Apparatus and method for treating venous reflux

• US 6,712,815 B2
• Filed: 01/16/2002
• Issued: 03/30/2004
• Est. Priority Date: 01/16/2001
• Status: Expired due to Fees

• Current Assignee: Cytyc Surgical Products II Incorporated (Hologic Incorporated)
• Original Assignee: Novacept Inc. (Hologic Incorporated)
• Inventors: Hilario, Estela, Skalnyi, Eugene, Sampson, Russell M.
• Primary Examiner(s): Gibson, Roy D.
• Assistant Examiner(s): ROANE, AARON F
• Application Number:
  US10/052,157
• Publication Number:
  US 20020143325A1
• Time in Patent Office: 804 Days
• Field of Search: 606/41, 606/45, 606/47-50
• US Class Current: 606/41
• CPC Class Codes: A61B 18/1492 having a flexible, catheter-like structure, e.g. for heart ablation A61B18/1477 takes precedence
• CPC Class Codes: A61B 2017/22067 Blocking; Occlusion A61B2017/22054 takes precedence
• CPC Class Codes: A61B 2018/00214 Expandable means emitting energy, e.g. by elements carried thereon
• CPC Class Codes: A61B 2018/00261 arranged in a line
• CPC Class Codes: A61B 2018/00345 Vascular system
• CPC Class Codes: A61B 2018/00404 Blood vessels other than those in or around the heart
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/00619 Welding
• CPC Class Codes: A61B 2018/00755 Resistance or impedance
• CPC Class Codes: A61B 2018/00875 Resistance or impedance
• CPC Class Codes: A61B 2218/002 Irrigation
• CPC Class Codes: A61B 2218/007 Aspiration

Abstract

Disclosed is an ablation method and apparatus used to close veins for treatment of venous insufficiency disease. The apparatus includes a catheter proportioned for insertion into a vein, a pair of inflatable balloons spaced apart on the catheter body, and an ablation electrode array disposed between the balloons. According to the disclosed method, the catheter is introduced into the vein to be treated and the balloons are distended. Blood is flushed and aspirated from the site between the balloons. RF power is applied to the electrode array, causing scarring of the vessel walls and eventual sealing of the vein.

Claims

1. A method of sealing a blood vessel, comprising the steps of:

providing a catheter including an elongate body, a pair of inflatable balloon members on the elongate body, and an electrode array on the elongate body between the balloons;

positioning the catheter within a blood vessel;

inflating the balloon members into contact with an interior wall of the blood vessel;

flushing blood from the portion of the blood vessel extending between the inflated balloon members;

energizing the electrode array to cause ablation of the interior wall of the blood vessel;

removing the catheter from the blood vessel; and

compressing the blood vessel, causing opposed ablated regions of the interior wall to seal against one another.

2. The method of claim 1 wherein a vacuum is applied to the portion of the blood vessel extending between inflated balloon members during ablation, said vacuum collapsing the vessel, thereby drawing the interior wall into contact with the electrode array.

3. The method of claim 2 wherein the catheter elongate body includes a plurality of openings, and wherein the vacuum is applied through the openings.

4. The method of claim 1 wherein a vacuum is applied to the portion of the blood vessel extending between inflated balloon members during ablation, said vacuum drawing moisture generated during ablation away from the tissue.

5. The method of claim 4 wherein the catheter elongate body includes a plurality of openings, and wherein the vacuum is applied through the openings.

6. The method of claim 1, wherein the flushing step includes flushing the portion of the blood vessel extending between the balloon members with saline, and aspirating blood and saline from the said portion of the blood vessel.

7. The method of claim 1, wherein the catheter elongate body includes a plurality of openings, and wherein the aspirating step includes applying a vacuum to the catheter to aspirate the blood out of the vessel through the openings.

8. The method of claim 1 wherein the electrode array is a bipolar array.

9. The method of claim 1 wherein the method further includes the steps of, prior to energizing the electrode array to cause ablation:

positioning the electrode array in contact with the interior wall of the blood vessel and measuring impedance of the tissue in contact with the electrode array; and

automatically selecting between a low impedance transformation circuit and a high impedance transformation circuit based on the impedance of the tissue in contact with the electrode array.

10. The method of claim 9 wherein the step of measuring the impedance of the tissue in contact with the electrode array includes providing a low-power RF signal to the electrode array.

11. The method of claim 9 wherein the step of selecting includes selecting the transformation circuit having an impedance closest to the measured impedance of the tissue in contact with the electrode array.

12. The method of claim 1 wherein the energizing step causes flow of current into the tissue, and wherein the method further includes the step of causing automatic termination of current flow into the interior wall once a selected ablation depth has been approximately reached.

13. The method of claim 12 wherein said termination occurs regardless of whether the electrode array continues to be energized.

14. The method of claim 1 wherein the removing step includes the step of collapsing the catheter into a reduced diameter step and withdrawing the collapsed catheter from the vessel.

15. The method of claim 14 wherein the collapsing step includes the step of applying a vacuum to a lumen in the catheter.