Atrial Fibrillation During A‐V Sequential Pacing

Atrial fibrillation resulted from competition between the P wave and a unipolar cathodal stimulus from the atrial output of an A‐V sequential pacemaker Review of 31 patients with recently implanted A‐V sequential pacemakers revealed that five, who had not had atrial fibrillation or flutter before implant, developed atrial arrhythmia early after implant As occasional placement of an atrial stimuJus in tlie atrial vulnerable period can occur during normal function, pacer induced atrial fibrillation must be expected Atrial sensing to ensure lack of competition between pacer and spontaneous atrial activity is desirable