Thrombus removal system and process

• US 20080091223A1
• Filed: 10/12/2007
• Published: 04/17/2008
• Est. Priority Date: 04/01/2005
• Status: Active Grant

• Current Assignee: Nexgen Medical Systems, Inc.
• Original Assignee: Nexgen Medical Systems, Inc.
• Inventors: Kucharczyk, John, Finitsis, Stephanos, Pokorney, James
• Granted Patent: US 8,603,122 B2
• Time in Patent Office: Days
• 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 2017/22034 for gripping the obstruction or the tissue part from inside

Abstract

A device capable of capturing and facilitating the removal of a thrombus in blood vessels (or stones in biliary or urinary ducts, or foreign bodies) uses a soft coil mesh with the aid of a pull wire or string to engage the surface of a thrombus, and remove the captured thrombus. The soft coil mesh 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 elements forming the macrocoil and allows for control of gripping forces on the thrombus while reducing non-rigid contact of the device with arterial walls. The use of multiple coil mesh elements, delivered through a single lumen or multiple lumens, preferably with separate control of at least one end of each coil, provides a firm grasp on a distal side of a thrombus, assisting in non-disruptive or minimally disrupted removal of the thrombus upon withdrawal of the device.

Claims

1. A medical device for removing a thrombus from a blood vessel, comprising

at least one microcatheter lumen, the at least one microcatheter lumen having at least one deployable macrocoil having a length comprising a) a continuous region of microcoils or b) at least two separate macrocoils segments comprising microcoils therein, each region or segment of the at least one macrocoil being capable of conformation to at least one solid object after deployment from the microcatheter lumen, and each of the at least one deployable macrocoils, when deployed to a location outside of the microcatheter lumen, is capable of being withdrawn from the location by withdrawal of the lumen.

2. The device of claim 1 wherein at least one of the at least two macrocoil segments comprises a macrocoil thrombus engaging component having a length with a proximal end and a distal end, the length of the macrocoil thrombus engaging component comprised of microcoils that allow the length of the macrocoil segment to be extendable and flexible.

3. The device of claim 2 wherein the at least two macrocoil segments each comprises a macrocoil thrombus engaging component having a length with a proximal end and a distal end, the length of each of the at least two macrocoil segments comprised of microcoils that allow the length of each macrocoil segment to be independently extendable, conformable and flexible

4. A medical device for removing a thrombus from a blood vessel, comprising

at least one microcatheter lumen having a length between a distal end and a proximal end, the at least one microcatheter lumen having within the at least one microcatheter lumen at least one region of a positionable and deployable macrocoil, the deployable macrocoil being deployable from the distal end of the microcatheter lumen and positionable about a shaped structure within a blood vessel distally located with respect to the length of the lumen.

5. The device of claim 4 wherein the macrocoil is conformable about the shaped structure because of flexibility and conformability in the macrocoil provided by microcoils within the macrocoil.

6. The device of claim 5 wherein the shaped structure comprises a thrombus within the blood vessel.

7. A method of capturing a solid object within a vessel in a patient comprising inserting a medical device for removing a solid object from a vessel, the device comprising the device of claim 5,

the method comprising inserting the medical device into a blood vessel so that a the microcatheter lumen is not beyond the solid object,

deploying a first at least one deployable macrocoil beyond the solid object to provide a distal engaging element beyond the solid object and deploying a capture element for the shaped structure that is not beyond the solid object to form a proximal engaging structure for the solid object comprising the distal macrocoil and the capture element on relatively opposite sides of the solid object.

8. The method of claim 7 wherein after forming the distal engaging structure and the proximal engaging structure, and directing the at least one deployable microcoil to conform to the solid object, withdrawing the medical device to withdraw the solid object from the vessel or move the solid object within the vessel.

11. A device for retrieval of objects from within vessels of patients comprising:

a length of microcoil having approximately helical turns continuously or within adjacent sections of the length of microcoil and the helical turns have an average diameter,

at least some of the continuous length or the segments in the length of microcoil having eyelets that extend beyond the average diameter, and a core wire passing through at least some adjacent eyelets from a distal end to a proximal end of the length of microcoil,

the core wire being restrained near the distal end of the length of microcoil.

9. A method of capturing a solid object within a vessel in a patient comprising

inserting the medical device of claim 11, the method comprising inserting the microcatheter lumen into a patient so that a first at least one deployable microcoil region or segment is beyond the solid object and a second at least one other microcoil region or segment is not beyond the solid object,

using the first at least one deployable macrocoil beyond the solid object to provide a distal engaging element of a microcoil segment beyond the solid object and deploying the second at least one other microcoil segment not beyond the solid object to form a proximal engaging structure for the solid object.

10. The method of claim 9 wherein after forming the distal engaging structure and the proximal engaging structure, withdrawing the medical device to withdraw the solid object from the vessel or move the solid object within the vessel.

12. The device of claim 11 wherein the average diameter of the helical turns is less than 0.050 inches.

13. The device of claim 12 carried within a lumen of a microcatheter wherein the lumen internal diameter is greater than the average diameter of the helical turns of the length of microcoil.

14. The device of claim 12 wherein tension applied on the proximal end of the core wire will cause the length of microcoil to form loops outside of the average diameter of the length of microcoil.

15. A device for insertion into a vessel from the removal of at least one solid object from within the vessel, the device comprising:

a catheter having a lumen;

within the lumen of the catheter is at least;

a macrocoil elongate element having an axis and a length,

multiple eyelets on the macrocoil elongate element that extend away from the axis, and

a core wire extending through at least two of the multiple eyelets;

wherein the core wire is attached at a distal point along the length of the macrocoil, wherein increasing tension on the core wire, which tension is in part guided by the core wire passing through multiple eyelets, causes the macrocoil to form loops, curves, bundles or a non-linear compressed shape.

16. The device of claim 15 wherein the macrocoil element consists of a continuous length of microcoils or segments of microcoils aling the length of the macrocoil that add flexibility and conformability to the macrocoil.

17. The device of claim 16 wherein the macrocoil element comprises a continuous length of microcoils.

18. The device of claim 17 wherein eyelets are formed along the length of the macrocoil element by dislocated microcoils extending away from the axis of the macrocoil elongate element and providing openings through which the core wire may pass.

19. The device of claim 15 wherein when tension is applied to the core wire, the macrocoil forms loops along the length of the macrocoil.

20. The device of claim 19 wherein at least some loops will be formed adjacent at least one eyelet.

21. A method of removing a solid object from a vessel using the device of claim 15 comprising:

inserting the catheter into a vessel adjacent a solid object in the vessel;

extending at least a distal end of at least one macrocoil element beyond the solid object, away from the catheter;

applying tension to the core wire;

retracting the at least distal end of the macrocoil element to reshape the at least one macrocoil and conform at least a portion of the macrocoil to a surface of the solid object; and

withdrawing the macrocoil element and moving the solid object.