US 3538514 A
Description (OCR text may contain errors)
Nov. 10, 1970 G.SCHIMERT EIAL 3,538,514
ARTIFICIAL HEART VALVE Filed Dec. 23, 1968 INVENTORS GEORGE SCHIMERT TOIVO JOHN BOHM BY 1 ATTORNEYS United States Patent 3,538,514 ARTIFICIAL HEART VALVE George Schirnert, 6963 Old Lake Shore Road, Lakeview, N.Y. 14085, and Toivo John Bohm, 7550 Salt Road,
Clarence Center, NY. 14032 Filed Dec. 23, 1968, Ser. No. 786,086 Int. Cl. A61f 1/22 U.S. Cl. 3--1 Claims ABSTRACT OF THE DISCLOSURE The occluder disc of a prosthetic heart valve is mounted on the valve ring simultaneously to lift away and tilt with respect to the valve ring, giving rise to improved flow characteristics. The occluder has dual, concentric seating portions to form a cushioning chamber as the valve closes, thereby providing quiet operation and minimizing blood damage. Also, the guide posts mounting the occluder intersect such chamber allowing a controlled bleed olf avoiding bounce and additionally forcing blood along the bases of the posts continually to cleanse them and avoid the formation of deposits.
BACKGROUND OF THE INVENTION Surgical techniques have advanced to the point in Which it is rather commonplace to implant a prosthetic valve in the human heart. There are very many types of valves currently available and many of the early problems in connection with the construction and general design of such prosthetic heart valves have now been overcome. However, the problems of noise in operation, formation of deposits which may later break away as thrombi, and damage to the living tissue of the blood remain as problems to some degree or another in connection with prosthetic heart valves.
BRIEF SUMMARY OF THE INVENTION The present invention seeks to overcome the above noted problems in connection with prosthetic heart valves while at the same time achieving excellent flow characteristics, tending to maintain the laminar flow of the blood and in general avoiding turbulence. The present invention accomplishes the objectives intended by utilizing an occluder having notches therein which receive guide posts allowing the occluder to lift away from and tilt with respect to the valve ring seat, thereby providing the excellent flow characteristics. Additionally, the occluder disc seats against the valve ring along concentric lines to provide a blood chamber therebetween so as to cushion the closing effect of the valve resulting in more quiet operation and also minimizing the damage to the blood cells incidental to closing the valve. Additionally, this chamber is used to advantage in order to cause the entrapped blood controllably to bleed off along the lengths of the posts at their bases whereby continually to cleanse them, thus avoiding the formation of deposits and also providing a controlled means for terminating the cushioning effect without causing bouncing of the valve.
BRIEF DESCRIPTION OF THE DRAWING FIGURES FIG. 1 is a perspective view showing the improved valve according to the present invention in open position;
FIG. 2 is a sectional view through a model of the human heart illustrating the relative positioning of the present valve therein;
FIG. 3 is an enlarged plan view of the valve shown in FIG. 1;
FIG. 4 is an enlarged section taken substantially along the plane of section line 44 in FIG. 3 illustrating the chamber and cleansing effect attributable thereto; and
FIG. 5 is a sectional view taken substantially along the plane of section line 5-5 in FIG. 3, showing the valve in fully closed and fully open positions and illustrating the natural flow characteristics attained thereby.
DETAILED DESCRIPTION OF THE INVENTION With reference now more particularly to FIG. 1, the reference character 10 indicates in general a valve ring provided with a suturing collar indicated generally by the reference character 12, the ring and collar being of entirely conventional construction and forming, per se, no part of the present invention. It may be mentioned, however, that the construction shown in FIG. 1 employs a suturing collar adapting the valve device for implantation in the 'mitral position whereas the collar in FIG. 2 is constructed to adapt the valve 'for aortic positioning. The ring 10 is provided with a beveled valve seat 14 with which an occluder disc indicated generally by the reference character 16 cooperates to perform the requisite valve action.
The occluder disc 16 is mounted and retained relative to the valve ring 10 *by a pair of post members 18 and 20 allowing the occluder disc 16 to lift away from and tilt with respect to the valve ring 10 in the manner indicated in full and phantom lines in FIG. 5. The movement or action permitted of the occluder disc 16 by virtue of its mounting through the medium of the posts 18 and 20 is of substantial importance inasmuch as it allows the blood to flow as naturally as possible past the valve assembly without introducing turbulence and in general preserving the laminar flow characteristics which otherwise naturally occur. This effect is shown more particularly in FIG. 2 wherein the valve assembly according to the present invention is implanted as an aortic valve within the heart indicated generally by the reference character 22. As is conventional, the valve assembly is placed in position through a suitable incision 24 made in the aorta 26 and the suturing collar 12 is utilized to suture the valve in the proper position. As is shown, the main flow of blood is as indicated by the arrow 28 from the left ventricle 30 into the aorta substantially without deviation and while retaining the laminar flow characteristics obtained with the normal valve to the substantial exclusion of turbulence. A minor flow occurs behind the valve as indicated by the arrow 32 and this minor flow is controlled, as will hereinafter appear, to obtain certain advantageous results.
As may be seen more clearly in FIG. 5, the occluder disc 16 includes a radially projecting rim or flange 34 and a frusto-conical body portion 36 integral therewith and these portions cooperate with the valve ring seat 14 to define an annual chamber 38, the flange 34 and body portion 36 hearing against the valve seat 14 along concentric lines when the valve assembly is closed. The cushioning chamber 38 serves to prevent the occluder disc 16 from pounding against the valve ring 10, thereby performing two functions. First of all, the valve assembly is extremely quiet in operation and, secondly, the cushioning effect prevents or at least minimizes shearing and damage to the blood cells which might otherwise occur.
A further effect is attained by the cushioning chamber 38 in conjunction with the posts 18 and 20 and the particular manner in which they are mounted on the valve ring 10. This may be seen best in FIG. 4 wherein it will be appreciated that the posts 18 and 20 are secured at their lower ends to the valve seat surface 14 within the confines of the cushioning chamber 38. The occluder disc 16 is provided with notches 40 and 42, as may also be seen in FIG. 3, so that the notches 40 and 42 act as controlled flow bleed passages preventing the complete entrapment of fluid within the cushioning chamber 38 and allowing the valve gently but firmly to close. Additionally, as can be seen in FIG. 4, the closing action of the valve causes the blood which would otherwise be trapped in the cushioning chamber 38 to escape in the fashion indicated by the arrow 44 to scrub along the base of the post 18 and the post 20 so that these critical areas are constantly cleansed to the substantial exclusion of the formation of deposits and the like.
The posts 18 and 20 are raked or curved rearwardly as shown to allow the occluder disc 16 to cock or tilt rearwardly and the notches 40 and 42 are sufiiciently large widthwise with respect to the diameter of the posts 18 and 20 to allow a limited degree of pivotal motion by virtue of this relationship alone, the net effect being to allow the occluder disc 16 completely to lift away from the valve seat 14 and to assume a substantial angle with respect thereto, as may be seen more clearly in FIG. 5, and this natural action allowing the aforementioned minor flow 32 of blood to pass rearwardly and prevent the formation of dead flow pockets or spaces behind the valve. To enhance this minor flow characteristic, the rear edge of the valve is provided with a flattened portion 46 as may be seen in FIGS. 3 and 5 and this portion also provides clearance to prevent jamming of the valve in the open position. The upper or free ends of the posts 18 and 20 are laterally bent as indicated by the reference characters 48 an 50 so as to provide limit stops for the occluder disc 16.
The construction shown, in addition to the advantages noted, has proven to effect negligible wear on the posts 18 and 20, thus assuring long service life from this standpoint. The posts are, at the same time, extremely free from any predisposition to accumulate deposits of any kind which would represent a potentially dangerous condition for the recipient of the valve device. The minor flow charactertistics previously mentioned due to the presence of the flat 46 is extremely effective to maintain the outer surface of the occluder disc free of deposits while, at the same time, allowing for a more natural blood flow.
The present invention, therefore, is well adapted to carry out the objects and attain the ends and advantages mentioned as well as other inherent therein. While the presently illustrative embodiment of the invention is given for the purpose of disclosure, numerous changes in the details of construction and arrangement of parts may be made which will readily suggest themselves to those 4 skilled in the art and which are encompassed within the spirit of the invention and the scope of the appended claims.
1. In a prosthetic heart valve of the type having a valve ring provided with an annular valve seat surface and a suturing collar for securing the valve in place, the improvement comprising:
spaced guide posts secured to and outstanding from said ring, said posts curving away from the longitudinal axis of said valve ring in the same general direction and provided with stop elements at their outer extremities, and an occluder disc provided with spaced notches receiving said posts for both pivotal and sliding movement with respect thereto, whereby the occluder disc may lift and swing away from said valve seat.
2. In the prosthetic heart valve as defined in claim 1 wherein said occluder disc is provided with a flattened portion in its rear edge to controllably bleed fluid past that portion of said disc.
3. In the prosthetic heart valve as defined in claim 1 wherein said occluder disc is provided with concentric bearing surfaces engaging said valve seat in the closed position to define a cushioning chamber therewith.
4. In the prosthetic heart valve as defined in claim 3 wherein said notches intersect said cushioning chamber controllably to bleed fluid therefrom along said posts.
5. In the prosthetic heart valve as defined in claim 4 wherein said posts intersect said valve seat within the confines of said chamber.
References Cited UNITED STATES PATENTS 1,454,207 5/1923 Bemis l37527 XR 2,045,518 6/1936 Chatfield 137527 XR 3,374,489 3/1968 Diaz 3-l 3,438,394 4/1969 Nakib 31 XR 3,445,863 5/1969 Wada 31 RICHARD A. GAUDET, Primary Examiner R. L. FRINKS, Assistant Examiner U.S. Cl. X.R.