Stent and replacement heart valve prosthesis with improved fixation features
Disclosed is an improved stent and a related replacement heart valve prosthesis exhibiting various features for improved fixation and crush resistance. The stent is characterized by an inner stent fixed to an outer stent with connecting struts. The stent and heart valve prosthesis can be used for replacement of a defective endogenous heart valve.
1. A prosthesis comprising an outer stent that is a laser cut stent and an inner stent that is a laser cut stent, wherein:
(i) the outer stent comprises a proximal outer stent region and a distal outer stent region, wherein the distal outer stent region comprises a connecting strut guide;
(ii) the proximal outer stent region comprises a connecting strut and the inner stent comprises a connecting strut, wherein the connecting strut of the proximal outer stent region and/or the connecting strut of the inner stent is an S-strut;
(iii) the outer stent and the inner stent form a double layer that provides for crush resistance; and
(iv) the connecting strut of the inner stent and the connecting strut of the proximal outer stent region are connected by a connecting means, and
wherein, when implanted, the connecting strut guide is configured to slidably connect to the connecting strut of the inner stent, thereby connecting the inner stent, the proximal outer stent region, and the distal outer stent region in a proximal area of the prosthesis.
2. The prosthesis according to claim 1 , wherein the prosthesis comprises a proximal end, a middle area, and a distal end, and wherein:
a) the proximal end of the prosthesis has a longitudinal dimension of 1 to 25 mm, the middle area of the prosthesis has a longitudinal dimension of 1 to 25 mm, and the distal end of the prosthesis has a longitudinal dimension of 1 to 25 mm;
b) the proximal end, middle area, and distal end of the prosthesis have different outer diameters in an expanded state of the prosthesis;
c) the middle area of the prosthesis has a smaller outer diameter than an outer diameter of the proximal and distal ends of the prosthesis;
d) a radial force in a sub-annular area of the prosthesis is equal to or higher than a radial force in a ventricular or outflow area of the prosthesis; or
e) a radial force of an annular area and/or the distal area of the prosthesis is in a range of 0.5 to 20 N.
3. The prosthesis according to claim 2 , wherein:
a) the longitudinal dimension of the proximal area is from 1 to 5 mm, the longitudinal dimension of the middle area is from 4 to 10 mm, and the longitudinal dimension of the distal area is from 4 to 10 mm;
b) the outer diameter of the proximal, middle, and distal areas are in a range of 40 to 90 mm or 20 to 90 mm in the expanded state of the prosthesis; and/or
c) the middle area forms a groove.
4. The prosthesis of claim 1 , further comprising a valve fixed thereto, thereby forming a heart valve prosthesis.
5. The prosthesis according to claim 4 , wherein the valve is fixed to the prosthesis by one or more sutures.
6. The prosthesis according to claim 4 , wherein the inner stent:
a) has an inner diameter of between 8 mm and 40 mm;
b) has an outer diameter of between 15 mm and 41 mm; and/or
c) comprises an expanded configuration, wherein the inner stent has a longitudinal dimension of 8 to 35 mm in the expanded configuration.
7. The prosthesis according to claim 4 , wherein:
a) the outer stent forms an angle with the inner stent;
b) the outer stent is a nitinol stent;
c) the prosthesis can be crimped to a diameter of 16 to 40 French, 16 to 35 French, 20 to 35 French, or 25 to 35 French; and/or
d) the prosthesis is configured for deployment by way of catheter delivery.
8. The prosthesis according to claim 7 , wherein:
a) the angle formed by the outer stent with the inner stent is 5 to 90°, 25 to 50°, or 35 to 45°; and/or
b) the catheter delivery is transfemoral catheter delivery.
9. The prosthesis according to claim 7 , wherein:
a) the outer stent is characterized by 10 to 30 cells circumferentially in the proximal and/or distal area and/or the inner stent is characterized by 4 to 30, 4 to 24, or 10 to 30 cells circumferentially in three, four, or five rows.
10. The prosthesis according to claim 1 , wherein the connecting means is or comprises one or more sutures, a welding, one or more screws, or one or more clips.
11. The prosthesis according to claim 10 , wherein the one or more clips are characterized by an interlocking tooth and an interlocking yoke and a cover.
12. The prosthesis according to claim 1 , wherein the inner stent and the proximal outer stent region are connected with 4 to 24 combinations of connecting struts and connecting means and wherein the distal outer stent region comprises one connecting strut guide for each of the connecting struts of the inner stent.
13. The prosthesis according to claim 12 , wherein each of the inner stent and the proximal outer stent region comprises 6 to 14, 8 to 18, 8 to 12, or 12 of the connecting struts that are joined by the connecting means.
14. A method of replacement heart valve therapy comprising implanting the heart valve prosthesis according to claim 4 in a subject in need thereof.
15. The method of claim 14 , wherein the heart valve prosthesis is delivered using a catheter, wherein the method further comprises loading the heart valve prosthesis onto the catheter, introducing the catheter into the subject, moving the catheter to a target site, and deploying the heart valve prosthesis at the target site.
16. The method of claim 15 , wherein the heart valve prosthesis is delivered by transfemoral delivery.
17. The prosthesis of claim 1 , wherein the connecting means releasably joins the inner stent and the outer stent.
18. The prosthesis of claim 17 , wherein the connecting means comprises one or more sutures, a welding, one or more screws, or one or more clips.
19. The prosthesis of claim 1 , wherein the outer stent further comprises a middle area and a distal area, wherein the middle area and/or the distal area comprise a circumferential stabilizer positioned inside and/or outside the outer stent.
20. The prosthesis of claim 19 , wherein the circumferential stabilizer (i) is in a bent, zig-zag, or undulating geometry and/or (ii) is interwoven in the middle area of the outer stent and/or the distal area of the outer stent.