Transient complete atrioventricular block during catheter balloon cryoablation of atrial fibrillation: a case report

A 27-year-old man with normal heart and paroxysmal atrial fibrillation was referred for AF cryoablation. At first, the left pulmonary veins (PVs) were isolated with two 180  s cryoenergy applications in each vein. Then, the balloon was moved to the right inferior PV (RIPV) and two consecutive applications of cryoenergy, reaching a minimum temperature of −38 °C and −35 °C, were unable to isolate RIPV. The balloon was positioned in the right superior PV and i solation was obtained with two cryoenergy applications at −57ºC and −56ºC. The balloon was then repositioned in the RIPV and a third application was delivered, reaching a minimum temperature of −42ºC. During this application, patient presented complete atrioventricular (AV) block (Figure) and the cryoablation was interrupted. The block persisted despite 2  mg atropine. Conduction recovered progressively 23 min after cryoablation. Coronary angiography performed 30 min after AV block showed a patent AV node artery originating from the right coronary artery.
Source: Europace - Category: Cardiology Source Type: research