Suture rings for rotatable artificial heart valves

Claim 2

An artificial heart valve having a controlled resistance to torque, comprising: an annular valve body having opposite longitudinal ends, a blood flow passageway therethrough, and an outer surface; a suture ring mounted on the outer surface of the valve body to be relatively rotatable therewith, the suture ring including an inner surface, an outer surface, a proximal edge, and a distal edge; a needle-penetrable sheet being interposed between the inner surface of the suture ring and the outer surface of the valve, the sheet having a thickness; and at least one protuberance formed on either the outer surface of the valve body or the inner surface of the suture ring for compressing the sheet therebetween, a majority of the sheet interposed between the inner surface of the suture ring and the outer surface of the valve otherwise being uncompressed, the protuberance having a height forming a gap between the inner surface of the suture ring and the outer surface of the valve body, the height of the protuberance and thus the size of the gap being dependent on the thickness of the sheet so that the torque required to rotate the valve body with respect to the suture ring is maintained within a range having a minimum above that at which the valve body would freely rotate within the suture ring and a maximum below that which would require excessive force to turn the valve body within the suture ring.

Claim 3

The valve of claim 1, wherein the protruberance is formed circumferentially around the outer surface of the valve body or the inner surface of the suture ring.

Claim 4

The valve of claim 2, wherein the protruberance is an annular rib.

Claim 5

The valve of claim 3, wherein there are two annular ribs of equal height.

Claim 6

The valve of claim 1, wherein the sheet is a fabric having a thickness of between 0.008 inch and 0.014 inch.

Claim 7

The valve of claim 1, wherein the sheet is a fabric and the suture ring comprises a ring member and a surrounding sponge member, the fabric sheet extending around the suture ring and around the proximal and distal edges thereof to pass inbetween the suture ring and valve body at both longitudinal ends.

Claim 8

The valve of claim 6, wherein the fabric sheet is a single piece.

Claim 9

The valve of claim 6, wherein the ring member is a polyacetal and the protruberance comprises a pair of annular ribs projecting inwardly therefrom.

Claim 10

An artificial heart valve having a controlled resistance to torque, comprising: an annular valve body having opposite longitudinal ends, a blood flow passageway therethrough, and a rigid outer surface; a suture ring mounted on the outer surface of the valve body to be relatively rotatable therewith, the suture ring including a generally rigid inner surface, an outer surface, a proximal edge, and a distal edge; a needle-penetrable sheet being interposed between the inner surface of the suture ring and the outer surface of the valve body, the sheet having a longitudinal dimension extending between the inner surface of the suture ring and the outer surface of the valve body, the sheet being compressed within a gap formed between the generally rigid inner surface of the suture ring and the rigid outer surface of the valve body to substantially determine the torque required to rotate the valve body with respect to the suture ring, the sheet extending into voids along most of its longitudinal dimension, the voids defined intermediate the inner surface of the suture ring and the outer surface of the valve body, and the sheet not being compressed in the voids so that the torque required to rotate the valve body with respect to the suture ring is maintained within a range having a minimum above that at which the valve body would freely rotate within the suture ring and a maximum below that which would require excessive force to turn the valve body within the suture ring.

Claim 11

An artificial heart valve having a controlled resistance to torque, comprising: an annular valve body having opposite longitudinal ends, a blood flow passageway therethrough, and a rigid outer surface; a suture ring mounted on the outer surface of the valve body to be relatively rotatable therewith, the suture ring including a generally rigid inner surface, an outer surface, a proximal edge, and a distal edge; a needle-penetrable sheet being interposed between the inner surface of the suture ring and the outer surface of the valve body, the sheet having a longitudinal dimension extending between the inner surface of the suture ring and the outer surface of the valve body, the sheet being compressed within a gap formed between the generally rigid inner surface of the suture ring and the rigid outer surface of the valve body to substantially determine the torque required to rotate the valve body with respect to the suture ring, the sheet extending into voids along most of its longitudinal dimension, the voids defined intermediate the inner surface of the suture ring and the outer surface of the valve body, and the sheet not being compressed in the voids so that the torque required to rotate the valve body with respect to the suture ring is maintained within a range having a minimum above that at which the valve body would freely rotate within the suture ring and a maximum below that which would require excessive force to turn the valve body within the suture ring.

Claim 12

The valve of claim 9, wherein the sheet is a fabric and the suture ring comprises a ring member and a surrounding sponge member, the fabric sheet extending around the suture ring and around the proximal and distal edges thereof to pass inbetween the suture ring and valve body at both longitudinal ends.

Claim 13

The valve of claim 10, wherein the fabric sheet is a single piece.

Claim 14

The valve of claim 9, wherein the suture ring includes a pair of annular ribs projecting inwardly therefrom which contact and compress the fabric sheet against the valve body.

Claim 15

The valve of claim 12, wherein the two annular ribs are of equal height.

Claim 16

The valve of claim 12, wherein the sheet is a fabric and has a thickness of between 0.008 inch and 0.014 inch and the height of the annular ribs is dependent on the thickness of the sheet.