Ablation catheter with selectively deployable electrodes

• US 5,078,717 A
• Filed: 09/10/1990
• Issued: 01/07/1992
• Est. Priority Date: 04/13/1989
• Status: Expired due to Fees

• Current Assignee: Gyrus Medical Incorporated (Olympus Corporation)
• Original Assignee: Everest Medical Corp. (Olympus Corporation)
• Inventors: Stasz, Peter, Parins, David J., Rydell, Mark A.
• Primary Examiner(s): Cohen, Lee S.
• Application Number:
  US07/580,782
• Time in Patent Office: 484 Days
• Field of Search: 606/33, 606/41, 606/45-48, 606/50, 128/786
• US Class Current: 606/48
• 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 2017/00292 mounted on or guided by flexible, e.g. catheter-like, means
• CPC Class Codes: A61B 2018/00196 reciprocating lengthwise
• CPC Class Codes: A61B 2018/00232 having an irregular shape
• CPC Class Codes: A61B 2018/1435 Spiral
• CPC Class Codes: A61B 2018/1861 with an instrument inserted into a body lumen or cavity, e.g. a catheter
• CPC Class Codes: A61M 2025/1086 having a special balloon surface topography, e.g. pores, protuberances, spikes or grooves
• CPC Class Codes: A61M 3/0279 Cannula; Nozzles; Tips; their connection means

Abstract

A RF ablation catheter for removing athero-stenotic lesions or modifying the tissue characteristics of the interior walls of selected blood vessels is described. The catheter has a distal tip member which is disposed in a working relation with the lesion to be removed during the initial placement of the catheter within the vascular system. Means are provided for increasing the cross-sectional profile of the tip member to thereby cause it to move into engagement with the lesion to be excised. The application of an RF voltage across a pair of bipolar electrodes is used to create an electric arc for effecting the cutting action, or alternatively, just sufficient RF energy to sear or otherwise alter the tissue surfaces engaged by the distal tip member.

Claims

1. An RF ablation catheter for electrosurgically removing tissue deposits from the interior of a blood vessel, comprising:

(a) an elongated, flexible, plastic tubular member having a distal end and a proximal end and an outside diameter which is less than the internal diameter of the blood vessel to be treated;

(b) an elongated, flexible member coaxially disposed within said plastic tubular member, said elongated flexible member having a distal end extending beyond said distal end of said plastic tubular member and a protuberance attached to said distal end of said flexible member;

(c) at least two flexible, electrically conductive electrode strips having first and second ends, said first end of said electrode strips being affixed to said distal end of said plastic tubular member and said second end of said electrode strips affixed to said protuberance, such that said strips are in parallel non-contacting relation with respect to one another and arranged to bow outwardly to exhibit an increased cross-sectional dimension when said elongated flexible member is tensioned by pulling in the proximal direction to decrease the spacing between said distal end of said plastic tubular member and said protuberance.