Cryoablation is a medical procedure that uses extreme cold to destroy abnormal tissue, such as tumours or abnormal heart tissue. During cryoablation, a thin, flexible probe or catheter is inserted through a small incision or natural opening in the body and guided to the site of the abnormal tissue. The tip of the probe is then cooled to very low temperatures using a gas, such as argon or nitrogen, which causes the tissue to freeze.