Background: Symptomatic prolonged sinus pauses upon termination of atrial fibrillation (AF) are an indication for pacemaker implantation.
Methods and results: We evaluated the clinical outcomes of 4 patients who showed prolonged sinus pauses (> 2 seconds) upon termination of AF and thus underwent ablation. The ablative procedure included pulmonary vein isolation, superior vena cava isolation, and cavo-tricuspid isthmus ablation. Twenty-four-hour ambulatory electro-cardiogram monitoring was performed before and 1 month after ablation. The maximum sinus pause decreased from 4.5 +/- 2.1 seconds before ablation to 1.7 +/- 0.2 seconds after ablation. Sinus pauses > 2.0 seconds disappeared after ablation in all 4 patients. Minimum heart rate increased from 35.0 +/- 8.1 beats/minute before ablation to 52 +/- 6.7 beats/minute after ablation. The number of heart beats in 24 hours did not change significantly after ablation.
Conclusion: Prolonged sinus pauses after paroxysmal AF may result from depressed sinus node function, which can be eliminated by curative ablation of AF.