5,147,355 9/1992 Friedman et al. .
5,224,943 7/1993 Goddard .
5,228,442 7/1993 Imran .
5,231,995 8/1993 Desai .
5,281,213 1/1994 Milder et al. .
5,281,215 1/1994 Milder et al. .
5,293,869 3/1994 Edwards et al. .
5,325,286 6/1994 Fowle 606/23
5,334,181 8/1994 Rubinsky et al. .
5,403,309 4/1995 Coleman et al. .
5,423,807 6/1995 Milder .
5,452,582 9/1995 Longsworth 62/51.2
5,487,385 1/1996 Avitall .
5,520,682 5/1996 Baust et al. .
5,545,200 8/1996 West et al. .
5,624,392 4/1997 Saab 604/43
Primary Examiner—Michael Peffley
Assistant Examiner—Roy Gibson
Attorney, Agent, or Firm—Nutter, McClennen & Fish, LLP  ABSTRACT
A cryogenic catheter includes a flexible member having an elongate, thermally-transmissive region and a cryogenic fluid path through the flexible member to the thermallytransmissive region. The thermally-transmissive region can be deformable from a linear configuration to an arcuate configuration and can include multiple thermallytransmissive elements 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, cylidrical, 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 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.
8 Claims, 5 Drawing Sheets