| abstract |
To cause controlled tissue necrosis, a catheter is inserted into the mediastinum, to the posterior side of the heart, adjacent the left ventricle. A gas or liquid medium is passed through the catheter and into a collapsible and expandable vessel connected to a distal end of the catheter, to expand the vessel to define an interior chamber. The vessel has a flexible outer surface region, which is guided to a that conforms to tissue of the heart. A second gas or liquid medium is admitted through the catheter to cause cooling of the flexible outer surface region, while maintaining contact with the heart for a predetermined time to, causing cryoablation which blocks undesired transmission of natural electrical signals by the tissue. |