Improved electrophysiological mapping and ablation catheter and method.

摘要

A mapping and ablating catheter having a short distal tip electrode (40, 58, 68), comprising a bio-compatible outer surface and a thermal dissipating mass for dissipating heat received by the electrode. The outer surface may be formed by plating a thin layer of gold or platinum on the dissipating mass, or the entire electrode may be formed of a homogenous material such as a gold alloy that is bio-compatible thereby forming the outer surface with the mass itself. An alloy having a thermal conductivity greater than pure platinum is used so that the ablation procedure can be completed before exceeding the temperature limits. In one case, the entire electrode was formed of an 88% gold 12% nickel alloy. The electrical feed to the electrode is oversized to also dissipate heat received by the electrode. The electrode is no greater than five mm in length yet produces an ablation volume equal to or greater than longer electrodes. One or more band electrodes (70) may also include thermal dissipating masses.