IMPROVED ELECTROPHYSIOLOGICAL MAPPING AND ABLATION CATHETER AND METHOD

摘要

A mapping and ablating catheter having a short distal tip electrode 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 itsel f. An alloy having a thermal conductivity greater than pure platinum is used so that the ablation procedure can be completed before exceeding the temperatur e limits. In one case, the entire electrode was formed of a 88% gold 12% nicke l 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 lengt h yet produces an ablation volume equal to or greater than longer electrodes. One or more band electrodes may also include thermal dissipating masses .