Method for RF ablation using cooled electrode

United States Patent im

Imran et al.

[54] METHOD FOR RF ABLATION USING COOLED ELECTRODE

[75] Inventors: Mir A. Imran, Palo Alto; Mark L.

Pomeranz, Los Gatos, both of Calif.

[73] Assignee: Cardiac Pathways Corporation, Sunnyvale, Calif.

[21] Appl. No.: 214,785

[22] Filed: Mar. 16,1994

Related U.S. Application Data

[62] Division of Ser. No. 983,732, Dec. 1, 1992, Pat. No. 5,348,554.

[51] Int. CI.6 A61B 17/39; A61N 1/05

[52] U.S. CI 606/41; 607/99;

607/105; 607/113; 607/122

[58] Field of Search 607/98, 99, 101, 102,

607/104, 105, 113, 116, 122; 606/41, 45, 49

[56] References Cited

U.S. PATENT DOCUMENTS

5,230,349 7/1993 Langberg 607/122

5,281,213 1/1994 Milder 606/15

5,334,193 8/1994 Nardella 606/41

■ill

US005423811A

[ii] Patent Number: 5,423,811

[45] Date of Patent: Jun. 13,1995

FOREIGN PATENT DOCUMENTS

1690786 11/1991 U.S.S.R 606/41

OTHER PUBLICATIONS

Wittkempf et al., "Radiofrequency Ablation ... Catheter" JACC, vol. 11, No. 2., Feb. 1988: 17 A Abstracts.

Primary Examiner—Lee S. Cohen

Attorney, Agent, or Firm—Flehr, Hohbach, Test,

Albritton & Herbert

[57] ABSTRACT

A catheter for radio frequency ablation with a cooled electrode for use in tissue having a surface comprising an elongate member having proximal and distal extremities. A metal conducting electrode secured to the distal extremity of the elongate member and having a chamber therein. A conductor extends through the elongate member from the proximal to the distal extremity for supplying radio frequency energy to the electrode. The elongate member has a lumen in the distal extremity which is in communication with the chamber. A coolant is disposed in the chamber and in contact with the electrode for dissipating heat created in the electrode by the application of radio frequency energy thereto.

6 Claims, 6 Drawing Sheets