[Pacemaker syndrome and retrograde ventriculoatrial conduction]

19 cases of pacemaker syndrome were observed in 121 patients implanted with VVI pacemakers. The main manifestations of pacemaker syndrome were dizziness, lightheadedness, fatigue, hypotension and congestive cardiac failure after permanent ventricular pacing. The incidence of pacemaker syndrome was 20% in patients with sick sinus syndrome and 13.2% with A-V block. Pacemaker ECG showed retrograde ventriculoatrial conduction in 25 of 121 cases. Among these patients, 14 (56%) had pacemaker syndrome, while only 5 of 96 cases without ventriculoatrial conduction had this syndrome, so the incidence of the two groups were quite different, P less than 0.0001. The frequency of ventriculoatrial conduction in patients with sick sinus syndrome was higher than in patients with A-V block (16/45 vs 9/76, P less than 0.05). The electrophysiologic study were performed in 17 cases before PM implantation. 3 cases had 170-190 ms ventriculoatrial 1:1 conduction. Retrograde ventriculoatrial conduction in pacemaker ECG were present during ventricular pacing in all of them.