APPARATUS AND METHODS FOR RECANNALIZATION, VALVE REPAIR AND REPLACEMENT

• US 20150216552A1
• Filed: 02/02/2015
• Published: 08/06/2015
• Est. Priority Date: 02/02/2014
• Status: Active Grant

• Current Assignee: Gil Hefer
• Original Assignee: Gil Hefer
• Inventors: Hefer, Gil
• Granted Patent: US 9,724,121 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 17/320725 with radially expandable cutting or abrading elements A61B17/32075 takes precedence
• CPC Class Codes: A61B 2017/22061 for spreading elements apart
• CPC Class Codes: A61B 2017/22098 Decalcification of valves
• CPC Class Codes: A61M 2025/109 having balloons for removing solid matters, e.g. by grasping or scraping plaque, thrombus or other matters that obstruct the flow
• CPC Class Codes: A61M 2025/1097 with perfusion means for enabling blood circulation only while the balloon is in an inflated state, e.g. temporary by-pass within balloon
• CPC Class Codes: A61M 25/104 used for angioplasty
• CPC Class Codes: A61M 29/02 Dilators made of swellable material balloon catheters for angioplasty A61M25/104

Abstract

A scaffold is mounted on a balloon of a balloon catheter. The scaffold has closed cells which deform upon balloon expansion and generate forces that cause struts or other components of the scaffold to deflect outwardly to a diameter that is greater than the inflated diameter balloon. The deflected struts apply forces to fracture plaque of other hardened lesions and also form an annular gap surrounding the balloon to provide for bypass flow of blood or other body fluids. A sheath may be located over the deflected struts to protect adjacent tissue structures from the deflected struts and/or to further define the gap.

Claims

1. A scaffold comprising:

a tubular body configured to be carried over a balloon on a balloon catheter, said body including a plurality of deformable closed cells arranged in axial columns and circumferential rings, wherein axially adjacent cells are connected at axial connection points and circumferentially adjacent cells are connected at circumferential connection points; and

deformable struts extending between the axial connection points within at least some of the deformable cells and configured so that a mid-portion of the strut deflects radially outwardly as the cell axially shortens as the tubular body is radially expanded by the balloon.

2. A scaffold as in claim 1, wherein the deformable struts are distributed uniformly over one or more circumferential regions of the tubular body.

3. A scaffold as in claim 1, wherein the deformable struts are distributed uniformly over one or more axial regions of the tubular body.

4. A scaffold as in claim 1, wherein the deformable struts are distributed uniformly over the entire tubular body.

5. A scaffold as in claim 1, wherein the cells in one or more circumferential regions of the tubular body do not have the deformable struts therein.

6. A scaffold as in claim 1, wherein the cells in a first circumferential region of a first end of the tubular body and in a second circumferential region of a second end of the tubular body do not have the deformable struts therein.

7. A scaffold as in claim 1, wherein the cells are diamond-shaped.

8. A scaffold as in claim 1, wherein the cells are defined by adjacent separate rings.

9. A scaffold as in claim 1, wherein the cells are defined by adjacent zig-zag rings.

10. A scaffold as in claim 1, wherein the mid-portion of the deformable strut includes a force distribution pad.

11. A scaffold as in claim 10, wherein the force distribution pad comprises an open frame.

12. A scaffold as in claim 11, wherein the open frame is rectangular or circular.

13. A scaffold as in claim 10, wherein the ends of the deformable strut which are attached to the axial connection points are bifurcated.

14. A scaffold as in claim 10, wherein the mid-portion is biased to open radially outwardly as the strut is axially compressed by the axial shortening of the cell.

15. A scaffold as in claim 14, wherein the open frame comprises a first circumferentially oriented beam attached to an inner end of a first segment of the deformable strut and a second circumferentially oriented beam attached to an inner end of a second segment of the deformable strut, wherein remote ends of each deformable strut segment are attached to the axial attachment points of the cell and wherein each circumferentially oriented beam torques about its axis as the tubular body is radially expanded by the balloon and the deformable strut deflects radially outwardly.

16. A scaffold as in claim 1, further comprising a sheath disposed coaxially over at least a portion of the tubular body.

17. An assembly comprising

a scaffold as in claim 1;

a balloon catheter having proximal and distal ends and a balloon disposed near the distal end thereof, wherein the scaffold is disposed over the balloon.

18. An assembly as in claim 17, further comprising a sheath disposed coaxially over scaffold and attached to the catheter at locations distal to the balloon and proximal to the balloon.

19. An assembly as in claim 18, wherein the strut has inlet flow ports at a distal end thereof and outlet flow ports at a proximal end thereof wherein the inlet flow ports are aligned with an annular flow region defined between the balloon and sheath by the deflected deformable struts when the balloon is expanded and wherein the outlet flow ports are blocked by the balloon when the balloon is expanded, wherein blood flow in a direction from the inlet flow ports to the outlet flow ports can occur but blood flows in a direction from the outlet flow ports to the inlet flow ports is blocked.

20. A method for fracturing a vascular calcification, said method comprising providing a balloon catheter having a balloon which carries a radically expandable scaffold;

positioning the balloon catheter in a patient'"'"'s vasculature so that the scaffold is within the vascular calcification;

inflating the balloon to radially expand the scaffold, wherein radial expansion of the scaffold deflects a plurality of calcification-engaging elements radially outwardly from the scaffold to engage and fracturing the calcification.

21. A method as in claim 20, wherein the calcification is located on the wall of a blood vessel.

22. A method as in claim 20, wherein the calcification is present in a valve.

23. A method as in claim 20, wherein a sheath is disposed over the scaffold so that the sheath provides an interface between calcification-engaging elements and the calcification, wherein said sheath inhibits the elements from penetrating the blood vessel wall.

24. A method as in claim 20, wherein the sheath includes inlet flow ports and outlet flow ports which are configured to provide blood flow through the sheath.

25. A method as in claim 20, wherein the ports are further configured to provide blood flow in one direction only.