Persistent atrial standstill following the Cox-maze III procedure: reversal with sustained atrial pacing.

Atrial standstill is a rare disorder of cardiac rhythm that is characterized by total absence of electrical activity in one or both atria. We report herein the case of a patient with atrial fibrillation and symptomatic 4.0 s pauses who received a ventricular demand pacemaker. The patient later underwent mitral valve replacement with a pericardial tissue valve and the Cox-maze III procedure for symptomatic mitral stenosis and atrial fibrillation. Following surgery, he developed atrial standstill and became pacemaker dependent. The pacemaker was later revised to an atrioventricular sequential pacemaker. Twelve hours after revision, atrioventricular sequential pacing was noted and mechanical function of the atria was confirmed by Doppler echocardiography.