Cryoablation apparatus with enhanced heat exchange area and related method

摘要

A cryoablation apparatus includes a distal energy delivery section to facilitate energy transfer to the tissue, resulting in faster achievement of tissue target temperatures. The energy delivery section includes a first heat exchange region and a second heat exchange region having a different heat exchange efficiency than the first heat exchange region. The first heat exchange region may comprise an increased surface area along a radial portion or length of the cryoprobe in contact with surrounding tissue. The heat exchange region may include ridges, texture, threads, and microtubes which serve to increase the thermal-contacting surface area and provide enhanced cryoenergy to the tissue.

主权项

1. A cryoablation method for applying cryoenergy to tissue comprising the steps of:
driving a liquid refrigerant along a first flowpath through a first cryoprobe having an energy delivery distal section, wherein said liquid refrigerant remains in a liquid-only state along the first flowpath; positioning said energy delivery distal section of said first cryoprobe in a vicinity of said tissue; transferring cryoenergy to said tissue to freeze said tissue through a first heat exchange area extending along said energy delivery distal section of said first cryoprobe; and wherein said first heat exchange area includes only one tubular-shaped outermost wall defining a passageway for accommodating the liquid refrigerant being transported through the energy delivery distal section, and said one tubular-shaped outermost wall further comprises an exterior surface formed of a discrete surface area enhancing structure extending radially and outwardly therefrom defining peaks and valleys along the exterior surface of the one tubular-shaped outermost wall, thereby increasing the surface area of the first heat exchange area along the energy delivery distal section of the first cryoprobe and wherein the first flowpath commences at a refrigerant source, continues through the first cryoprobe, through the energy delivery distal section, and returns to one of the refrigerant source or a reservoir, and wherein the refrigerant remains in the liquid only state during an entire first flowpath and during the step of transferring cryoenergy to the tissue.