Role of Rate Control and Regularization Through Pacing in Patients With Chronic Atrial Fibrillation and Preserved Ventricular Function: The VRR Study

Aim: High heart rates in chronic atrial fibrillation (CAF) is one of the factors responsible for hemodynamic alterations and may lead to tachycardiomyopathies. The ventricular rate regulation (VRR) study evaluates the effect of ventricular rate regularization in CAF patients with preserved ventricular function, marked ventricular rate variability, and indications for pacemaker (PM) implantation owing to symptomatic pauses. Rate regularization was achieved using VRR algorithm (INSIGNIA® pacemakers, Guidant Corp., St. Paul, MN, USA). Methods: One month after PM implantation, 58 patients followed two 3-month crossover periods (VRR-OFF; VRR-ON) in which the VRR algorithm was randomized and comp…