Successful surgical ablation of atrial fibrillation does not disturb long-term sinus rhythm variability.

Abstract

Surgical ablation of atrial fibrillation (AF) aims to restore normal sinus rhythm while protecting the sinus node from surgical damage. Surgical lesions may affect autonomic neural structures and influence physiological heart rate variability (HRV). The primary aim of this study was to describe long-term dynamics of HRV after successful surgical ablation of AF. The secondary aim was to compare sinus node function after successful ablation of AF with either left atrial modified Maze procedure or epicardial pulmonary vein isolation after long-term follow-up. This retrospective study included 75 patients who underwent successful ablation of paroxysmal or persistent AF (53 patients, 71%) and long-standing persistent AF (22 patients, 29%). Standard variables were selected to describe HRV and the minimal and mean heart rates. In all patients, a 24-h Holter ECG study was performed preoperatively, at hospital discharge and after 3, 6, 12 and 24 months. A significant reduction in the main HRV parameters and an increase in heart rate were observed at discharge when compared with the preoperative period. During follow-up, all HRV parameters returned to preoperative levels. No significant differences were observed in HRV parameters and HR between the modified Maze and pulmonary vein isolation procedure groups at any time. Successful surgical ablation of paroxysmal, persistent and long-standing persistent AF using either pulmonary vein isolation or modified left atrial Maze procedure does not disrupt long-term HRV. A significant early postoperative reduction in HRV with a gradual increase in the following months is typical in patients after surgical restoration of sinus rhythm.