Clot retrieval devices

Patent metadata

Field	Value
Publication number	US-9433429-B2
Application number	US-201313829684-A
Country	US
Kind code	B2
Filing date	Mar 14, 2013
Priority date	Mar 14, 2013
Publication date	Sep 6, 2016
Grant date	Sep 6, 2016

Abstract

A self-expandable mechanical clot retrieval device is designed variously to dislodge, engage and retract blood clot from extremely small and tortuous vasculature. The retrieval device comprises an elongate member and a plurality of ring elements. The ring elements may comprise a plurality of struts and crowns interconnected by a tether formed at a distal end of the elongate member or may be a separate component attached thereto. At least one tether may connect each ring element to the elongate member to restrain the ring element in a collapsed configuration during delivery of the retrieval device through an intravascular microcatheter. The tether connecting the ring element to the elongate member disengages when the retrieval device is positioned at the occluded site and the microcatheter is retracted to allow the self-expandable ring elements to reach an expanded configuration.

First claim

The invention claimed is:

1. A clot retrieval device comprising:
an elongate member and a plurality of clot engaging elements at a distal end of the elongate member, the clot engaging elements being self expandable between a retracted delivery configuration and an expanded deployed configuration; and
a plurality of restraining rings, each restraining ring positioned adjacent a clot engaging element of the plurality of clot engaging elements and including a restraining portion having a radially inner surface sized to receive a proximally extending tab of a clot engaging element of the plurality of clot engaging elements for biasing the clot engaging element in a retracted delivery configuration against the elongate member, wherein one restraining ring of the plurality of restraining rings is positioned proximally of each of the plurality of clot engaging elements in both the retracted delivery configuration and the expanded deployed configuration; and
wherein each restraining ring is releasable from an adjacent clot engaging element to allow the clot engaging element to expand into the deployed configuration.

2. A device as claimed in claim 1 wherein the elongate member extends exterior of the patient in use.

3. A device as claimed in claim 1 wherein the diameter of the clot engaging elements in the expanded deployed configuration is greater than the diameter of the clot engaging elements in the retracted delivery configuration.

4. A device as claimed in claim 1 wherein each of the plurality of restraining rings is connected to either the clot engagement elements, the elongate member, or to both.

5. A device as claimed in claim 1 wherein the each of the plurality of restraining rings includes a collar, an interior circumferential surface including the radially inner surface.

6. A device as claimed in claim 5 wherein the clot engagement elements comprise a plurality of struts and said plurality of restraining rings are configured to limit relative movement between at least a pair of said struts.

7. A device as claimed in claim 5 wherein the plurality of restraining rings are configured to limit relative movement between the clot engagement elements and the elongate member.

8. A device as claimed in claim 1 wherein the elongate member is configured to activate the plurality of restraining rings.

9. A device as claimed in claim 1 , wherein the tab includes a bevel.

10. A clot retrieval device comprising:
an elongate member, a first clot engaging element and a second clot engaging element, the first clot engaging element distal of the second clot engaging element, the clot engaging elements being self expandable and having a sheathed delivery configuration, a deployed configuration, and a fully expanded configuration; and
at least one restraining ring having a restraining portion with a radially inner surface sized to receive a tab extending proximally from the first clot engaging element for biasing the first clot engaging element in the deployed configuration, wherein the radially inner surface abuts the tab in the deployed configuration;
wherein activation of the at least one restraining ring allows the first clot engaging element to expand into the fully expanded configuration.

11. A device as claimed in claim 10 wherein the sheathed delivery configuration comprises sheathing within the lumen of a microcatheter.

12. A device as claimed in claim 11 wherein unsheathing the clot engaging elements allows the first and second clot engaging elements to expand to the deployed configuration.

13. A device as claimed in claim 12 wherein the diameter of the first and second clot engaging elements in the deployed configuration is greater than the diameter of the first and second clot engaging elements in the sheathed delivery configuration.

14. A device as claimed in claim 10 wherein the at least one restraining ring is axially moveable relative to the first and second clot engaging elements.

15. A device as claimed in claim 10 wherein the at least one restraining ring is connected to either the clot engagement elements, the elongate member, or to both.

16. A device as claimed in claim 10 wherein the at least one restraining ring includes a collar.

17. A device as claimed in claim 10 wherein the elongate member is configured to activate the at least one restraining ring.

18. A device as claimed in claim 10 , wherein the restraining ring is coupled to and longitudinally fixed relative to the elongate member.

19. A device as claimed in claim 10 , wherein the clot engagement element includes a sinusoidally shaped strut ring.

20. A device as claimed in claim 10 , wherein the tab includes a bevel.

21. A clot retrieval device comprising:
an elongate member and at least one clot engaging element at a distal end of the elongate member, the clot engaging element being self expandable between a retracted delivery configuration, a deployed configuration, and a fully expanded configuration; and
a restraining ring including a restraining portion having a radially inner surface sized to receive a tab extending from the clot engaging element when the clot engaging element is in the retracted delivery configuration, and wherein the radially inner surface abuts the tab in the retracted delivery configuration,
wherein the restraining ring includes at least one collar movable relative to the clot engaging element; and wherein proximal movement of the restraining ring allows the at least one clot engaging element to expand from the deployed configuration to the fully expanded configuration.

22. A device as claimed in claim 21 , wherein the restraining ring is coupled to the elongate member, and the radially inner surface of the restraining portion is located in or along one of a recess, hole, or groove.

23. A device as claimed in claim 21 , further including a plurality of restraining rings and a plurality of clot engagement elements, each restraining ring being associated with a clot engagement element.

24. A device as claimed in claim 23 , wherein the plurality of restraining rings and the plurality of clot engaging elements are aligned alternatingly along the elongate member.

25. A device as claimed in claim 21 , wherein the clot engagement element includes a strut ring.

26. A device as claimed in claim 25 , wherein the strut ring is sinusoidally shaped.

27. A device as claimed in claim 21 , wherein the restraining ring is coupled to and longitudinally fixed relative to the elongate member.

28. A device as claimed in claim 21 , wherein the restraining ring is positioned proximally of the clot engaging element in both the retracted delivery configuration and the expanded deployed configuration.

29. A device as claimed in claim 21 , wherein the tab is a proximally extending tab.

30. A device as claimed in claim 21 , wherein the tab includes a bevel.

Assignees

• Vale David
• Brady Eamon
• Gilvarry Michael
• Ravazi Mahmood
• Neuravi Ltd

Inventors

• Vale David
• Brady Eamon
• Gilvarry Michael
• Ravazi Mahmood

Classifications

• A61B2017/2215

  having an open distal end · CPC title

• A61B2017/22034

  for gripping the obstruction or the tissue part from inside · CPC title

• A61B2017/22094

  for crossing total occlusions, i.e. piercing · CPC title

• A61B17/221 Primary

  Gripping devices in the form of loops or baskets {for gripping calculi or similar types of obstructions (surgical snare instruments A61B17/32056)} · CPC title

• A61B2017/22061

  for spreading elements apart · CPC title