Atrial pacing from the coronary vein. Ten-year experience in 50 patients with implanted pervenous pacemakers.

During the past ten years, pervenous atrial pacemakers have been implanted in 50 patients (mean age 68 years, 60% males) using an electrode positioned in the coronary vein. The indications for atrial pacing were symptomatic sinus bradycardia (72%), atrial brady-tachy syndrome (20%), and recurrent tachyarrhythmias (8%). Atrial pacemakers have been implanted for a total of 1531 pacing months, average 31 months per patient, median 26 months and range 3-97 months. Effective atrial pacing has been achieved with Medtronic model 5818 and 6904 electrodes. Unipolar or bipolar atrial pacing has been equally effective, and commercially available Medtronic 5950, Cordis 162 and CPI 602 pulse generators have been utilized without difficulty. A total of 11 electrode related malpacing events occurred in the ten-year period with a malpacing event rate of 10% in the first pacing month, 1.1% per paced month during the next six months, and 0.25% per paced month thereafter. Life table analysis reveals that effective atrial pacing was achieved in 76% of the patients during a follow-up of more than five years. This experience substantiates the long-term safety and effectiveness of atrial pacing from the coronary vein using standard pacemaker electrodes and generators.