Figure 1 A 67-year-old man was referred with unstable angina pectoris, and symptomatic bradycardia. The ECG revealed a Wenckebach-type atrioventricular block (Fig. 1b). A DDD-pacemaker system was implanted. Coronary angiography demonstrated severe triple vessel and left main disease, and the patient subsequently underwent coronary bypass grafting. A routine echocardiogram, performed 3 months after surgery, showed no sign of mechanical activity of the left atrium, confirmed by the missing A-wave in the mitral flow curve, while flow across the tricuspid valve was normal (Fig. 1a).