Coupled pacing controls rapid heart rates better than paired pacing during atrial fibrillation

Delivery of a ventricular extrastimulus shortly after the effective refractory period (ERP) of a sensed (coupled pacing; CP) or a paced (paired pacing; PP) ventricular event can instantly decrease the mechanical pulse rate (MPR) during rapidly conducting atrial fibrillation (AF). We compared the short-term rate-controlling effects of CP and PP during AF with rapid ventricular rates. Sixteen patients with ongoing, spontaneous AF were examined. Mechanical pulse rate was registered via arterial pressure tracings. During CP a coupling interval (CI) of ERP20 ms was used to reach an optimal haemodynamic effect. Paired pacing was started at a basic cycle length (CL) of 500 ms followed by an extrastimulus with an CI of ERP20 ms. Drive train was changed at 50 ms increments until the lowest MPR was reached. Proarrhythmic effects were characterized by the number of premature ventricul Both CP and PP can reduce the MPR during rapidly conducting AF. Coupled pacing is more applicable, but PP has the advantage to achieve different target heart rates. Paired pacing has more proarrhythmic effects as compared with CP.