Thrombus removal system and process

• US 7,955,344 B2
• Filed: 04/01/2005
• Issued: 06/07/2011
• Est. Priority Date: 04/01/2005
• Status: Active Grant

• Current Assignee: Nexgen Medical Systems, Inc.
• Original Assignee: Nexgen Medical Systems, Inc.
• Inventors: Finitsis, Stephanos
• Primary Examiner(s): Nguyen; Anhtuan T
• Assistant Examiner(s): EASTWOOD, DAVID C
• Application Number:
  US11/097,354
• Publication Number:
  US 20060224177A1
• Time in Patent Office: 2,258 Days
• Field of Search: 606/200, 606/127, 606/113, 606/159, 606/192
• US Class Current: 606/159
• CPC Class Codes: A61B 17/221 Gripping devices in the form of loops or baskets for gripping calculi or similar types of obstructions surgical snare instruments A61B17/32056
• CPC Class Codes: A61B 17/32056 Surgical snare instruments for removing or smashing calculi A61B2017/2212; tonsillotomes A61B17/26
• CPC Class Codes: A61B 17/3207 Atherectomy devices working by cutting or abrading; Similar devices specially adapted for non-vascular obstructions A61B17/32037 takes precedence; endoscopic cutting instruments A61B17/320016
• CPC Class Codes: A61B 2017/2212 having a closed distal end, e.g. a loop

Abstract

A device captures and assists in the removal of a thrombus in arteries, even in small arteries. The device uses a soft coil mesh to engage the surface of a thrombus, and a guidewire is used to retract the soft coil mesh with the captured thrombus. The soft coil is formed by an elongated microcoil element that forms the helical elements of a macrocoil element. The microcoil element provides a relatively elastic effect to the helical element forming the macrocoil and allows for control of gripping forces on the thrombus while reducing non-rigid contact of the device with arterial walls.

Claims

1. A method of capturing and retrieving a thrombus within vasculature of a living organism comprising:

inserting into the vasculature a medical device comprising;

a macrocoil having a first set of loops therein in a thrombus engaging component having a length with a proximal end and a distal end, the length of the macrocoil comprising microcoils having a second set of loops therein that allow the length of the macrocoil and the microcoils to be extendable;

a first wire capable of providing force on the distal end of the macrocoil;

a second wire capable of providing force on the proximal end of the macrocoil;

the macrocoil loops retracting to a size fitting into a catheter having a diameter of about 1 mm or less when in the lumen, and the microcoil expanding to a width of at least twice the size of the macrocoil loops in the catheter when removed from the lumen and distended by relative movement between the first wire and second wire;

positioning at least a portion of the macrocoil past a thrombus;

adjusting the position of section of the macrocoil with respect to the thrombus by movement of at least one of the first wire and second wire to alter dimensions on both the first set of loops in the macrocoil and the dimensions of the second set of loops in the microcoils;

entraining the thrombus within coils of the macrocoil by movement of at least one of the first wire and second wire exerting force on the macrocoil and the microcoils to extend the macrocoil and the microcoils; and

removing the thrombus by withdrawing the medical device from the vasculature.

3. A method of capturing and retrieving a thrombus within vasculature of a living organism according to claim 1, further comprising:

providing force with the first wire on the distal end of the macrocoil and extending both the macrocoil and the microcoils and further extending microcoils by applying force through the second wire and entraining the thrombus with extended macrocoil and extended microcoils.

4. The method of claim 1 wherein the macrocoil and first and second wire are carried to a position adjacent the thrombus in a catheter having an exterior diameter with no portion of the macrocoil being expanded beyond the exterior diameter of the catheter.

6. The method of claim 3 wherein the macrocoil and first and second wire are carried to a position adjacent the thrombus in a catheter having an exterior diameter with no portion of the macrocoil being expanded beyond the exterior diameter of the catheter.

13. The method of claim 1 wherein the first wire and the second wire are linear and forces applied through the first and second wires are transmitted through a straight first wire and a straight second wire.

15. The method of claim 3 wherein the first wire and the second wire are linear and forces applied through the first and second wires are transmitted through a straight first wire and a straight second wire.

17. The method of claim 1 wherein the first wire is attached to a first end of the macrocoil and the second wire being attached to a second end of the macrocoil, and opposed separating movement between the first wire and the second wire extends loops in the macrocoil and extends loops in the microcoils.

2. A method of capturing and retrieving a thrombus within vasculature of a living organism comprising:

inserting into the vasculature a medical device comprising;

a macrocoil in a thrombectomy catheter lumen, the macrocoil having a first set of loops therein in a thrombus engaging component having a length with a proximal end and a distal end, the length of the macrocoil comprising microcoils having a second set of loops therein that allow the length of both the macrocoil and the microcoils to be extendable;

a first wire capable of providing force on the distal end of the macrocoil;

a second wire capable of providing force on the proximal end of the macrocoil;

the loops of the macrocoil retracting to a maximum thickness of less than that of a thrombectomy catheter lumen when within the thrombectomy catheter lumen, and the loops of the microcoil expanding to a width of at least twice that of the thrombectomy catheter lumen when distended by relative movement between the first wire and second wire and wherein the macrocoil and the microcoil comprise non-thrombogenic compositions;

positioning at least a portion of the macrocoil past a thrombus;

adjusting the position of section of the macrocoil with respect to the thrombus by movement of at least one of the first wire and second wire to alter dimensions on the loops of both the first set of loops in the macrocoil and the dimensions of the second set of loops in the microcoils so that the loops of the microcoil are at least twice the thickness of the thrombectomy catheter lumen;

entraining the thrombus within coils of the macrocoil by movement of at least one of the first wire and second wire exerting force on the macrocoil and the microcoils; and

removing the thrombus by withdrawing the medical device from the vasculature.

5. The method of claim 2 wherein the macrocoil and first and second wire are carried to a position adjacent the thrombus in a catheter having an exterior diameter with no portion of the macrocoil being expanded beyond the exterior diameter of the catheter.

14. The method of claim 2 wherein the first wire and the second wire are linear and forces applied through the first and second wires are transmitted through a straight first wire and a straight second wire.

18. The method of claim 2 wherein the first wire is attached to a first end of the macrocoil and the second wire being attached to a second end of the macrocoil, and opposed separating movement between the first wire and the second wire extends loops in the macrocoil and extends loops in the microcoils.

7. A method for removing clots from a blood vessel, comprising the steps of:

providing a clot pulling device comprising a medical device within a thrombectomy catheter lumen having a catheter lumen diameter of about 1 mm or less, the medical device comprising;

a macrocoil in a thrombectomy catheter lumen, the macrocoil being a single wire having a first set of loops therein in a thrombus engaging component having a length with a proximal end and a distal end, the length of the macrocoil comprising microcoils in the single wire having a second set of loops in the thrombus engaging component therein that allow the length of the macrocoil and the length of the microcoils to be extendable;

a first wire capable of providing force on the distal end of the macrocoil;

a second wire capable of providing force on the proximal end of the macrocoil;

the macrocoil retracting to a maximum thickness of less than 1 mm when within the thrombectomy catheter lumen, and the microcoil expanding to a width of at least twice that of the thrombectomy catheter lumen when removed from the thrombectomy catheter lumen and distended by relative movement between the first wire and second wire;

having a pushing member coupled to the proximal end or distal end of the macrocoil proximally therefrom, providing the medical device within a catheter having a lumen extending therethrough;

advancing the catheter through a blood vessel to a location adjacent an area of interest;

advancing at least a portion of the macrocoil through the lumen of the catheter to a position distal of the area of interest;

expanding the macrocoil by altering dimensions on the first set of loops in the macrocoil; and

entrapping a clot within the basket by applying force on the macrocoil and microcoils and altering dimensions of the loops of both the macrocoil and the microcoils.

8. The method of claim 7 wherein the macrocoil is carried to a position adjacent the thrombus in a catheter having an exterior diameter with no portion of the macrocoil being expanded beyond the exterior diameter of the catheter.

9. The method of claim 8 wherein a first and second wire attached to the macrocoil is also carried within the catheter to the position adjacent to the thrombus.

10. The method of claim 9 wherein at least one of the first and second wire is used to deploy the macrocoil from the catheter to assist in engaging the thrombus with the macrocoil.

11. The method of claim 7 wherein the catheter is positioned within a blood vessel within the brain adjacent the thrombus.

12. The method of claim 7 wherein the catheter is positioned within a blood vessel within the brain adjacent the thrombus.

16. A method of capturing and retrieving a thrombus within vasculature of a living organism comprising:

inserting into the vasculature a medical device comprising;

a macrocoil in a thrombectomy catheter lumen, the macrocoil having a first set of loops therein in a thrombus engaging component having a length with a proximal end and a distal end, the length of the macrocoil consisting essentially of microcoils having a second set of loops therein that allow the length of both the macrocoil and the microcoils to be extendable;

a first wire capable of providing force on the distal end of the macrocoil;

a second wire capable of providing force on the proximal end of the macrocoil;

the loops of the macrocoil retracting to a maximum thickness of less than that of a thrombectomy catheter lumen when within the thrombectomy catheter lumen, and the loops of the microcoil expanding to a width of at least twice that of the thrombectomy catheter lumen when distended by relative movement between the first wire and second wire and wherein the macrocoil and the microcoil comprise non-thrombogenic compositions;

positioning at least a portion of the macrocoil past a thrombus;

adjusting the position of section of the macrocoil with respect to the thrombus by movement of at least one of the first wire and second wire to alter dimensions on the loops of both the first set of loops in the macrocoil and the dimensions of the second set of loops in the microcoils so that the loops of the microcoil are at least twice the thickness of the thrombectomy catheter lumen;

entraining the thrombus within coils of the macrocoil by movement of at least one of the first wire and second wire exerting force on the macrocoil and the microcoils; and

removing the thrombus by withdrawing the medical device from the vasculature.

19. The method of claim 16 wherein the first wire is attached to a first end of the macrocoil and the second wire being attached to a second end of the macrocoil, and opposed separating movement between the first wire and the second wire extends loops in the macrocoil and extends loops in the microcoils.

20. The method of claim 19 wherein the macrocoil has a dimension of less than 1 mm when within catheter lumen and the macrocoil expands when removed from the catheter lumen by force from the first or second wire.