title: Italian multicenter study on a single lead VDD pacing system using a narrow atrial dipole spacing.
abstract: Since November 1988, 514 patients with advanced atrioventricular (AV) block and normal sinoatrial function have received the single lead VDD pacing system Twinal 30 Lem/CCS in 30 Italian centers. At implantation, particular attention was paid to the correct positioning of the atrial dipole in the mid- to mid-high right atrium and to the atrial electrogram characteristics. The follow-up included a chest X ray, to be performed before discharge of the patient from the hospital, telemetric evaluations of the endoatrial potential, provocative tests for interferences by myopotentials, 24-hour ambulatory EGG recordings, and where possible, exercise stress tests. The mean follow-up duration was 15.2 months, ranging from 1 to 42 months. A very low percentage of chronic atrial fibrillation, loss of atrial sensing, and system replacement was reported, most of the patients (93.5%) being paced in VDD mode. All investigations indicated an excellent overall system performance, stable AV synchrony, and infrequent myopotential interference, and a low complication rate throughout the follow-up period.
mesh_terms: D000368:Aged; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D015716:Electrocardiography, Ambulatory; D004567:Electrodes, Implanted; D004867:Equipment Design; D005069:Evaluation Studies as Topic; D005080:Exercise Test; D005260:Female; D005500:Follow-Up Studies; D006327:Heart Block / Q000453:epidemiology / Q000628:therapy*; D006801:Humans; D007558:Italy; D008297:Male; D010138:Pacemaker, Artificial; D013997:Time Factors