Value prosthesis for implantation in body channels

Claim 2

1 . A valve prosthesis for implantation in an aortic annulus, the valve prosthesis comprising: a collapsible, elastic valve member comprised of physiologically acceptable material, an elastic stent member in which said valve member is mounted, said stent member having internal and external surfaces, and a support coupled to the valve member and positioned between the valve member and the stent member, wherein said stent member forms a continuous surface and comprises strut members that provide a structure sufficiently rigid to prevent eversion, wherein the support extends from the internal surface of the stent member to the external surface of the stent member, and wherein the stent member has sufficient radial and longitudinal rigidity to withstand the radial force necessary for implantation, to resist aortic recoil forces, and to provide long-term support to the valve structure.

Claim 3

2 . The valve prosthesis of claim 1 , wherein the valve member has a substantially truncated hyperboidal shape.

Claim 4

3 . The valve prosthesis of claim 1 wherein the valvular structure and/or the support are coated with, are made of, or are treated with an anti-thrombotic substance.

Claim 5

4 . The valve prosthesis of claim 3 , where the valvular structure and/or the support are treated with an anti-thrombotic substance.

Claim 6

5 . The valve prosthesis of claim 1 , wherein the valve member tissue is a synthetic biocompatible material or a biological material.

Claim 7

6 . The valve prosthesis of claim 5 , wherein the synthetic biocompatible material is polyurethane, polyethylene, or polyamide, or a co-polymer thereof.

Claim 8

7 . The valve prosthesis of claim 5 , wherein the biological material is pericardium, bovine or porcine leaflets.

Claim 9

8 . The valve prosthesis of claim 1 , wherein the valve member is fastened to the stent member by sewing, by molding, soldering or by gluing, to prevent regurgitation of said body fluid between the stent member and the valve member.

Claim 10

9 . The valve prosthesis of claim 1 , wherein the stent member is expandable from a size of from about 4 to 5 millimeters to a size of from about 20 to 35 mm in diameter.

Claim 11

10 . The valve prosthesis of claim 1 , wherein the stent member is made of a material which is distinguishable from biological tissue by non-invasive imaging techniques.

Claim 12

11 . The valve prosthesis of claim 1 , wherein the stent member is a foldable plastic or stainless metal structure made of intercrossing, linear bars.

Claim 13

12 . The valve prosthesis of claim 11 , wherein the size and number of the bars (1) provide sufficient radial rigidity to prevent significant recoil when the stent member is in its expanded state and (2) facilitate introduction of the valve prosthesis by a minimally invasive vascular procedure.

Claim 14

13 . The valve prosthesis of claim 12 , wherein the size and number of the bars are determined to give maximal rigidity when the stent member is in its expanded state.

Claim 15

14 . The valve prosthesis of claim 12 , wherein the size and number of the bars give the valve prosthesis the smallest volume when the stent member is in its compressed state.

Claim 16

15 . The valve prosthesis of claim 1 , wherein the stent member has a concave shape comprising projecting curved bars at the extremities.

Claim 17

16 . A method of implanting a valve prosthesis, which comprises the steps of: (a) advancing a first balloon dilatation catheter having distal and proximal ends and having a deflated first dilatation balloon adjacent the catheter distal end into a patient's vasculature to position said first dilatation balloon within to a stenotic aortic valve and annulus; (b) inflating said first dilatation balloon to dilate the stenotic aortic valve; (c) deflating said first dilatation balloon and withdrawing said deflated balloon in the proximal direction; (d) advancing a second dilatation catheter having distal and proximal ends and having a second deflated dilatation balloon adjacent the catheter distal end, wherein said second balloon has a valve prosthesis arranged circumferentially around said second dilatation balloon, into the patient's vasculature to position said second dilatation balloon and said valve prosthesis adjacent to the previously dilated stenotic aortic valve; (e) inflating said second dilatation balloon to cause said valve prosthesis to adhere to said aortic valve and annulus; and (f) deflating said second dilatation balloon and withdrawing said second catheter in the proximal direction.

Claim 18

16 . A method of implanting a valve prosthesis, which comprises the steps of: (a) advancing a first balloon dilatation catheter having distal and proximal ends and having a deflated first dilatation balloon adjacent the catheter distal end into a patient's vasculature to position said first dilatation balloon within to a stenotic aortic valve and annulus; (b) inflating said first dilatation balloon to dilate the stenotic aortic valve; (c) deflating said first dilatation balloon and withdrawing said deflated balloon in the proximal direction; (d) advancing a second dilatation catheter having distal and proximal ends and having a second deflated dilatation balloon adjacent the catheter distal end, wherein said second balloon has a valve prosthesis arranged circumferentially around said second dilatation balloon, into the patient's vasculature to position said second dilatation balloon and said valve prosthesis adjacent to the previously dilated stenotic aortic valve; (e) inflating said second dilatation balloon to cause said valve prosthesis to adhere to said aortic valve and annulus; and (f) deflating said second dilatation balloon and withdrawing said second catheter in the proximal direction.

Claim 19

17 . The method of claim 16 , wherein prior to step (a), a guidewire having a distal end is advanced distally into the patient's vasculature until the guidewire distal end is adjacent or distal to the stenotic aortic valve.

Claim 20

18 . The method of claim 17 , wherein in steps (a) and (d) the first and second balloon catheters, respectively, are advanced over the guidewire.

Claim 21

19 . The method of claim 16 , wherein in step (b) the first dilatation balloon is inflated to a high pressure.

Claim 22

20 . The method of claim 19 , wherein the pressure is greater than 4 atm.

Claim 23

21 . The method of claim 19 , wherein the first dilatation balloon is inflated maximally up to the balloon's bursting point.

Claim 24

22 . The method of claim 19 , wherein the inflation lasts only a few seconds.

Claim 25

23 . The method of claim 16 , wherein inflating the dilatation balloon in step (b) tests the stenotic aortic valve for efficacy of the procedure and creates an aperture in the valve.

Claim 26

24 . The method of claim 16 , wherein in step (e) the second dilatation balloon is inflated to a high pressure.

Claim 27

25 . The method of claim 24 , wherein the second dilatation balloon is inflated to a pressure less than the pressure to which the first dilatation balloon is inflated.

Claim 28

26 . The method of claim 24 , wherein the pressure is less than 4 atm and does not damage the valve prosthesis.

Claim 29

27 . The method of claim 24 , wherein the inflation lasts only a few seconds.

Claim 30

28 . The method of claim 16 , wherein the valve prosthesis needs only a light pressure for its own expansion.

Claim 31

29 . The method of claim 16 , wherein the valve prosthesis is the valve prosthesis of claim 1.