A COMPARISON OF VVIR AND DDDR PACING FOLLOWING CARDIAC TRANSPLANTATION

We compared the clinical course of patients paced in VVIR versus DDDR mode to determine the most appropriate method of pacing following card iac transplantation. Pacemaker implantation was required in 9 of 90 or thotopic cardiac transplants (10%). Indications included sinus bradyca rdia or sinus arrest (8 patients) and AV node dysfunction (1 patient). VVIR pacemakers were implanted in four patients and DDDR in five pati ents. DDDR patients: The mean P wave was 1.7 mV and the mean atrial st imulation threshold was 0.8 V (at 0.5 msec). During follow-up of to mo nths, two atrial lead complications developed (29% of leads in 33% of patients). No lead complications were directly related to endomyocardi al biopsy. VVIR patients: All four patients developed VA conduction wi th mean VA time 180 msec (160-240 msec). Two patients developed pacema ker syndrome. Conclusions: VA conduction and pacemaker syndrome may de velop in cardiac transplant recipients paced in the VVIR mode. Dual ch amber pacing is technically feasible and preferable following cardiac transplantation.