CA1066853A - Heart valve with arcuate occluder - Google Patents
Heart valve with arcuate occluderInfo
- Publication number
- CA1066853A CA1066853A CA259,375A CA259375A CA1066853A CA 1066853 A CA1066853 A CA 1066853A CA 259375 A CA259375 A CA 259375A CA 1066853 A CA1066853 A CA 1066853A
- Authority
- CA
- Canada
- Prior art keywords
- vane
- valve
- occluder
- curvature
- arc
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
- A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
- A61F2/02—Prostheses implantable into the body
- A61F2/24—Heart valves ; Vascular valves, e.g. venous valves; Heart implants, e.g. passive devices for improving the function of the native valve or the heart muscle; Transmyocardial revascularisation [TMR] devices; Valves implantable in the body
- A61F2/2403—Heart valves ; Vascular valves, e.g. venous valves; Heart implants, e.g. passive devices for improving the function of the native valve or the heart muscle; Transmyocardial revascularisation [TMR] devices; Valves implantable in the body with pivoting rigid closure members
- A61F2/2406—Heart valves ; Vascular valves, e.g. venous valves; Heart implants, e.g. passive devices for improving the function of the native valve or the heart muscle; Transmyocardial revascularisation [TMR] devices; Valves implantable in the body with pivoting rigid closure members without fixed axis
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T137/00—Fluid handling
- Y10T137/7722—Line condition change responsive valves
- Y10T137/7837—Direct response valves [i.e., check valve type]
- Y10T137/7898—Pivoted valves
- Y10T137/7903—Weight biased
Abstract
HEART VALVE WITH ARCUATE OCCLUDER
Abstract A convexo-concave, saucer-like heart valve vane is float-ingly supported in a valve ring between a vane closing support rod, which engages the edge of a concentric recess on the arcuate convex side of the vane, and a vane closing support rod which engages the arcuate concave side of the vane. In its open position, the limiting portion of the convex distal surface of the vane is nearly aligned with the blood stream to maximize the blood flow through the portion of the valve defined by said portion and the adjacent portion of the ring.
Abstract A convexo-concave, saucer-like heart valve vane is float-ingly supported in a valve ring between a vane closing support rod, which engages the edge of a concentric recess on the arcuate convex side of the vane, and a vane closing support rod which engages the arcuate concave side of the vane. In its open position, the limiting portion of the convex distal surface of the vane is nearly aligned with the blood stream to maximize the blood flow through the portion of the valve defined by said portion and the adjacent portion of the ring.
Description
Specification Beginning in about 1960, the use of heart valve prosthesis amerged rom a period oE experimentatlon into a period of practical, surgical application. The medical literature in the field of cardiovascular surgery includes numerous surgical procedures and techniques for implanting heart valve prostheses and many heart valve prostheses are described. Reference is made to this body of literature respecting the medical aspects 20 of heart valve prosthesis implantation and usage, specific reference being made to the publications of Professor Viking :
0. Bjork, in the Scandinavian Journal of Thoracic and Cardio-vascular Surgery.
~...
-, In U.S. Patent 3,824,629-Shiley there is d.isclosed a heart ~, ~ valve prosthesis having a vane which is eccentrically supported :~.;
~' by structure extenting inwardly from the surrounding valve ring ' so as to floatingly contain the vane during opening and closing ~"~`! movement in response to the pumping action of the heart. This . ~ .
application relates to an improvement in such a valve.
j .,, ';i .
.
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-, .. ... ~ . . ....... . . . .. .. ..... . .. . .
` ~ 1066853 1 The earlier Shiley valve has been highly successful, .. ` % providing excellent results and becoming welL ~ccepted în the medical profession. Such valves have had very little thrombus . formation which has bean a problem with many of the prior art : 5 va}ves. Nevertheless, there exists the poten~ial in isolated ~`: 6 cases for some thrombus ormation even with the valve of tha above patenk. In such isolated cases, thrombus is most likely to occur in areas o~ the valve which are washed less thoroughly 9 by the blood than the other areas. It is, of course, desirable, -- 10 ~if possible, to further reduce the potential for thrombus formation. In the heart valve disclosed in the above mentioned 12 Shiley patent, :the vane divides the ori~ice through the valve ~ ..
-~ 13 ring into two flow areas of unequal siæe because of the eccentric~
.~ ~ 14 mounting of the vane. The vane ~tilts in the range of 50 to 80 from a closed position parallel to the plane of.the valve ring~
t~ 16 ~into:the fully open position. When in this open position~ on~ .
lq the proximal side of the valve the leading edge o the vane :
18 is oriented~at~approximately this same opening angle since~the .
19 vane has a relativ~l~ thiin cross-section, which tapers towards .
20 ¦ the~edge uniformly on~both sides. Consequently,~ the leadlng 21 ~dge of ~he vane tends ~o direct a larger proportion of the:blood 22 ¦ towards the larger area ~hrough the orifice khan the ratio ¦ be~ween the large an~d small areas of the orifice would indicate!
24 ~That is, if the ~smaller area through the va~e orifice constitutes 25 :25~t~ of the: total area, the smaLler ~rea does not necessa~ily .
26 ¦ receive 25vh oE the blood flow. .Blood flow through the ~alve , ~ 27~ ¦ could be ~increas~ed~by opening the vane more fully; however~ this .28 ¦ may ~ot~be advantageous because of the additional travel time:
2g: ¦ required ~or:the vanel to open and~close. :
30~ ~ ~
31. ~ :
32 ~ : ~ . -: ' ' - ' , ~ ,:
: __ ,, . .
1066~153 ~ In accordance with the present lnven~ion, ttle percentage : 2 of blood flow through the smaller are,a of the orifice at a given flow rate t~rough the valve has been increased by changing the configuration o~ the vane without increasing the pressure . 5 gradient across the valve. In particular, the vane is formed 6 with a saucer- like con:~iguration having an arcuate convex surface on one side and an arcuate concave surface on the other, . 8 maintaining a very thin profile to obtain rapid valve operation .
.: 9 and providing smoothly curved surfaces and lower pressure gradient across thei valve. As in the earlier Shiley patent : ll mentioned above, the vane is eccentrically mountad so that the ~:- 12 vane in open position creates flow areas through the valve`: 13 of une~ual si2e . However, the percentage o ~low through the ;
1~ smaller orifice area has been increased by arranging the vane : 15 so that en~ra~ce to the smaller orifice area is increased~ The 16 vane is oriented so ~hat the convex sur~ace deflnes the smaller 17 orifice area in coopera~ion wi~h the aajacen~ portion o~ the .-. 18 val~e ring. The tangent to the arcuate convex surace on the : 19 leading edge of the vanb ;s substantiaily aligned with the blood .
Z0 1aw when the vane is in- its ~ully open position, with the result .
21 that small~er ori~ice ar.ea: is fully open to fluid ~low and the 22 vane di~idss the flow with a m}nimum of turbulence. As mentioned, : 23 the pressur2 gradient across the valve remains at a low level. . :
4 In the preferred arrangement, the vane ig supported by a .
`,; ~ 25 pair of support rods extending inwardly from the surrounding .`5. 26 valve ring. A vane opcning support rod provides a surace :.3 ~ ~ e~gaging a shallow central recess in the convex side of the vane 28 formin~ an ~symmetri~ knuckle-like joint to enable the vane to ~ g: ~ilt around this knuckle during ~s opening operation. A vane '~5~ 30 . . .
~; 31 .
1 .
,~32 . . .
. . . -3-. , .
,.. . , ~ . : . ~
~6~353 closing suppo~t rad ~s loc~ted on the conc~ye ~ide o;E the ~ane to ~orm a changing rocker~like contact l~ne ~or the vane during its closing operation, Because oE the con~rexo-~concave conEigur-ation of the vane, it is free to move slightly away fro~ the vane orifice in the open position which further minimizes the likelihood of thrombus formation between the vane and the orifice.
The central circular recess in the convex s,ide of the vane enables the vane to rotate about a central axis of the vane in its loosely captive arrangement between the two support rods.
This provides improved washing of the vane and evenness of wear.
The combined arcuate proximal and distal surface arrangement ` maximizes fluid flow through the smaller area of the val~e while ., . ~
i maintaining a low pressure drop across the valve.
.... .. .
The arrangement described wherein the upper and lower surfaces of the valve occluder are arcuately configured provides `~ a particularly low pressure gradient across the valve as compared - for example~ with a valvè in which the distal surface is in the ,. . .
configuratio~ of a right frustocone, ha~ing a depression in the top center of the frustum (or the equivalent, a circular depres-; 20 sion adiacent the top of the conical surface) and the proximal `
?,' side of the occluder is configured as the inside of a right --.~. ::,.
frustocone: i.e., having an inwardly slanting circular sidewall and a flat top.
4~
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d ,;
~ .
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6~3S3 ~ Ihe present~invention o~titutes a signiEic~ut.i~px~nt over the aforementioned valve having frustQconi~al distal and proximal sulidce configurations by su~stantlally i~mproved flow pattern ~ and decreased pressure gradient, thus making the present invention suitable for use in patients whose cardiac pumping capacity has been i~paired by disease, d~nage or otherwise in : which considerable additional risk would be inherent in the use ~ of frustoconically configured valYe occluder.
. :
In accordance with one broad aspect, the invention relates to a heart valve prosthesis having a valve ring, means for securing the valve ring in the place of a natural heart ~ :
valve, a free floating, rotatable, discoid valve occluder and means for mounting the occluder for repetitive movement between the open and closed positions, the improvement wherein: the -valve occluder is a vane having radial symmetry about a center axis perpendicular to the general plane of the vane, and . :
having a generally arcuate convex distal surface with a distal ..
:,, ~ depression surrounding the center o the vane and having a ~ :
.. . .
-1 20 concave proximal surface which is generally arcuate with a large .i, arc o~ curvature to define a thin disc with a relatively .~ smooth proximal--surface; and the mounting means comprising opening support structure extending on the distal side of the ;: occluder from the valve ring to the depression in the vane, the ,~ inner portion of ~he opening support structure-extending into ~ the depression to engage therein to control the opening movement :
''d; ~ ' of the occluder and to provide a knuckle-like joint between the 3:
opening support structure and the occluder during opening; and a closing support structure extending from the ring into the arcuate concavity of the proximal surface to provide a rocker~
ke contact support surface for the occluder during closure, a~
~ _ ~6~C~3 the contact between the support surface and the occluder moving toward the center during closure said mounting-means permitting ~ree rotation of said occluder about its center as the occluder opens and closes.
In accordance with another aspect, the invention relates to a heart valve prosthesis which comprises a val~e ~ .
ring having a passage for blood therethrough; means for securing the valve ring in the place of a natural heart valve;
a valve occluder in the form of a discoid vane having radial symmetry about a center axis perpendicular to the general plane .:
of the valve occluder, and having an arcuately curved concave proximal side with a single laxge arc of curvature to define a thin disc with a relatively smooth proximal surface and a ~.;
distal side which is generally arcuately curved and convex and has a depression therein; distal opening support structure . :
extending from the valve ring înto the passage and then in the .~
proximal direction into the depression in the distal side of the ~ -occluder vane to form therewith a knuckle-like joint about :: -which the vane moves as it opens in response to pressure applied in the distal direction; and proximal closing support structure extending from the ualve ring into the passage and in the distal direction in curved configuration into the arcuate concavity of the vane to provide a rocker-like support ~or the ~ane as the vane closes in response to pressure applied in the proximal direction, the closing support being so con~i~ured in '!'. ,.,.'' relation to the arcuate concave sur~ace that thb contact area .1: .
between the closing support and the vane moves toward the center of the vane during closure thereby reducing the eccentr.~c ~ ; . . closing force as the valve &luses; the opening and clos.ing '! 30 : support structures cooperatively defining the maxim~ open ~ osition of the vane such that blood flows over the arcuate ., .
~ 5a s3 convex distal surface and the arcuate concave pxoximal surEace when the valve is opened b~ the pressure of blood applied in the distal direction; the opening and closing support structures cooperating with the occluder to permit the occluder : to rotate about its center axis as it opens and closes.
For a more thorough understanding of the heart valve prosthesis of this invention reference may be had to the following detailed descrlption and drawings wherein;
-~ Fig. 1 is a diagrammatic sectional view of a heart with the prosthesis of this in~ention inserted in place of the natural mitral and aortic heart valves; . : :
Fig. 2 is a top perspective view of tha heart yal~e prosthesis constructed in accordance with this invention;
Fig. 3 is a top plan view of the prosthesis of Fig. 2, with the suture ring omitted;
.~ Fig. 4 is a sectional view through the prosthesis of ,. Fig. 3 on lines 4-4;
.~ Fig. 5 is a sectional view of the prosthesis o Fig. 3 . ~ .
.~ on lines 5-5; and . . .
20: Fig. 6 is a sectional view of the prosthesis similar ~, to Fig. 4 but showing the valve vane in an open position.
. ~ .
~` ~ Fig. 7 is a top perspective view of an alternative .' construction.
1i; Although the heart valve prosthesis of this invention .
,;, ~; lS particularly adapted for use as an aortiic or mitral valve, as shown diagrammatically in Fig. 1, the prostheses 10 and 10 may be ;"
~ 30 ~:
) : -:i -5b-! , , ~. :.,, ' "- ' 1066~1~3 l I made in various sizes for use either as an aortLc, mitral or
0. Bjork, in the Scandinavian Journal of Thoracic and Cardio-vascular Surgery.
~...
-, In U.S. Patent 3,824,629-Shiley there is d.isclosed a heart ~, ~ valve prosthesis having a vane which is eccentrically supported :~.;
~' by structure extenting inwardly from the surrounding valve ring ' so as to floatingly contain the vane during opening and closing ~"~`! movement in response to the pumping action of the heart. This . ~ .
application relates to an improvement in such a valve.
j .,, ';i .
.
J~
-, .. ... ~ . . ....... . . . .. .. ..... . .. . .
` ~ 1066853 1 The earlier Shiley valve has been highly successful, .. ` % providing excellent results and becoming welL ~ccepted în the medical profession. Such valves have had very little thrombus . formation which has bean a problem with many of the prior art : 5 va}ves. Nevertheless, there exists the poten~ial in isolated ~`: 6 cases for some thrombus ormation even with the valve of tha above patenk. In such isolated cases, thrombus is most likely to occur in areas o~ the valve which are washed less thoroughly 9 by the blood than the other areas. It is, of course, desirable, -- 10 ~if possible, to further reduce the potential for thrombus formation. In the heart valve disclosed in the above mentioned 12 Shiley patent, :the vane divides the ori~ice through the valve ~ ..
-~ 13 ring into two flow areas of unequal siæe because of the eccentric~
.~ ~ 14 mounting of the vane. The vane ~tilts in the range of 50 to 80 from a closed position parallel to the plane of.the valve ring~
t~ 16 ~into:the fully open position. When in this open position~ on~ .
lq the proximal side of the valve the leading edge o the vane :
18 is oriented~at~approximately this same opening angle since~the .
19 vane has a relativ~l~ thiin cross-section, which tapers towards .
20 ¦ the~edge uniformly on~both sides. Consequently,~ the leadlng 21 ~dge of ~he vane tends ~o direct a larger proportion of the:blood 22 ¦ towards the larger area ~hrough the orifice khan the ratio ¦ be~ween the large an~d small areas of the orifice would indicate!
24 ~That is, if the ~smaller area through the va~e orifice constitutes 25 :25~t~ of the: total area, the smaLler ~rea does not necessa~ily .
26 ¦ receive 25vh oE the blood flow. .Blood flow through the ~alve , ~ 27~ ¦ could be ~increas~ed~by opening the vane more fully; however~ this .28 ¦ may ~ot~be advantageous because of the additional travel time:
2g: ¦ required ~or:the vanel to open and~close. :
30~ ~ ~
31. ~ :
32 ~ : ~ . -: ' ' - ' , ~ ,:
: __ ,, . .
1066~153 ~ In accordance with the present lnven~ion, ttle percentage : 2 of blood flow through the smaller are,a of the orifice at a given flow rate t~rough the valve has been increased by changing the configuration o~ the vane without increasing the pressure . 5 gradient across the valve. In particular, the vane is formed 6 with a saucer- like con:~iguration having an arcuate convex surface on one side and an arcuate concave surface on the other, . 8 maintaining a very thin profile to obtain rapid valve operation .
.: 9 and providing smoothly curved surfaces and lower pressure gradient across thei valve. As in the earlier Shiley patent : ll mentioned above, the vane is eccentrically mountad so that the ~:- 12 vane in open position creates flow areas through the valve`: 13 of une~ual si2e . However, the percentage o ~low through the ;
1~ smaller orifice area has been increased by arranging the vane : 15 so that en~ra~ce to the smaller orifice area is increased~ The 16 vane is oriented so ~hat the convex sur~ace deflnes the smaller 17 orifice area in coopera~ion wi~h the aajacen~ portion o~ the .-. 18 val~e ring. The tangent to the arcuate convex surace on the : 19 leading edge of the vanb ;s substantiaily aligned with the blood .
Z0 1aw when the vane is in- its ~ully open position, with the result .
21 that small~er ori~ice ar.ea: is fully open to fluid ~low and the 22 vane di~idss the flow with a m}nimum of turbulence. As mentioned, : 23 the pressur2 gradient across the valve remains at a low level. . :
4 In the preferred arrangement, the vane ig supported by a .
`,; ~ 25 pair of support rods extending inwardly from the surrounding .`5. 26 valve ring. A vane opcning support rod provides a surace :.3 ~ ~ e~gaging a shallow central recess in the convex side of the vane 28 formin~ an ~symmetri~ knuckle-like joint to enable the vane to ~ g: ~ilt around this knuckle during ~s opening operation. A vane '~5~ 30 . . .
~; 31 .
1 .
,~32 . . .
. . . -3-. , .
,.. . , ~ . : . ~
~6~353 closing suppo~t rad ~s loc~ted on the conc~ye ~ide o;E the ~ane to ~orm a changing rocker~like contact l~ne ~or the vane during its closing operation, Because oE the con~rexo-~concave conEigur-ation of the vane, it is free to move slightly away fro~ the vane orifice in the open position which further minimizes the likelihood of thrombus formation between the vane and the orifice.
The central circular recess in the convex s,ide of the vane enables the vane to rotate about a central axis of the vane in its loosely captive arrangement between the two support rods.
This provides improved washing of the vane and evenness of wear.
The combined arcuate proximal and distal surface arrangement ` maximizes fluid flow through the smaller area of the val~e while ., . ~
i maintaining a low pressure drop across the valve.
.... .. .
The arrangement described wherein the upper and lower surfaces of the valve occluder are arcuately configured provides `~ a particularly low pressure gradient across the valve as compared - for example~ with a valvè in which the distal surface is in the ,. . .
configuratio~ of a right frustocone, ha~ing a depression in the top center of the frustum (or the equivalent, a circular depres-; 20 sion adiacent the top of the conical surface) and the proximal `
?,' side of the occluder is configured as the inside of a right --.~. ::,.
frustocone: i.e., having an inwardly slanting circular sidewall and a flat top.
4~
S~ `
; ' : . ' j: " :
d ,;
~ .
~'~
6~3S3 ~ Ihe present~invention o~titutes a signiEic~ut.i~px~nt over the aforementioned valve having frustQconi~al distal and proximal sulidce configurations by su~stantlally i~mproved flow pattern ~ and decreased pressure gradient, thus making the present invention suitable for use in patients whose cardiac pumping capacity has been i~paired by disease, d~nage or otherwise in : which considerable additional risk would be inherent in the use ~ of frustoconically configured valYe occluder.
. :
In accordance with one broad aspect, the invention relates to a heart valve prosthesis having a valve ring, means for securing the valve ring in the place of a natural heart ~ :
valve, a free floating, rotatable, discoid valve occluder and means for mounting the occluder for repetitive movement between the open and closed positions, the improvement wherein: the -valve occluder is a vane having radial symmetry about a center axis perpendicular to the general plane of the vane, and . :
having a generally arcuate convex distal surface with a distal ..
:,, ~ depression surrounding the center o the vane and having a ~ :
.. . .
-1 20 concave proximal surface which is generally arcuate with a large .i, arc o~ curvature to define a thin disc with a relatively .~ smooth proximal--surface; and the mounting means comprising opening support structure extending on the distal side of the ;: occluder from the valve ring to the depression in the vane, the ,~ inner portion of ~he opening support structure-extending into ~ the depression to engage therein to control the opening movement :
''d; ~ ' of the occluder and to provide a knuckle-like joint between the 3:
opening support structure and the occluder during opening; and a closing support structure extending from the ring into the arcuate concavity of the proximal surface to provide a rocker~
ke contact support surface for the occluder during closure, a~
~ _ ~6~C~3 the contact between the support surface and the occluder moving toward the center during closure said mounting-means permitting ~ree rotation of said occluder about its center as the occluder opens and closes.
In accordance with another aspect, the invention relates to a heart valve prosthesis which comprises a val~e ~ .
ring having a passage for blood therethrough; means for securing the valve ring in the place of a natural heart valve;
a valve occluder in the form of a discoid vane having radial symmetry about a center axis perpendicular to the general plane .:
of the valve occluder, and having an arcuately curved concave proximal side with a single laxge arc of curvature to define a thin disc with a relatively smooth proximal surface and a ~.;
distal side which is generally arcuately curved and convex and has a depression therein; distal opening support structure . :
extending from the valve ring înto the passage and then in the .~
proximal direction into the depression in the distal side of the ~ -occluder vane to form therewith a knuckle-like joint about :: -which the vane moves as it opens in response to pressure applied in the distal direction; and proximal closing support structure extending from the ualve ring into the passage and in the distal direction in curved configuration into the arcuate concavity of the vane to provide a rocker-like support ~or the ~ane as the vane closes in response to pressure applied in the proximal direction, the closing support being so con~i~ured in '!'. ,.,.'' relation to the arcuate concave sur~ace that thb contact area .1: .
between the closing support and the vane moves toward the center of the vane during closure thereby reducing the eccentr.~c ~ ; . . closing force as the valve &luses; the opening and clos.ing '! 30 : support structures cooperatively defining the maxim~ open ~ osition of the vane such that blood flows over the arcuate ., .
~ 5a s3 convex distal surface and the arcuate concave pxoximal surEace when the valve is opened b~ the pressure of blood applied in the distal direction; the opening and closing support structures cooperating with the occluder to permit the occluder : to rotate about its center axis as it opens and closes.
For a more thorough understanding of the heart valve prosthesis of this invention reference may be had to the following detailed descrlption and drawings wherein;
-~ Fig. 1 is a diagrammatic sectional view of a heart with the prosthesis of this in~ention inserted in place of the natural mitral and aortic heart valves; . : :
Fig. 2 is a top perspective view of tha heart yal~e prosthesis constructed in accordance with this invention;
Fig. 3 is a top plan view of the prosthesis of Fig. 2, with the suture ring omitted;
.~ Fig. 4 is a sectional view through the prosthesis of ,. Fig. 3 on lines 4-4;
.~ Fig. 5 is a sectional view of the prosthesis o Fig. 3 . ~ .
.~ on lines 5-5; and . . .
20: Fig. 6 is a sectional view of the prosthesis similar ~, to Fig. 4 but showing the valve vane in an open position.
. ~ .
~` ~ Fig. 7 is a top perspective view of an alternative .' construction.
1i; Although the heart valve prosthesis of this invention .
,;, ~; lS particularly adapted for use as an aortiic or mitral valve, as shown diagrammatically in Fig. 1, the prostheses 10 and 10 may be ;"
~ 30 ~:
) : -:i -5b-! , , ~. :.,, ' "- ' 1066~1~3 l I made in various sizes for use either as an aortLc, mitral or
2 ¦ tricuspid valve replacement. The aortic valve prosthesis lO
3 ¦ is mounted in the aortic artery 12 at the natural valve ring
4 1 14 intermediate the aorta 12 and the lef~ ventricle 16. The 51 mitral valve prosthesis lO' is mounted in the left ventrîcal 16 on the muscle tissue 18 o~ the natural valve ring intermediate 71 the le~t ventricle and the left atrium 20. For purpose of .
8 ¦ illustrating the prosthesis, it will be discussed primarily as 9 ¦ an aortic valve replacement.
10 ¦ As shown in Figs . 2, 3 and 4, the structure o the prosthesis 11 I 10 in~ludes a metallic valve ring 22 having an ~nn~r wall.which 12 I de:Eines a valve orifice through which the blood fLows as ~ .
13 I controlled~by a movable valve occluder in the form of a discoid 14 ¦ vane 24. (The vane is not truly a disc, although that term is 1~ ¦.loosely applied to the vane, and the term lldiscoid~ is not 16 ¦ used in any technical sense but is selected merely to suggest 17 ¦ a body which is roundg has an overall thickness less than ~he 18 ¦ diame~er and has a comple~ configuration which is nu~ easily lg~ described except by function and on a portion by portio~ basis.
An~ body which is 50 conrigured as to function in the manner ~l described hereinafter may be regarded as disco;dO) A vane 22 opening support rod 26 and a vane closing support rod 28 have 23 their ends attached~to the valve ring 22 by welding or other 24: suitable means to support the vane for movement within the valve 25 ring 22. Suitable means, ~such as suture ring 23, is secured .
2~ about the ~alve ring for connecting the valve to ~he heart or 27 aortic tissue. One such arrangement is described in ~he above .
28 mentioned ShiLey patent. . ~ .
29 From Fig. ~, it may be seen that the valve vane 24 has a conve~o-concave, saucer-like con~iguration, with the convex . ~ -6- . .
~,` . : . .
~ 10668S3 1 surface 38 having a concentri.c recess ~4 which cre~es an annular 2 van~ portion 36 and a thinner central portion 37. The diska ~ surace 38 of the ~ane 24 has a convex curvat-lre formed on a 4 radius o~ curvature which in a preferred form of the inven~ion is about equal to t~le diameter of the varle 24. The proximal sur~ace 6 40 of ~he vane has a concave curva~ure about a radius of curvature 7 of which in a preferred form of the irlvention is generally in 8 the range of two or three times the radius of curyature of the 9 distal convex surface 38.
The peripheraledge 42 of the vane 24 is ro~mded to lie, 11 in the closed position, adjacent to and, in the pre~erred ~orm, 12 spaced slightly from the inner surface 23 o~ the valve ring 22 ~ 13 which forms:the ori~ice through which the blood flows. In a :. . preferred form of the invention, the ~hickness of ~he edge 42 .
. 15 where the edge curvature starts is greater than the thickne~ss .
~` ~ 16 of the vane cen~ral portion 37. This indicates the ligh~ .
17 weight, low profile of the vane. The ring 22 has the shape of 18 a toroidal sectian with the inner surace being smoothly rounded 19 to minimize fluid fric~ion losses. The vane is just slightly ~ 20 smaller in diameter than-the orifice 23 so that when it îs in .
.;~ 21 its closed position, as shown in Flg. 4, it is supported by ~he i: 22 rods 26 and 28, and allows a washing backflow through the space l~ ~ 23 thus formed. . .
4 The central circular depression or rec~ss 44 in the convex I ~ 2~ surface 38 is peripherally de~ined by an annular vertical sidewall l~ 2~ 46~ The sidewall 4~ is connected to the convex surface 38 in . 27 asmooth eurved shoulder 50 and to the lower wall 52 of the recess 28 44 by a juncture 54 ha~ing a relatively large radius of curvature.
29 The thicker annular ~ortion 36 of the vane is conne~ted ta the thinner central portion 37 by the wall 46 in~ermedla~e the ~: 31 curved shoulder 50 and the juncture 5~s. .
. -7- -. ., ,.
6~ 5 3 . .
The vane opening support rod 26 includes di~ergi.ng portions 58 and a circumferentially curved hook or knuckle portion 60 joined by shoulders 61. The rod portions 58 are secured to the .
~ ring ~2 on the distal side o the plane 59 through the orifice 23, .. 5 which plane may also be referred to as the genera~ plane of the ; 6 ring 22 since both the ring and the orifice are perpendicular . 7 to an axial line 65 through the cen~er o ~he orifice ana ~he .~ 8 ring. The rod portions extend inwardly anddistally with the 9 portions 58 ~orming an angle b o~ a little.under 30 with the .
plane 5~ of the ~alve. Note that the portions 58 extend distally 11 beyond the edge of the ring ~2. The shoulders 61 curve back .
12 proximally toward the plane 599 thus forming a smooth curve ..
13 intermediate the rod portion 58 and the knuckle portion 60.
14. In ~the prefer.red embodiment, the rod portions 58 diverge ou.twardl~
toward the ring at an angle c of about 60 as shown in Fig. 3.
` 16 The knuckle~portion 60 ~orms an~angle d of a little ~ver~3~ .
17 with respect to portions 58 and angle of about a ~0 angle e ~ 18 ~ith respect to the plane 59. The ~ane opening rod 26~has a -~ 19 diameter: sufficIently large so that its outer surface appr~xi~atel~ .
corresponds to the radius of: curvature of the juncture 54. The 21 radius~f curvat~tre of the knuckle portion 60 is slightly less thar 22 the curvature o the ~sidewalL 46 of~the recess 44 which forms the 2~ other portion of the asymmetric knuckle as shown in Fig~ 3..... ~ .
24 ~The knuckle portion 60 is positioned at the edge of the reces~ :
2~ 44 and extends into the recess to define a contact su~face .
26 which supports the vane during opening. As noted rom Fig. 4 .
27 ~with the vane 24 in its closcd po~sition~ its pariphery 42 is .
28 approximately in the plane of the oriics 23. Becau~ of the :
2g vane convex configuration~ the vane opening support rod portions :
31 58 ext~end distally from the edge 22a of the lo~ proile ring122 ~ 32 ~:
.~ . ~ -8-' .'' ' ".
.
~1~66~3 1 and th~ Icnuclcle 60 of the rod 26 ext:ends into the recess ~4 approximately in the plane of the edge of the ~alve ri.ng 2~..
~ The vane closing support rod 28 as shown in Fig. 3, 4 4 and 5, is ~ symmetrical, complexly sh~ped member includLng assentially straight end por~ions 6~ WhiCh are welded or otherwîse 6 connected to the ring 22 slightly proximal of the orifice plane 59, : 7 which is below the orifice plane in Fi.gs. ~ and 5, in position 8 to support ~he vane in i~s closed position. The straight rod portions 62 extend inwardly :Erom the ring and if continued would '` pass through the axial cen~er line 65 shown in Figs. 3 and 4.11 The angle f formed by the extensions o~ the end portions 62 1~ as shown in Fig. 2 is about 150 in the pre~erred embodi~ent. --~ 13 Howe~er,instead o~ extending straight, the end portlons 62 blend.
. 1~ in~o portions 63 which curve. As seen from Fîg. 3, the end . .
15 portions 62 are both shown on one side of a diameter line 67 .
~:~ 16 in the ori~ice plane 59 with the end portions 6~ being equ~lly . ~ spaced from the line 67. The port;ons 63 eurve on a rather sharp ~ ~ ~ 18 circular arc i~wardly and across the diameter line 67 such that.: ~ 19 i continued, they would once more intersect the valve ring 22. .
8 ¦ illustrating the prosthesis, it will be discussed primarily as 9 ¦ an aortic valve replacement.
10 ¦ As shown in Figs . 2, 3 and 4, the structure o the prosthesis 11 I 10 in~ludes a metallic valve ring 22 having an ~nn~r wall.which 12 I de:Eines a valve orifice through which the blood fLows as ~ .
13 I controlled~by a movable valve occluder in the form of a discoid 14 ¦ vane 24. (The vane is not truly a disc, although that term is 1~ ¦.loosely applied to the vane, and the term lldiscoid~ is not 16 ¦ used in any technical sense but is selected merely to suggest 17 ¦ a body which is roundg has an overall thickness less than ~he 18 ¦ diame~er and has a comple~ configuration which is nu~ easily lg~ described except by function and on a portion by portio~ basis.
An~ body which is 50 conrigured as to function in the manner ~l described hereinafter may be regarded as disco;dO) A vane 22 opening support rod 26 and a vane closing support rod 28 have 23 their ends attached~to the valve ring 22 by welding or other 24: suitable means to support the vane for movement within the valve 25 ring 22. Suitable means, ~such as suture ring 23, is secured .
2~ about the ~alve ring for connecting the valve to ~he heart or 27 aortic tissue. One such arrangement is described in ~he above .
28 mentioned ShiLey patent. . ~ .
29 From Fig. ~, it may be seen that the valve vane 24 has a conve~o-concave, saucer-like con~iguration, with the convex . ~ -6- . .
~,` . : . .
~ 10668S3 1 surface 38 having a concentri.c recess ~4 which cre~es an annular 2 van~ portion 36 and a thinner central portion 37. The diska ~ surace 38 of the ~ane 24 has a convex curvat-lre formed on a 4 radius o~ curvature which in a preferred form of the inven~ion is about equal to t~le diameter of the varle 24. The proximal sur~ace 6 40 of ~he vane has a concave curva~ure about a radius of curvature 7 of which in a preferred form of the irlvention is generally in 8 the range of two or three times the radius of curyature of the 9 distal convex surface 38.
The peripheraledge 42 of the vane 24 is ro~mded to lie, 11 in the closed position, adjacent to and, in the pre~erred ~orm, 12 spaced slightly from the inner surface 23 o~ the valve ring 22 ~ 13 which forms:the ori~ice through which the blood flows. In a :. . preferred form of the invention, the ~hickness of ~he edge 42 .
. 15 where the edge curvature starts is greater than the thickne~ss .
~` ~ 16 of the vane cen~ral portion 37. This indicates the ligh~ .
17 weight, low profile of the vane. The ring 22 has the shape of 18 a toroidal sectian with the inner surace being smoothly rounded 19 to minimize fluid fric~ion losses. The vane is just slightly ~ 20 smaller in diameter than-the orifice 23 so that when it îs in .
.;~ 21 its closed position, as shown in Flg. 4, it is supported by ~he i: 22 rods 26 and 28, and allows a washing backflow through the space l~ ~ 23 thus formed. . .
4 The central circular depression or rec~ss 44 in the convex I ~ 2~ surface 38 is peripherally de~ined by an annular vertical sidewall l~ 2~ 46~ The sidewall 4~ is connected to the convex surface 38 in . 27 asmooth eurved shoulder 50 and to the lower wall 52 of the recess 28 44 by a juncture 54 ha~ing a relatively large radius of curvature.
29 The thicker annular ~ortion 36 of the vane is conne~ted ta the thinner central portion 37 by the wall 46 in~ermedla~e the ~: 31 curved shoulder 50 and the juncture 5~s. .
. -7- -. ., ,.
6~ 5 3 . .
The vane opening support rod 26 includes di~ergi.ng portions 58 and a circumferentially curved hook or knuckle portion 60 joined by shoulders 61. The rod portions 58 are secured to the .
~ ring ~2 on the distal side o the plane 59 through the orifice 23, .. 5 which plane may also be referred to as the genera~ plane of the ; 6 ring 22 since both the ring and the orifice are perpendicular . 7 to an axial line 65 through the cen~er o ~he orifice ana ~he .~ 8 ring. The rod portions extend inwardly anddistally with the 9 portions 58 ~orming an angle b o~ a little.under 30 with the .
plane 5~ of the ~alve. Note that the portions 58 extend distally 11 beyond the edge of the ring ~2. The shoulders 61 curve back .
12 proximally toward the plane 599 thus forming a smooth curve ..
13 intermediate the rod portion 58 and the knuckle portion 60.
14. In ~the prefer.red embodiment, the rod portions 58 diverge ou.twardl~
toward the ring at an angle c of about 60 as shown in Fig. 3.
` 16 The knuckle~portion 60 ~orms an~angle d of a little ~ver~3~ .
17 with respect to portions 58 and angle of about a ~0 angle e ~ 18 ~ith respect to the plane 59. The ~ane opening rod 26~has a -~ 19 diameter: sufficIently large so that its outer surface appr~xi~atel~ .
corresponds to the radius of: curvature of the juncture 54. The 21 radius~f curvat~tre of the knuckle portion 60 is slightly less thar 22 the curvature o the ~sidewalL 46 of~the recess 44 which forms the 2~ other portion of the asymmetric knuckle as shown in Fig~ 3..... ~ .
24 ~The knuckle portion 60 is positioned at the edge of the reces~ :
2~ 44 and extends into the recess to define a contact su~face .
26 which supports the vane during opening. As noted rom Fig. 4 .
27 ~with the vane 24 in its closcd po~sition~ its pariphery 42 is .
28 approximately in the plane of the oriics 23. Becau~ of the :
2g vane convex configuration~ the vane opening support rod portions :
31 58 ext~end distally from the edge 22a of the lo~ proile ring122 ~ 32 ~:
.~ . ~ -8-' .'' ' ".
.
~1~66~3 1 and th~ Icnuclcle 60 of the rod 26 ext:ends into the recess ~4 approximately in the plane of the edge of the ~alve ri.ng 2~..
~ The vane closing support rod 28 as shown in Fig. 3, 4 4 and 5, is ~ symmetrical, complexly sh~ped member includLng assentially straight end por~ions 6~ WhiCh are welded or otherwîse 6 connected to the ring 22 slightly proximal of the orifice plane 59, : 7 which is below the orifice plane in Fi.gs. ~ and 5, in position 8 to support ~he vane in i~s closed position. The straight rod portions 62 extend inwardly :Erom the ring and if continued would '` pass through the axial cen~er line 65 shown in Figs. 3 and 4.11 The angle f formed by the extensions o~ the end portions 62 1~ as shown in Fig. 2 is about 150 in the pre~erred embodi~ent. --~ 13 Howe~er,instead o~ extending straight, the end portlons 62 blend.
. 1~ in~o portions 63 which curve. As seen from Fîg. 3, the end . .
15 portions 62 are both shown on one side of a diameter line 67 .
~:~ 16 in the ori~ice plane 59 with the end portions 6~ being equ~lly . ~ spaced from the line 67. The port;ons 63 eurve on a rather sharp ~ ~ ~ 18 circular arc i~wardly and across the diameter line 67 such that.: ~ 19 i continued, they would once more intersect the valve ring 22. .
5.' 20 The curved portions 63 pass through an arc of sligh~ly less ~han .
21 90 and then connect to a curved central portio~ 64 by means of .
22 smooth curved shoulders 66. As seen ~rom Fig. 4, the ~urved 23 portions 63 also slope toward and across the orifice pl~ne 59 2~ on a ~arge radius of curvature to conform to the concave surace : 25 of the varle 24. The shoulders 66 curve back toward and across ` 26 ~he orifice plane at an angle away -from the plane or away froTn ~5 ~ ~27 :the vane 24 when shown in its closed position in Fig. 4. The i~ 2B shoulders 66 ~n~le radially outwardly preerably at an angle g 29 ~of abou 20 wlth respect to the axial cen~er line 65 of the va~ve .
:: : 30 .
: 32 ~
. _9_ .
' ~ . , . -...... ... ~ . . ~ . . .. . .
~L066853 1 ¦ as may ba seen in Fig~ 4. The central portion 6~ connects the 2 ¦ shoulders 66 and curves sligh~ly radially outwardLy from t-he ~¦ axial center line ~5 of the valve on a very large radius o~
~¦ curvature in a plane approximately parallel to the orlEice 51 plane 59. The various portions o-E the vane opening rod 28 acing 61 the vane form a continuous smooth, curved, camming surface over 7 ¦ which the concave sur~ace ~0 of the vane can rlde when the vane 8 ¦ is being closed. As may be seen from Fig. 4, the camming sur~aces 9 ¦ on the shoulders 66 are substantialLy subjacent the opening rod 10 ¦ knuckle portion 60 for defining a loose~ overcenter rocker .
ll ¦ suppor~ ~or ~he vane during closure.
12 ¦ The spacing between ~he upper shoulders 66 and the knuckle 13 ¦ 60 on the vane opening support rod 26 is smaller than the thic~ness 14 ¦ of the thickest part of the annular por~:ion 36 of the v2ne 24 15 ¦ between the conca~e-convex vane surfaces ~o that the vane canno:t .
16 ¦ slip out of the ~alve assembly. T~at is, the vane is supported . :
17 ¦ and confined by ~he rods 26 and 28 in cooperation wi~h the vaLve 18 ¦ ring 22~ ~
19 ¦ During operation of the aortic heart val~e prosthesis of 20 ¦ this inuention, the valve v~ne 2~ responds to blood pressure .
21 ¦~pulses created by the hea~t. The ~ane is hemodynamically opened .
22 ¦ by systolic contraction of thP left ventricle which forces blood 23 against the concave proximal surface 40~of~the ~ane. The vane .
24~ immediately moves away from the lower vane closing support rod .
25. 28 and into engagement with ~he knuckla 60 of the opening support .
26 rod 26 in~the edge of ~he central recess 44~ The contacting 27 ~surface is a short ~ircular line contac~, an asymmetrical .
28 knuckle contact~ Since the contact between the van~ and ~he rod 2~ is eccen~r~c with respect to ~he center of the vane or ~he ax~al :
30 : . .
31 .
32 : . . .
. ' -10-..... , 1: - , .
~G853 center line 65, the forces actlng agalnst the vane tilt the vane open around the knuckle. The openlng movement is loosely con-trolled by the combined action of the knuckle 60 of the opening support rod 26 and the center portion 64 oE the closing support rod 28 and the ring 22. The movement during opening is a wobbly tilting action because oE the loose fit. This is advantageous because the vane can react to variations in the fluid flow through the valve.; As seen in Fig. ff, the center portion 64 of the support rod limits the opening of the vane. Essentlally a line contact is formed between the center portion 64 of the .
proximal support rod and the concave surface of the vane. The ` vane periphery 42 may also lightly touch a portion oE the ring 22 if the vane is off center with respect to the support base i 24.
. ~ .
, In a preferred embodiment, the spacing between the ', i` '. - .: ' upper support rod ~nuckle 60 and the center portion 64 of the ., , . , ~ ,.: .
proximal support rod is sufficient to enable the valve vane to open to an angle a, shown in Fig. 6, of about 60 from the ~ . . . .
j ~ orifice plane. It has been found that the pressure gradient t'i 20 as a function of opening angle is such that satisfactory opera-tion is obtained even if the vane is limited to an opening angle '~j 50 . An opening angle a in the range from 50 to ~0 is quite -' satisfactory from that standpoint. At values higher than 80 , the pressure gradient is not reduced by an appreciable amount while the response time is increased due to the longer distance the vane must travel.
The fitting of the central curved section of the .,,~ , .
proximal support rod into the Juncture 54 of the recess 44 on the :,d~ ~ vane enhances the opening motion so that relatively little pres-~j~30 sure is required to open the valve. The light weight of the vane '~ ~ : . :- . . .
1 and .. .
,~ - 11 -.:
.! .
~L066853 l the eccentric mounting of the central portion 60 is such that 2 in;tial opening gradients are on the order oE two to five 3 millimeters of m~rcury.
4 I~ should be noted that in the valve open position o~ Fig.
21 90 and then connect to a curved central portio~ 64 by means of .
22 smooth curved shoulders 66. As seen ~rom Fig. 4, the ~urved 23 portions 63 also slope toward and across the orifice pl~ne 59 2~ on a ~arge radius of curvature to conform to the concave surace : 25 of the varle 24. The shoulders 66 curve back toward and across ` 26 ~he orifice plane at an angle away -from the plane or away froTn ~5 ~ ~27 :the vane 24 when shown in its closed position in Fig. 4. The i~ 2B shoulders 66 ~n~le radially outwardly preerably at an angle g 29 ~of abou 20 wlth respect to the axial cen~er line 65 of the va~ve .
:: : 30 .
: 32 ~
. _9_ .
' ~ . , . -...... ... ~ . . ~ . . .. . .
~L066853 1 ¦ as may ba seen in Fig~ 4. The central portion 6~ connects the 2 ¦ shoulders 66 and curves sligh~ly radially outwardLy from t-he ~¦ axial center line ~5 of the valve on a very large radius o~
~¦ curvature in a plane approximately parallel to the orlEice 51 plane 59. The various portions o-E the vane opening rod 28 acing 61 the vane form a continuous smooth, curved, camming surface over 7 ¦ which the concave sur~ace ~0 of the vane can rlde when the vane 8 ¦ is being closed. As may be seen from Fig. 4, the camming sur~aces 9 ¦ on the shoulders 66 are substantialLy subjacent the opening rod 10 ¦ knuckle portion 60 for defining a loose~ overcenter rocker .
ll ¦ suppor~ ~or ~he vane during closure.
12 ¦ The spacing between ~he upper shoulders 66 and the knuckle 13 ¦ 60 on the vane opening support rod 26 is smaller than the thic~ness 14 ¦ of the thickest part of the annular por~:ion 36 of the v2ne 24 15 ¦ between the conca~e-convex vane surfaces ~o that the vane canno:t .
16 ¦ slip out of the ~alve assembly. T~at is, the vane is supported . :
17 ¦ and confined by ~he rods 26 and 28 in cooperation wi~h the vaLve 18 ¦ ring 22~ ~
19 ¦ During operation of the aortic heart val~e prosthesis of 20 ¦ this inuention, the valve v~ne 2~ responds to blood pressure .
21 ¦~pulses created by the hea~t. The ~ane is hemodynamically opened .
22 ¦ by systolic contraction of thP left ventricle which forces blood 23 against the concave proximal surface 40~of~the ~ane. The vane .
24~ immediately moves away from the lower vane closing support rod .
25. 28 and into engagement with ~he knuckla 60 of the opening support .
26 rod 26 in~the edge of ~he central recess 44~ The contacting 27 ~surface is a short ~ircular line contac~, an asymmetrical .
28 knuckle contact~ Since the contact between the van~ and ~he rod 2~ is eccen~r~c with respect to ~he center of the vane or ~he ax~al :
30 : . .
31 .
32 : . . .
. ' -10-..... , 1: - , .
~G853 center line 65, the forces actlng agalnst the vane tilt the vane open around the knuckle. The openlng movement is loosely con-trolled by the combined action of the knuckle 60 of the opening support rod 26 and the center portion 64 oE the closing support rod 28 and the ring 22. The movement during opening is a wobbly tilting action because oE the loose fit. This is advantageous because the vane can react to variations in the fluid flow through the valve.; As seen in Fig. ff, the center portion 64 of the support rod limits the opening of the vane. Essentlally a line contact is formed between the center portion 64 of the .
proximal support rod and the concave surface of the vane. The ` vane periphery 42 may also lightly touch a portion oE the ring 22 if the vane is off center with respect to the support base i 24.
. ~ .
, In a preferred embodiment, the spacing between the ', i` '. - .: ' upper support rod ~nuckle 60 and the center portion 64 of the ., , . , ~ ,.: .
proximal support rod is sufficient to enable the valve vane to open to an angle a, shown in Fig. 6, of about 60 from the ~ . . . .
j ~ orifice plane. It has been found that the pressure gradient t'i 20 as a function of opening angle is such that satisfactory opera-tion is obtained even if the vane is limited to an opening angle '~j 50 . An opening angle a in the range from 50 to ~0 is quite -' satisfactory from that standpoint. At values higher than 80 , the pressure gradient is not reduced by an appreciable amount while the response time is increased due to the longer distance the vane must travel.
The fitting of the central curved section of the .,,~ , .
proximal support rod into the Juncture 54 of the recess 44 on the :,d~ ~ vane enhances the opening motion so that relatively little pres-~j~30 sure is required to open the valve. The light weight of the vane '~ ~ : . :- . . .
1 and .. .
,~ - 11 -.:
.! .
~L066853 l the eccentric mounting of the central portion 60 is such that 2 in;tial opening gradients are on the order oE two to five 3 millimeters of m~rcury.
4 I~ should be noted that in the valve open position o~ Fig.
6, the proxîmal edge o~ the vane, which is the leading or upstream . edge, presents very little blocking or occluding sur~ace to the
7 blood stream. A line 73 whi~h is tange~nt to the concave vane .
8 sur~ace 38 at the point 38a where the concave surace blends
9 into the cur~ature of the peripheral edge 42 o~ the ~ane is approximately parallel to the center line 65 of the valve, which iiC
ll the predominate direction of blood flow. In practice the tangent .
..... -l~ 73 may vary a few degrees, e.g.7 up to 5 to 8 degrees in either l~ direction, from being parallel to the blood stream 14 or the ce~ter line 65~ As a result, the area s o~ the opening .
~5 between the edge of the vane 24 on the proximal ~ide o the vaLveg .:
~6 as shown in Fig. 6, and the adjacent ~ide of the ring 2~ to .
17 which the vane opening rod 26 is attached3 is ~onsiderably 18 increased from-the area of the analogous opening in prior valves .
19 shown in t:he above mentioned Shiley patent. In other wor~ls~, ~he percentage of blood flow in this small~r ori~ice area s is 21 defined by the convex surface of the vane and the adjacent ring 22 portio11 with respect to the total flow through the valve has .
increased significantly, as much as 50% over the percen~age .
24 of bLood flow through the ana~ogous area in the prior Shiley 25 ~alve which had vanes with f~at or straight sloping sides. The 26: main advantage of this arrangement is that th~ increased blood 7 flow in this area reduces the chance of thrombus because of the .
28 ~dditional washing in that area without increase in th~ pressure :
29 gradi~nt across the vaLve. .
30 Another advant~ge of the eonvexo-coneave vane is that the .
3I vane extends a considerab1e distance dista1ly of the valve ring -. ' ~ - . .
. ~ .
~ ~ ~ ~ ~2- - .
~ ` 1066853 .
1 when the vane is in the open position of Fig. 6 because the knuckle 60 of the vane openitlg support rod 26 ~s sp~ced considerably 3 distal to ~he orifice plane because the shape of the vane positions the vane juncture 54 in the recess 4~ at this location. The eIItire vane 24 is ~hus positioned downstream further in the 6 valve ring 2~ in the vane open position. The importan~.e of this 7 is that the portions of the ~dge 42 oiE the vane closest to the 8 valve ring 22 are normally spaced further from the ring than .. 9 in the prior art valve. Consequently, blood can flow between 1 the edges of the vane and the valve ring thus reducing resistance 1l to flow and, more importantl~, further minimizing the likelihood 12 of thrombus formations at those ~wo points. While one portion ~
13 of tha vane edge may touch one portion of the valve ring 22 in .
14 the open position, the vane c~n wobble and move slightly from side to side during repeated opening and cIosing cycles with .~~ 16~ the results:that incre~sed blood washing is attained between the: ~ ~lq :edges of the vane and the ring 22. : ~: 18 ~At the onset sf diastole,~ the pressure in the left ventrical -19 ~drops to zero and the pressure .o~ the blood in the aorta acts 20~ in the reverse .direction-on the vane, causing vane~t~ slip toward 21 the proximaL side of the valve out of contact with the dista~ly ` ~ 22 located opening support rod 26.and tc beg;n to rock clos~ on the . 23 camming surface of the pro~imally located closing support rod.
24: The~ edge~42 of the vane contacts the ring a~ two points thus .
25 Iimiting the:lateral slip o~ the vane. In;~ial con~act of the ..
26 concav~ surface of the vane 24 and the vane closing support rod 2~ 28 is highly eccentric and the initial closîng pressure is 28 distributed over~a large portion of the vane above the ori~ice 29 ~or ring plane 59.~ As the ~ane clos~s, howaver, the dist~nce~`
.
3l : 13 . ~ , :- . . .
. : .
,., .. ,. . . . .. .,. . , . - .. ~.... ~ .. .. , . . ~ . - . - .. . .
~L066853 1 between the contact area o~ the support rod ~lth the surEace o~
2 the vane and the diameter line 67 of Fig. 3 clecreases as tha vane 3 engages the shoulder 66, the curved yortion 63 and the end portion 62. Immedia~ely prior to closing, the line of contact îs at about the diameter line o~ the vane so that the vane closing forces which act on one half of the convex sur~ace of the vane to 7 close it are balanced by similar forces which act on the other 8 hal of the convex surface of the vane and tend to open it. This 9 condition is attributable to the migraking line of contact which moves along the camming surfaces of the vane closing rod 28 11 as the vane closes in a rocking motion, much as the contact point 12 of the rockers of a rocking chair moves to and fro as the chair 13 is rocked. The closing acceleration of the ~ane is thus reduced 14 significantly by this migr~tion of the line of con~ac~. The vane opening rod 26 limits the movement of the vane beyond the 16 cLosed position. ~
17 As the vane opens and cLoses, it momentarily wobbles and 18 floats between the support rods and rotates in the plane o the ~19 vane thereby evenly distributin~ ~he forces on the vane and reducing problems of thr~mbosis and protein buildup that is more 21 likely to occur with a fixed hinge vane. That is, with such 22 rotation, the contact between the vane and the support rods 25 23 and 28 does not always occur at the sama point so that all sur aces of the v~ne continue to be washed thoroughly. This also has the important advantage tha~ wear is evenly dis~rlbuted on the vane 26 with the result that the projected life of the vane is enhanced.
27~ Table I shows the preferred dimensions, radii, etc., for 2B standard valve sizes and is included as an aid to understanding the 29 invention and for completeness of disclosure with the understandin~
that~hese values are exemplary, subject to great variation, and 31 .
",, . ,.. ,,,.. ,,~ ,,.. ,"",, , ""~, ...
`--~
i6853 nonlimiting ~ to the ~cope oR the lnYent~c)n. The values llsted are in milllmeters and are rounded of~ to thc num~er o~
significant ~igures shown.
TABLE l Valve Vane Prox Distal Well Well Edge Webb Size Dia. Radius Radlus Dia, Depth Radius Thickness (1) (2)~3) (4) (5)(6) (7) (8) 21 15.9 15.5 48.38.2 1.04 .43 .76 23 17.7 17.3 53.58.9 1.07 ~43 .76 ` 10 25 19.9 19.5 47.810.2 1.17 .43 .76 - 27 22.0 21.5 45.011.2 1.17 .43 .76 ` 29 24.0 23.6 45.012.1 1017 .43 .76 ~-~ The present invention contemplates any number of variations ,i .
Il and alternatives to the e~emplary structures depicted and descrlbed.
.~, :
.1: . .
~, ! : -:
. .
. . .
. ~:
.: ..
(1) Tissue annulus diameter.
(2) Diameter of the Discoid vane.
(3) Radius of curvature of the proxlmal surEace.
!; .
(4) Radius of curvature of the distal surface.
(5~ Diameter of the central depression or well.
(6? Depth of the central depression or well.
~i~ 30 ,~ (7) Radius of curvature of the peripheral edge of the vane.
~8) Thickness of the vane measured from the bo~tom of the central depression or well to the proximal surface.
~ 1~ '106~853 1 One illustrative alternative is depicted in Figure 7 in whi¢h the 2 same numerals are used or the structu-r~s and features previously described. The exemplary embodiment of Figure 7 dif~ers from ~l the prefe~red embodiment previously described i~ that the strut element 5~a replaces the closing rod 26. The tip 60a of the 6 opening support element 58a is rounded to a hemisphere having 7 a radius of curvature equal to the radius of the wire from which 8 the element is formed. Except for the area of contact~ th~ s-lpport 9 strut 58a cooperates wi~h the occluder in the ma~ner previously described, the contact area in the present em~odiment being ll smaller at some times during the opening phase than the contact 12 area of the pre~iously desc~ibed embocliment. Another minor -- difference is that in the embodiment of Figure 7, the centraL
-~ 14 depression 44 is replaced by a circular depression 44a and a~
raised cen~er ~5. This is, quite clearly, merely an equivalent variation of the struc~ure previously described~ aIthough there 17 may be some hemodynamic advantages to the pre~erred embodime~t.
~- lB In a preferred form, the sutur~ ring îs made of a Teflon ~ -l9 polytetrafluoroethylene pad covered with-Teflon fabric~
i~ 20 the val~e ring and support rods are made of a corrosion res;stan~21 `material such as Haynes 25 or stellite cobal~ alloy, and the ~2 occluder, the vane 24, is made of grap~ite coated with a thick 23 skin o vapor deposited pyrolytic carbon, such as occluders 4 made and sold by Gulf Energy & En~ironmental Systems under the trademark P ~ OLITE, the manufacture and characteristics of which 26 are well described in the prior art. Other materials may, 27 of course, be used.
28 Other variations~and changes in structure can be made if 29 the eBsential function o the invention is preserved without 30 departing from,khe~scope of the i~vention as deEine~ in ~he 31 ~ollowing claims:
3~ /l
ll the predominate direction of blood flow. In practice the tangent .
..... -l~ 73 may vary a few degrees, e.g.7 up to 5 to 8 degrees in either l~ direction, from being parallel to the blood stream 14 or the ce~ter line 65~ As a result, the area s o~ the opening .
~5 between the edge of the vane 24 on the proximal ~ide o the vaLveg .:
~6 as shown in Fig. 6, and the adjacent ~ide of the ring 2~ to .
17 which the vane opening rod 26 is attached3 is ~onsiderably 18 increased from-the area of the analogous opening in prior valves .
19 shown in t:he above mentioned Shiley patent. In other wor~ls~, ~he percentage of blood flow in this small~r ori~ice area s is 21 defined by the convex surface of the vane and the adjacent ring 22 portio11 with respect to the total flow through the valve has .
increased significantly, as much as 50% over the percen~age .
24 of bLood flow through the ana~ogous area in the prior Shiley 25 ~alve which had vanes with f~at or straight sloping sides. The 26: main advantage of this arrangement is that th~ increased blood 7 flow in this area reduces the chance of thrombus because of the .
28 ~dditional washing in that area without increase in th~ pressure :
29 gradi~nt across the vaLve. .
30 Another advant~ge of the eonvexo-coneave vane is that the .
3I vane extends a considerab1e distance dista1ly of the valve ring -. ' ~ - . .
. ~ .
~ ~ ~ ~ ~2- - .
~ ` 1066853 .
1 when the vane is in the open position of Fig. 6 because the knuckle 60 of the vane openitlg support rod 26 ~s sp~ced considerably 3 distal to ~he orifice plane because the shape of the vane positions the vane juncture 54 in the recess 4~ at this location. The eIItire vane 24 is ~hus positioned downstream further in the 6 valve ring 2~ in the vane open position. The importan~.e of this 7 is that the portions of the ~dge 42 oiE the vane closest to the 8 valve ring 22 are normally spaced further from the ring than .. 9 in the prior art valve. Consequently, blood can flow between 1 the edges of the vane and the valve ring thus reducing resistance 1l to flow and, more importantl~, further minimizing the likelihood 12 of thrombus formations at those ~wo points. While one portion ~
13 of tha vane edge may touch one portion of the valve ring 22 in .
14 the open position, the vane c~n wobble and move slightly from side to side during repeated opening and cIosing cycles with .~~ 16~ the results:that incre~sed blood washing is attained between the: ~ ~lq :edges of the vane and the ring 22. : ~: 18 ~At the onset sf diastole,~ the pressure in the left ventrical -19 ~drops to zero and the pressure .o~ the blood in the aorta acts 20~ in the reverse .direction-on the vane, causing vane~t~ slip toward 21 the proximaL side of the valve out of contact with the dista~ly ` ~ 22 located opening support rod 26.and tc beg;n to rock clos~ on the . 23 camming surface of the pro~imally located closing support rod.
24: The~ edge~42 of the vane contacts the ring a~ two points thus .
25 Iimiting the:lateral slip o~ the vane. In;~ial con~act of the ..
26 concav~ surface of the vane 24 and the vane closing support rod 2~ 28 is highly eccentric and the initial closîng pressure is 28 distributed over~a large portion of the vane above the ori~ice 29 ~or ring plane 59.~ As the ~ane clos~s, howaver, the dist~nce~`
.
3l : 13 . ~ , :- . . .
. : .
,., .. ,. . . . .. .,. . , . - .. ~.... ~ .. .. , . . ~ . - . - .. . .
~L066853 1 between the contact area o~ the support rod ~lth the surEace o~
2 the vane and the diameter line 67 of Fig. 3 clecreases as tha vane 3 engages the shoulder 66, the curved yortion 63 and the end portion 62. Immedia~ely prior to closing, the line of contact îs at about the diameter line o~ the vane so that the vane closing forces which act on one half of the convex sur~ace of the vane to 7 close it are balanced by similar forces which act on the other 8 hal of the convex surface of the vane and tend to open it. This 9 condition is attributable to the migraking line of contact which moves along the camming surfaces of the vane closing rod 28 11 as the vane closes in a rocking motion, much as the contact point 12 of the rockers of a rocking chair moves to and fro as the chair 13 is rocked. The closing acceleration of the ~ane is thus reduced 14 significantly by this migr~tion of the line of con~ac~. The vane opening rod 26 limits the movement of the vane beyond the 16 cLosed position. ~
17 As the vane opens and cLoses, it momentarily wobbles and 18 floats between the support rods and rotates in the plane o the ~19 vane thereby evenly distributin~ ~he forces on the vane and reducing problems of thr~mbosis and protein buildup that is more 21 likely to occur with a fixed hinge vane. That is, with such 22 rotation, the contact between the vane and the support rods 25 23 and 28 does not always occur at the sama point so that all sur aces of the v~ne continue to be washed thoroughly. This also has the important advantage tha~ wear is evenly dis~rlbuted on the vane 26 with the result that the projected life of the vane is enhanced.
27~ Table I shows the preferred dimensions, radii, etc., for 2B standard valve sizes and is included as an aid to understanding the 29 invention and for completeness of disclosure with the understandin~
that~hese values are exemplary, subject to great variation, and 31 .
",, . ,.. ,,,.. ,,~ ,,.. ,"",, , ""~, ...
`--~
i6853 nonlimiting ~ to the ~cope oR the lnYent~c)n. The values llsted are in milllmeters and are rounded of~ to thc num~er o~
significant ~igures shown.
TABLE l Valve Vane Prox Distal Well Well Edge Webb Size Dia. Radius Radlus Dia, Depth Radius Thickness (1) (2)~3) (4) (5)(6) (7) (8) 21 15.9 15.5 48.38.2 1.04 .43 .76 23 17.7 17.3 53.58.9 1.07 ~43 .76 ` 10 25 19.9 19.5 47.810.2 1.17 .43 .76 - 27 22.0 21.5 45.011.2 1.17 .43 .76 ` 29 24.0 23.6 45.012.1 1017 .43 .76 ~-~ The present invention contemplates any number of variations ,i .
Il and alternatives to the e~emplary structures depicted and descrlbed.
.~, :
.1: . .
~, ! : -:
. .
. . .
. ~:
.: ..
(1) Tissue annulus diameter.
(2) Diameter of the Discoid vane.
(3) Radius of curvature of the proxlmal surEace.
!; .
(4) Radius of curvature of the distal surface.
(5~ Diameter of the central depression or well.
(6? Depth of the central depression or well.
~i~ 30 ,~ (7) Radius of curvature of the peripheral edge of the vane.
~8) Thickness of the vane measured from the bo~tom of the central depression or well to the proximal surface.
~ 1~ '106~853 1 One illustrative alternative is depicted in Figure 7 in whi¢h the 2 same numerals are used or the structu-r~s and features previously described. The exemplary embodiment of Figure 7 dif~ers from ~l the prefe~red embodiment previously described i~ that the strut element 5~a replaces the closing rod 26. The tip 60a of the 6 opening support element 58a is rounded to a hemisphere having 7 a radius of curvature equal to the radius of the wire from which 8 the element is formed. Except for the area of contact~ th~ s-lpport 9 strut 58a cooperates wi~h the occluder in the ma~ner previously described, the contact area in the present em~odiment being ll smaller at some times during the opening phase than the contact 12 area of the pre~iously desc~ibed embocliment. Another minor -- difference is that in the embodiment of Figure 7, the centraL
-~ 14 depression 44 is replaced by a circular depression 44a and a~
raised cen~er ~5. This is, quite clearly, merely an equivalent variation of the struc~ure previously described~ aIthough there 17 may be some hemodynamic advantages to the pre~erred embodime~t.
~- lB In a preferred form, the sutur~ ring îs made of a Teflon ~ -l9 polytetrafluoroethylene pad covered with-Teflon fabric~
i~ 20 the val~e ring and support rods are made of a corrosion res;stan~21 `material such as Haynes 25 or stellite cobal~ alloy, and the ~2 occluder, the vane 24, is made of grap~ite coated with a thick 23 skin o vapor deposited pyrolytic carbon, such as occluders 4 made and sold by Gulf Energy & En~ironmental Systems under the trademark P ~ OLITE, the manufacture and characteristics of which 26 are well described in the prior art. Other materials may, 27 of course, be used.
28 Other variations~and changes in structure can be made if 29 the eBsential function o the invention is preserved without 30 departing from,khe~scope of the i~vention as deEine~ in ~he 31 ~ollowing claims:
3~ /l
Claims (12)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. In a heart valve prosthesis having a valve ring, means for securing the valve ring in the place of a natural heart valve, a free floating, rotatable, discoid valve occluder and means for mounting the occluder for repetitive movement between the open and closed positions, the improvement wherein:
the valve occluder is a vane having radial symmetry about a center axis perpendicular to the general plane of the vane, and having a generally arcuate convex distal surface with a distal depression surrounding the center of the vane and having a concave proximal surface which is generally arcuate with a large arc of curvature to define a thin disc with a relatively smooth proximal surface; and the mounting means comprising opening support structure extending on the distal side of the occluder from the valve ring to the depression in the vane, the inner portion of the opening support structure extending into the depression to engage therein to control the opening movement of the occluder and to provide a knuckle-like joint between the opening support structure and the occluder during opening; and a closing support structure extending from the ring into the arcuate concavity of the proximal surface to provide a rocker-like contact support surface for the occluder during closure, the contact between the support surface and the occluder moving toward the center during closure said mounting means permitting free rotation of said occluder about its center as the occluder opens and closes.
the valve occluder is a vane having radial symmetry about a center axis perpendicular to the general plane of the vane, and having a generally arcuate convex distal surface with a distal depression surrounding the center of the vane and having a concave proximal surface which is generally arcuate with a large arc of curvature to define a thin disc with a relatively smooth proximal surface; and the mounting means comprising opening support structure extending on the distal side of the occluder from the valve ring to the depression in the vane, the inner portion of the opening support structure extending into the depression to engage therein to control the opening movement of the occluder and to provide a knuckle-like joint between the opening support structure and the occluder during opening; and a closing support structure extending from the ring into the arcuate concavity of the proximal surface to provide a rocker-like contact support surface for the occluder during closure, the contact between the support surface and the occluder moving toward the center during closure said mounting means permitting free rotation of said occluder about its center as the occluder opens and closes.
2. The heart vane prosthesis defined in claim 1 wherein the radius of curvature of the arc of the convex distal side of the vane is approximately equal to the diameter of the vane.
3. The heart valve prosthesis defined in claim 2 wherein the radius of curvature of the arc of the concave proximal side of the vane is approximately two to three times the radius of curvature of the arc of the convex distal surface.
4. The heart valve phosthesis defined in claim 1 wherein the opening and closing support structure are so constructed and configured in respect to each other and the vane that when the vane is full open a tangent to the arcuate convex distal surface adjacent the edge thereof is approximately parallel to a central axis taken normal to the plane of the valve ring.
5. The heart valve prosthesis defined in claim 4 wherein the radius of curvature of the arc of the concave proximal side of the vane is approximately two to three times the radius of curvature of the arc of the convex distal surface.
6. The heart valve prosthesis defined in claim 5 wherein the radius of curvature of the arc of the convex distal side of the vane is approximately equal to the diameter of the vane.
7. A heart valve prosthesis, comprising: a valve ring having a passage for blood therethrough; means for securing the valve ring in the place of a natural heart valve; a valve occluder in the form of a discoid vane having radial symmetry about a center axis perpendicular to the general plane of the valve occluder, and having an arcuately curved concave proximal side with a single large arc of curvature to define a thin disc with a relatively smooth proximal surface and a distal side which is generally arcuately curved and convex and has a depression therein; distal opening support structure extending from the valve ring into the passage and then in the proximal direction into the depression in the distal side of the occluder vane to form therewith a knuckle-like joint about which the vane moves as it opens in response to pressure applied in the distal direction; and proximal closing support structure extending from the valve ring into the passage and in the distal direction in curved configuration into the arcuate concavity of the vane to provide a rocker-like support for the vane as the vane closes in response to pressure applied in the proximal direction, the closing support being so configured in relation to the arcuate concave surface that the contact area between the closing support and the vane moves toward the center of the vane during closure thereby reducing the eccentric closing force as the valve closes; the opening and closing support structures cooperatively defining the maximum open position of the vane such that blood flows over the arcuate convex distal surface and the arcuate concave proximal surface when the valve is opened by the pressure of blood applied in the distal direction; the opening and closing support structure cooperating with the occluder to permit the occluder to rotate about its center axis as it opens and closes.
8. The heart valve prosthesis defined in claim 7 wherein the radius of curvature of the arc of the concave proximal side of the vane is approximately two to three times the radius of curvature of the arc of the convex distal surface.
9. The heart valve prosthesis defined in claim 8 wherein the radius of curvature of the arc of the convex distal side of the vane is approximately equal to the diameter of the vane.
10. The heart valve prosthesis defined in claim 7 wherein the opening and closing support structures are so constructed and configured in response to each other and the vane that when the vane is full open a tangent to the arcuate convex distal surface adjacent the edge thereof is approximately parallel to a central axis taken normal to the plane of the valve ring.
11. The heart valve prosthesis defined in claim 10 wherein the radius of curvature of the arc of the concave proximal side of the vane is approximately two to three times the radius of curvature of the arc of the convex distal surface.
12. The heart valve prosthesis defined in claim 11 wherein the radius of curvature of the arc of the convex distal side of the vane is approximately equal to the diameter of the vane.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US05/611,273 US4057857A (en) | 1975-09-08 | 1975-09-08 | Heart valve with arcuate occluder |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1066853A true CA1066853A (en) | 1979-11-27 |
Family
ID=24448366
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA259,375A Expired CA1066853A (en) | 1975-09-08 | 1976-08-18 | Heart valve with arcuate occluder |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US4057857A (en) |
| JP (1) | JPS587294B2 (en) |
| CA (1) | CA1066853A (en) |
| DE (1) | DE2640246C3 (en) |
| FR (1) | FR2322580A1 (en) |
| GB (1) | GB1563617A (en) |
Families Citing this family (24)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4276132A (en) * | 1978-01-19 | 1981-06-30 | Shiley Incorporated | Electro-chemically machined ring and strut structure for prosthetic heart valves |
| DE2815756C3 (en) * | 1978-04-12 | 1982-01-28 | Ernst-Wilhelm 5303 Bornheim Müller | Prosthetic closure element to replace the valves in the human heart |
| US4183103A (en) * | 1978-06-29 | 1980-01-15 | Eric Bloch | Prosthetic one-way heart valve |
| US4240161A (en) * | 1979-02-21 | 1980-12-23 | Medical, Incorporated | Arcuate disc heart valve |
| US4343049A (en) * | 1979-03-08 | 1982-08-10 | Shiley, Inc. | Electro-chemically machined ring and strut structure for prosthetic heart valves |
| IT1116883B (en) * | 1979-06-13 | 1986-02-10 | Intonti Francesco | PERFECTION IN THE PROSTHESIS FOR CARDIAC VALMOLAPI SUBSTITUTIONS |
| US4308624A (en) * | 1979-08-07 | 1982-01-05 | Hemex, Inc. | Heart valve prosthesis |
| DE3165924D1 (en) * | 1980-03-27 | 1984-10-18 | Medtronic Inc | Pivoting disc heart valve |
| US4306319A (en) * | 1980-06-16 | 1981-12-22 | Robert L. Kaster | Heart valve with non-circular body |
| AR221550A1 (en) * | 1980-10-28 | 1981-02-13 | Bicer D | CARDIOVASCULAR VALVE PROSTHESIS AND MANUFACTURING PROCEDURE THEREOF |
| DE3380952D1 (en) * | 1982-09-07 | 1990-01-18 | Angicor Ltd | HEART VALVE PROSTHESIS WITH PLANCONVEXE CLOSING PART. |
| US4585453A (en) * | 1983-02-22 | 1986-04-29 | Shiley, Incorporated | Disposable holder for prosthetic heart valve |
| US4725275A (en) * | 1983-10-07 | 1988-02-16 | Peter Maroko | Artificial heart valve |
| US4661106A (en) * | 1983-10-07 | 1987-04-28 | Peter Maroko | Artificial heart valve |
| SU1243721A1 (en) * | 1984-02-16 | 1986-07-15 | Предприятие П/Я Р-6102 | Heart valve prosthesis |
| DE3442088A1 (en) * | 1984-11-17 | 1986-05-28 | Beiersdorf Ag, 2000 Hamburg | HEART VALVE PROSTHESIS |
| IN167706B (en) * | 1986-08-21 | 1990-12-08 | Sree Chitra Tirunal Inst For M | |
| EP0265533A1 (en) * | 1986-10-25 | 1988-05-04 | National Research Development Corporation of India | Heart valve assembly |
| SU1597184A1 (en) * | 1987-06-25 | 1990-10-07 | Предприятие П/Я Р-6102 | Heart valve prosthesis |
| EP0319593A4 (en) * | 1987-06-25 | 1990-04-10 | Bukatov Alexandr S | Heart valve prosthesis. |
| AU2124788A (en) * | 1987-07-02 | 1989-01-30 | Richard L. Martin | Heart valve with disc occluder |
| FR2642960B1 (en) * | 1989-02-15 | 1994-02-25 | Dassault Breguet Aviation | PROSTHETIC HEART VALVE |
| WO1998010719A1 (en) * | 1996-09-13 | 1998-03-19 | Medtronic, Inc. | Prosthetic heart valve with suturing member having non-uniform radial width |
| US7771478B2 (en) | 2003-04-04 | 2010-08-10 | Theken Spine, Llc | Artificial disc prosthesis |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3367364A (en) * | 1964-10-19 | 1968-02-06 | Univ Minnesota | Prosthetic heart valve |
| JPS4944517B1 (en) * | 1969-03-24 | 1974-11-28 | ||
| US3824629A (en) * | 1969-03-24 | 1974-07-23 | D Shiley | Pivoted discoid heart valve having a changing pivot axis |
| GB1327371A (en) * | 1969-05-21 | 1973-08-22 | Macleod N | Fluid control valves |
| US3926215A (en) * | 1973-08-03 | 1975-12-16 | Nat Res Dev | Fluid control valves |
| JPS4944517A (en) * | 1972-09-04 | 1974-04-26 |
-
1975
- 1975-09-08 US US05/611,273 patent/US4057857A/en not_active Expired - Lifetime
-
1976
- 1976-08-18 CA CA259,375A patent/CA1066853A/en not_active Expired
- 1976-09-03 JP JP51106186A patent/JPS587294B2/en not_active Expired
- 1976-09-07 DE DE2640246A patent/DE2640246C3/en not_active Expired
- 1976-09-07 FR FR7626929A patent/FR2322580A1/en active Granted
- 1976-09-07 GB GB36953/76A patent/GB1563617A/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPS587294B2 (en) | 1983-02-09 |
| DE2640246A1 (en) | 1977-03-17 |
| GB1563617A (en) | 1980-03-26 |
| FR2322580B1 (en) | 1982-10-22 |
| FR2322580A1 (en) | 1977-04-01 |
| JPS5234596A (en) | 1977-03-16 |
| US4057857A (en) | 1977-11-15 |
| DE2640246B2 (en) | 1981-06-25 |
| DE2640246C3 (en) | 1982-02-11 |
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