摘要 |
A thermal ablation catheter for microtransection or macrotransection of conduction paths within the heart includes a resistive heating element (14) at its distal end for highly localized treatment. The heating element includes a resistive wire loop (28) connected to an external power source and has a prescribed shape to insure that the wire loop is approximately perpendicular to the surface to be treated. A reference electrode (16) spaced 8-10 inches from the distal end is used in conjunction with the wire loop (28) (the sensing electrode) to sense potentials in the heart. The catheter is advanced through a blood vessel to the region of the A-V node and the His bundle, and the sensing mode is used to determine the desired location for treatment. The wire loop is then energized with d.c. current for a predetermined time on the order of 2-5 seconds to cause localized thermal ablation of the target area. |