This is a much newer treatment for supraventricular tachycardia (SVT) involving the atrioventicular (AV) node directly. SVT involving the AV node is often a contraindication for using radiofrequency ablation because of the risk of injuring the AV node, forcing patients to receive a permanent pacemaker. With cryoablation, areas of tissue can be mapped by limited, reversible, freezing (e.g., to -10 C). If the result is undesirable, the tissue can be rewarmed without permanent damage. Otherwise, the tissue can be permanently ablated by freezing it to a lower temperature (e.g., -73 C).