fit bores in the frames bar 480.
a to 40c illustrate an isometric view of a bicuspid valve mounted on a frame in accordance with yet another preferred embodiment of the present invention.
Reference is now made to
Reference is now made to
Reference is now made to
Reference is now made to
a to 45d illustrate an isometric view of an implantable prosthetic valve in accordance with yet another preferred embodiment of the present invention, having leaflets sutured to a pre-shaped PET tube and optional leaflet-tube attachments in details. A novel technique of mounting pericardial leaflets 580 to a pre shaped PET tube 585 is shown. The tube is shaped so as to have a folding 586 with substantially sinusoid pattern 586 that is similar to the optimal connection line of valve leaflets in the natural valve. This shape allows the pericardial leaflets to be sutured to the interior of the PET tube. The preferred suturing techniques are shown in the cross sectional views of PET tubes in
Reference is now made to
a to 47c illustrate a partial cross-sectional side view of an inflating balloon in accordance with a preferred embodiment of the present invention. The balloon is a part of an implantable prosthetic valve delivery system.
a and 48b illustrate a partial cross-sectional side view and an upper cross sectional view of an inflating balloon in accordance with another preferred embodiment of the present invention. The inflating balloon comprises of a central inflating balloon 620 and three protection sheets 622. In the lateral cross-section shown in
The preferred embodiments representing an implantable prosthetic valve in accordance with the present invention are relatively easy to manufacture as they are generally flat throughout most of the production process and only at the final stage of mounting the other elements of the valve assembly on the support frame, a three dimensional form is established.
A typical size of an aortic prosthetic valve is from about 19 to about 25 mm in diameter. A maximal size of a catheter inserted into the femoral artery should be no more than 8 mm in diameter. The present invention introduces a device, which has the ability to change its diameter from about 4 mm to about 25 mm. Artificial valves are not new; however, artificial valves in accordance with the present invention posses the ability to change shape and size for the purpose of delivery and as such are novel. These newly designed valves require new manufacturing methods and technical inventions and improvements, some of which were described herein.
As mentioned earlier, the material of which the valve is made from can be either biological or artificial. In any case new technologies are needed to create such a valve.
To attach the valve to the body, the blood vessels determine the size during delivery, and the requirements for it to work efficiently, there is a need to mount it on a collapsible construction which can be crimped to a small size, be expanded to a larger size, and be strong enough to act as a support for the valve function. This construction, which is in somewhat similar to a large “stent”, can be made of different materials such as Nitinol, biocompatible stainless steel, polymeric material or a combination of all. Special requirement for the stent are a subject of some of the embodiments discussed herein.
The mounting of the valve onto a collapsible stent is a new field of problems. New solutions to this problem are described herein.
Another major aspect of the design of the valve of the present invention is the attachment to the body.
In the traditional procedure the valve is sutured in place by a complicated suturing procedure. In the case of the percutaneous procedure there is no direct access to the implantation site therefore different attachment techniques are needed.
Another new problem that is dealt herein is the delivery procedure, which is new and unique. Positioning of the device in the body in an accurate location and orientation requires special marking and measuring methods of the device and surgical site as was disclosed herein.
Artificial polymer valves require special treatment and special conditions when kept on a shelf, as well as a special sterilization procedure. One of the consequences of the shelf treatment is the need to crimp the valve during the implantation procedure. A series of devices and inventions to allow the crimping procedure are disclosed herein.
It should be clear that the description of the embodiments and attached Figures set forth in this specification serves only for a better understanding of the invention, without limiting its scope as covered by the following claims.
It should also be clear that a person skilled in the art, after reading the present specification could make adjustments or amendments to the attached Figures and above described embodiments that would still be covered by the following claims.
This application is a continuation of co-pending U.S. patent application Ser. No. 13/168,016, filed Jun. 24, 2011, which is a continuation of U.S. patent application Ser. No. 11/692,889, filed Mar. 28, 2007, now abandoned, which is a continuation of U.S. patent application Ser. No. 10/637,882, filed Aug. 8, 2003, now U.S. Pat. No. 7,510,575, which is a divisional of U.S. patent application Ser. No. 10/270,252, filed Oct. 11, 2002, now U.S. Pat. No. 6,730,118, which is a continuation-in-part of U.S. patent application Ser. No. 09/975,750, filed Oct. 11, 2001, now U.S. Pat. No. 6,893,460.
| Number | Name | Date | Kind |
|---|---|---|---|
| 5992000 | Humphrey et al. | Nov 1999 | A |
| 6454799 | Schreck | Sep 2002 | B1 |
| 20010021872 | Bailey et al. | Sep 2001 | A1 |
| Number | Date | Country | |
|---|---|---|---|
| 20120277856 A1 | Nov 2012 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 10270252 | Oct 2002 | US |
| Child | 10637882 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 13168016 | Jun 2011 | US |
| Child | 13529909 | US | |
| Parent | 11692889 | Mar 2007 | US |
| Child | 13168016 | US | |
| Parent | 10637882 | Aug 2003 | US |
| Child | 11692889 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 09975750 | Oct 2001 | US |
| Child | 10270252 | US |
