METHODS AND APPARATUS FOR PERCUTANEOUS AORTIC VALVE REPLACEMENT

• US 20090030510A1
• Filed: 07/25/2008
• Published: 01/29/2009
• Est. Priority Date: 07/23/2007
• Status: Active Grant

• Current Assignee: Hocor Cardiovascular Technologies, LLC
• Original Assignee: Hocor Cardiovascular Technologies, LLC
• Inventors: Ho, Paul C.
• Granted Patent: US 8,663,319 B2
• Time in Patent Office: Days
• US Class Current: 623/2.110
• CPC Class Codes: A61B 17/12036 partial occlusion
• CPC Class Codes: A61B 17/1204 temporary occlusion
• CPC Class Codes: A61B 17/12109 in a blood vessel
• CPC Class Codes: A61B 17/12122 within the heart for closing a cardiac septal defect A61B17/0057
• CPC Class Codes: A61B 17/12136 Balloons
• CPC Class Codes: A61B 2017/00703 correcting for movement of heart, e.g. ECG-triggered
• CPC Class Codes: A61F 2/2418 Scaffolds therefor, e.g. support stents
• CPC Class Codes: A61F 2/2433 using balloon catheter
• CPC Class Codes: A61F 2250/0059 temporary
• CPC Class Codes: A61F 2250/006 modular

Abstract

A delivery system and method for percutaneous aortic valve (PAV) replacement and apparatus used therein. A temporary aortic valve comprised of a reversibly expandable occluding means, such as balloons, surrounds a central catheter mechanism. The temporary valve is positioned within the ascending aorta, just above and downstream from the coronary ostia. The occluding means is configured such that, when fully expanded against the aortic wall, gaps are left that promote continuous coronary perfusion during the cardiac cycle. The temporary valve with occluding means substitutes for the function of the native aortic valve during its replacement. The native aortic valve is next dilated, and then ablated through deployment of low profile, elongated, sequentially delivered stents. The ablation stent(s) displace the native valve tissues and remain within the aortic annulus to receive and provide a structure for retaining the PAV. The PAV is delivered, positioned and deployed within the ablation stent(s) at the aortic annulus with precision and relative ease. Ablation of the native aortic valve removes the structural obstacles to precise PAV placement. The temporary aortic valve mediates the hemodynamic forces upon the devices as encountered by the surgeon following native valve ablation. The temporary valve also promotes patient stability through continuous coronary perfusion and a moderated transvalvular pressure gradient and regurgitation. Sequential delivery of low profile PAV components minimize the risk of trauma and injury to vascular tissues. Mathematical considerations for determining the optimum cross-sectional area for the temporary valve blood perfusion gaps are also described.

Claims

1. A method for percutaneous aortic valve replacement comprising ablating the native aortic valve with a percutaneously introduced ablation means, said ablation means remaining within the aortic annulus and forming the infrastructure to receive and house a replacement tissue valve.

2. The method of claim 1 wherein a temporary aortic valve is deployed within the ascending aorta prior to ablation of the native aortic valve.

3. The method of claim 2 wherein the native aortic valve is pre-dilated prior to deployment of the temporary aortic valve.

4. The method of claim 2 wherein the native aortic valve is pre-dilated following deployment of the temporary aortic valve and prior to ablation of the native aortic valve.

5. The method of claim 1 wherein said ablation means comprises a low profile stent.

6. The method of claim 1 wherein said ablation means comprises a plurality of low-profile stents sequentially delivered and concentrically deployed one within the other.

7. The method of claim 6, wherein the number of concentrically deployed low-profile stents ranges from 1 to 3.

8. The method of claim 1 wherein said ablation stent is advanced into position within the aortic annulus in elongated form and foreshortens during deployment.

9. The method of claim 1 wherein the ablation means and replacement aortic valve are deployed through a central catheter mechanism having a diameter within the range of 8 to 12 French.

10. The method of claim 1 wherein the ablation means and replacement aortic valve are deployed through a central catheter mechanism having a diameter within the range of 12 to 18 French.

11. The method of claim 1 wherein the ablation means and replacement aortic valve are deployed through a central catheter mechanism having a diameter within the range of 8 to 18 French.

12. The method of claim 1 wherein said ablation means is balloon mounted and deployed within the aortic annulus to ablate the native aortic valve by inflation of said balloon.

13. The method of claim 1 wherein said replacement aortic valve is a low-profile tissue valve with compact frame deployed within and secured by said ablation means.

14. The method of claim 5 wherein said low-profile ablation stent is fabricated from high strength composite material.

15. The method of claim 13 wherein said low-profile replacement tissue valve is framed using high strength composite material.

16. The method of claim 1, wherein said ablation means has drug-elution capabilities.

17. A replacement aortic valve used in percutaneous aortic valve replacement procedures comprising

a plurality of low-profile stents sequentially delivered and concentrically deployed within the aortic annulus;

and

a low profile tissue valve with compact frame deployed within and housed by said low-profile stents.

18. The replacement valve of claim 17, wherein said low profile stents serve to ablate the native aortic valve and prepare the aortic annulus for the tissue valve.

19. The replacement valve of claim 17, wherein the low-profile stents are delivered to the aortic annulus in elongated form and foresthorten during deployment.

20. The replacement valve of claim for 17 wherein said low-profile stents and frame of said tissue valve are fabricated from high strength composite materials.