Abstract: A cryogenic catheter includes an outer flexible member having at least one cryogenic fluid path through the flexible member. The at least one fluid path is defined by a plurality of flexible members disposed within the outer flexible member.

Abstract: A catheter for ablating tissue, for example to treat a cardiac arrhythmia, includes a handle, a shapeable shaft and a distal ablation segment. The shaft retains a first position until manipulated to a further position with the application of moderate manual pressure. The shaft incorporates plastically deformable elements and is shapeable to conform to an insertion path or the particular anatomy of a patient for accessing a site to be ablated. Once shaped, the shaft retains its shape as the catheter is inserted or manipulated to the predetermined tissue treatment location and the distal segment is urged into contact with the tissue site. A deflection mechanism may be provided to facilitate navigation to, or to deflect the ablation segment into conformal contact with, the tissue target. In a further or alternative embodiment, a second or auxiliary shaft member extends distally from the ablation segment, allowing the segment to be threaded by or pulled past occluding tissue to a remote target tissue site.

Abstract: A cryocatheter for treatment of tissue includes a coolant line communicating with a cryochamber having a coolant receiving interior and a thermally conductive wall for contacting and conductively treating tissue. A return line returns spent coolant, and an insert or partition in the cryochamber conditions flow or channels fluid from the coolant line to the return line to enhance the rate or uniformity of cooling. The partition may extend axially to define an elongated sub-chamber which is preferentially cooled, or it may isolate one side to define an uncooled side of the cryochamber. The partition may extend axially to define a sub-chamber extending along a segmented length around a partial circumference of the catheter tip, or may channel the coolant from a central region outwardly against the peripheral wall of the cryochamber. The return line may be a vacuum return line.

Abstract: A cryogenic catheter having an elongate outer member and a plurality of inner members disposed within the elongate outer member is provided. The inner members define at least one cryogenic path through the outer member. At least one of the inner members has at least one controllable opening formed thereon to selectively release cryogenic fluid. The inner members also include an overtube and an injection tube slideably disposed to one another.

Abstract: A medical device includes a flexible member having a variable geometry tip with a thermally-transmissive region. A smooth fluid path is provided through the flexible member to and from the variable geometry, thermally-transmissive region. The thermally-transmissive region can be deformed.