The underlying principle of Cryoablation is the Joule-Thomson-Effect, where a refrigerant usually under high pressure in liquid form is allowed to expand suddenly through a porous plug into vacuum. This effect is used in the CoolLoop® catheter to create circular lines of lesions in the human atrium, in order to achieve debulking of the atria for prevention of AF.

Cryoablation comprises all methods of destroying tissue by freezing. Reactions induced may range from inflammation to destruction of tissue depending on the severity of the freezing injury. Tissue destruction in turn is based on two mechanisms: direct cell injury and vascular stasis.

As the CoolLoop catheter rapidly absorbs heat from the tissue, ice crystals form within the cells. This leads to immediate cell …