Patent ID: 8728074

Claim:
A catheter assembly comprising a catheter shaft having a catheter lumen accommodating passage of an irrigation tube, an energy delivery device carried by the catheter, the energy delivery device including a plurality of support arms, the support arms including a first lumen and a second lumen, wherein the first and second lumens have a stepped proximal configuration, a plurality of electrodes, each electrode carried by one of the plurality of support arms, the electrodes being advanceable from the first lumen outward from the support arm through a first opening in the support arm and retractable within the first lumen through the first opening, and an irrigation manifold coupled to the energy delivery device and fixed with respect to the catheter shaft and in fluid communication with the second lumens and the irrigation tube, wherein irrigation fluid is directed through the irrigation tube to the manifold and exiting from the manifold for flowing into the second lumens of the support arms and further flowing for delivery out through an irrigation opening in the support arms communicating with the second lumen, wherein the irrigation opening communicating with the second lumen discharges irrigation fluid in the vicinity where the electrode projects through the first opening communicating with the first lumen.