Patent ID: 8535301

Claim:
A method of ablating tissue, comprising: providing a tissue ablation probe comprising: a tubular shaft having a proximal end portion and a distal end portion, the distal end portion including a cryogenic ablation surface, and defining a communication passageway; a cryogen delivery tube extending through the communication passageway from the proximal end portion of the tubular shaft to the distal end portion of the tubular shaft and including at least one aperture proximate the cryogenic ablation surface, wherein the cryogen delivery tube and the tubular shaft define therebetween a boiler chamber adjacent the cryogenic ablation surface and an exhaust passageway extending through the communication passageway from the boiler chamber to the proximal end portion of the tubular shaft; shaping the tubular shaft and the cryogen delivery tube via plastic deformation such that the cryogenic ablation surface conforms to a surface of cardiac tissue to be treated; introducing the tissue ablation probe into a patient's body; manipulating the tissue ablation probe such that the cryogenic ablation surface contacts the surface of cardiac tissue to be treated; delivering a pressurized cryogen via the cryogen delivery tube such that it exits the at least one aperture and expands in the boiler chamber, thereby cooling the cryogenic ablation surface via the Joule-Thompson effect; and recovering the expanded cryogen via the exhaust passageway.