A 37-year-old man was referred for evaluation of a heart murmur detected recently during a routine checkup. The patient had an unsuspicious medical history, without previous infection, trauma, or connective tissue disease. He was completely asymptomatic while resting or exercising. Physical examination revealed a continuous 2/6 systolic-diastolic precordial murmur but was otherwise unremarkable. Transthoracic echocardiography demonstrated a left-to-right shunt that originated from the aortic bulbus, with a slightly enlarged right atrium and ventricle. Transesophageal echocardiography confirmed a noncoronary sinus of Valsalva aneurysm with rupture into the right atrium (Figure, A). Doppler imaging studies showed a prominent jet into the right atrium (flow velocity >4.5 m/s) and a smaller jet into the right ventricle (Figure, B; online-only …