Apparatus for linear ablation

摘要

A cryogenic catheter (14) includes a flexible member (24) having an elongate, thermally transmissive region (26), and a cryogenic fluid path through the flexible member to the thermally transmissive region. The thermally transmissive region can be deformable from a linear configuration to an arcuate configuration, and can include multiple thermally transmissive elements ((34) for example) having a first side exposed to the cryogenic fluid path, and a second side exposed to points exterior to the flexible member. The thermally transmissive elements can be rigid or flexible longitudinal strips. Alternatively, annular, cylindrical, or wedge shaped metallic structures disposed in a spaced apart relationship, can define the thermally transmissive region. In other embodiments the thermally transmissive region is defined by a helical coil (52) that is at least partially embedded in the flexible member. The helical coil can also define at least a portion of the cryogenic fluid path through the flexible member, and include a gas expansion or boiling chamber (68).