Transvenous pacing accomplished from the right atrial appendage, either alone or in combination with right ventricular pacing, is becoming increasingly popular for selected patients in whom the contribution of atrial systole is advantageous. On the frontal chest radiograph, the pacemaker is seen to terminate over the right upper heart border, often seeming to turn abruptly cephalad. On the lateral radiograph, the lead follows a smooth, smooth, anterior curve in the midportion of the heart with its tip angled cephalad into the right atrial appendage. Complications associated with the use of this form of transvenous pacing are similar to those seen with other transvenous pacemakers; in addition, the catheter may be positioned inadvertently in the body of the right atrium, resulting in less effective atrial pacing.