Cystic tumour of the atrioventricular node: can an electrophysiological study predict sudden death?

A 58-year-old woman presented with palpitation. A resting electrocardiogram revealed sinus rhythm and first-degree atrioventricular (AV) block. Transthoracic echocardiography showed a 15 mm × 17 mm round tumour in the lower interatrial septum ( Panel A ) that appeared as high signal intensity on T1-weighted magnetic resonance …