Method of using a clot capture coil

• US 6,436,112 B2
• Filed: 06/25/2001
• Issued: 08/20/2002
• Est. Priority Date: 02/02/1996
• Status: Expired due to Term

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Wensel, Jeffrey P., Gobin, Y. Pierre
• Primary Examiner(s): Thaler, Michael H.
• Application Number:
  US09/891,100
• Publication Number:
  US 20020016609A1
• Time in Patent Office: 421 Days
• Field of Search: 606/151, 606/198, 606/191, 606/200, 606/159, 606/127, 606/128
• US Class Current: 606/159
• CPC Class Codes: A61B 17/22 Implements for squeezing-off ulcers or the like on the inside of inner organs of the body; Implements for scraping-out cavities of body organs, e.g. bones; Calculus removers; Calculus smashing apparatus; Apparatus for removing obstructions in blood vessels, not otherwise provided for dilators A61M29/00
• 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 2017/00867 shape memory effect
• CPC Class Codes: A61B 2017/22034 for gripping the obstruction or the tissue part from inside
• CPC Class Codes: A61B 2017/2212 having a closed distal end, e.g. a loop
• CPC Class Codes: A61B 2017/2215 having an open distal end
• CPC Class Codes: A61B 2017/2217 single wire changing shape to a gripping configuration
• CPC Class Codes: A61F 2002/016 made from wire-like elements
• CPC Class Codes: A61F 2002/30092 using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2210/0033 electrically, e.g. heated by resistor
• CPC Class Codes: A61F 2230/0006 circular
• CPC Class Codes: A61F 2230/0091 helically-coiled or spirally-coiled, i.e. having a 2-D spiral cross-section

Abstract

A clot and foreign body removal device is described which comprises a catheter with at least one lumen. Located within the catheter is a clot capture coil that is connected to an insertion mandrel. In one embodiment, the clot capture coil is made out of a solid elastic or superelastic material which has shape memory, preferably nitinol. The elasticity or superelasticity of the coil allows it to be deformed within the catheter and to then reform its original coil configuration when the coil is moved outside of the catheter lumen. In another embodiment the coil is a biphasic coil which changes shape upon heating or passing an electric current. Once the coil configuration has been established, the coil can be used to ensnare and corkscrew a clot in a vessel. A clot is extracted from the vessel by moving the clot capture coil and catheter proximally until the clot can be removed or released into a different vessel that does not perfuse a critical organ. Foreign bodies are similarly captured by deploying the coil distal to the foreign body and moving the clot capture coil proximally until the foreign body is trapped within the coil. By removing the device from the body, the foreign material is also removed.

Claims

1. A method of removing an obstruction in a blood vessel comprising:

advancing a catheter through an obstruction, the catheter having a lumen;

positioning an obstruction retriever within the lumen of the catheter, the obstruction retriever having an obstruction engaging portion extending from an insertion element, the obstruction engaging portion being an elongate element which extends from the insertion element to a free end, the elongate element forming a coiled section, the coiled section having coils which increase in size as they extend distally from a proximal end of the coils section, the obstruction engaging portion being movable between a collapsed position and an expanded position and being in the collapsed position when positioned in the lumen and being naturally biased toward the expanded position when positioned outside the lumen;

moving the obstruction engaging portion into engagement with the obstruction; and

removing the obstruction.

2. The method of claim 1, wherein the positioning step is carried out with the elongate element forming coils of decreasing diameter extending distally from the coils of increasing size.

3. The method of claim 1 wherein the obstruction engaging portion is made of a superelastic material.

4. The method of claim 1 further comprising introducing the catheter through a second catheter to the obstruction.

5. The method of claim 1, further comprising:

loading the obstruction retriever into the catheter in a retrograde direction; and

thereafter introducing the catheter through the second catheter.

6. The method of claim 1 wherein the obstruction engaging element has a helical shape.

7. The method of claim 1 wherein the obstruction engaging element has a generally conical shape.

8. The method of claim 1 wherein the catheter has only one lumen.

9. The method of claim 1 wherein the obstruction engaging element. extends proximally from the insertion element to the free end when in the expanded position.

10. The method of claim 1 wherein the obstruction engaging portion extends distally from the insertion element to the free end when in the expanded position.

11. The method of claim 1 wherein the obstruction retriever has substantially only one filament which extends to the free end.

12. The method of claim 1 wherein:

the moving step is carried out by moving the obstruction engaging portion proximally into engagement with the obstruction.

13. The method of claim 1 wherein the moving step is carried out by rotating the obstruction engaging portion.