Fluid cooled ablation catheter and method for making

摘要

A catheter assembly (2) includes a catheter shaft (6) having a tip portion (10) with a hollow interior (30) and a linear ablation electrode (18, 34, 36, 44, 58) spaced apart from the distal end (22) of the tip portion. The electrode has an inner surface (28) which is effectively fluidly exposed to the hollow interior so that a cooling fluid (32) passing through the interior contacts the inner surface so to effectively cool the electrode. The electrode can include a series of band electrodes (18, 34) or one or more spiral electrodes (36, 44, 58). One method for making the tip portion involves mounting the electrode to a mandrel, filling the spaces between the edges (26) of the electrode with a polymer and then removing the resulting tubular structure from the mandrel. The cooling fluid can pass through a hollow spiral electrode (58) for enhanced cooling effectiveness.