| abstract |
An ablation catheter for performing tissue ablation has an elongate shaft with a lumen. A tip ablation electrode is mounted on the distal end of the shaft. The tip electrode has walls that, together with the plug, define a chamber. The tip electrode has a fluid exit port. The catheter has a cooling fluid delivery system with a connection to a fluid source and a fluid delivery tube within the lumen of the elongate shaft. The fluid delivery tube penetrating said plug and delivers fluid to the fluid exit port. The catheter has a valve assembly in located in the chamber between the fluid delivery tube and the fluid exit port. The valve assembly prevents the flow of cooling fluid through the fluid delivery tube when in the closed position. |