Fractal complexity alternations in paroxysmal atrial fibrillation patients with and without recurrence after pulmonary vein isolation

BackgroundPulmonary vein isolation (PVI) is a cornerstone therapy for paroxysmal atrial fibrillation (PAF). The variations in nonlinear heart rate variability (HRV) between patients with and without recurrences remain unclear. We aimed to characterize the nonlinear HRV before and after PVI in patients with and without recurrence. MethodsTwenty-five drug-refractory PAF patients (56.0 & PLUSMN; 9.1 years old, 20 males) who received PVI were enrolled. Holter electrocardiography were performed before, 1-3, and 6-12 months after PVI. After 8.2 & PLUSMN; 2.5 months of follow-ups after PVI, patients were divided into two groups: the recurrence (n = 8) and non-recurrence (n = 17) groups. Linear and nonlinear HRV variables were analyzed, including the Poincare Plot analysis and the Detrended Fluctuation Analysis (DFA). ResultsThe non-recurrence group, but not the recurrence group, had decreased high-frequency component (HF), the root mean square of successive RR interval differences (RMSSD), and the Poincare Plot index SD1 1-3 months after PVI and increased DFA(slope2) 6-12 months after PVI. The non-recurrence group's LF/HF ratio and DFA(slope1) decreased significantly 1-3 and 6-12 months after PVI, respectively, whereas there was no significant change in the recurrence group after PVI. ConclusionsSignificantly reduced vagal tone 1-3 months after PVI, increased long-term fractal complexity 6-12 months after PVI, and decreased sympathetic tone as well as short-term fractal complexity 1-3 and 6-12 months after PVI led to a better AF-free survival after PVI. These findings suggest that neuromodulation and heart rate dynamics play crucial roles in AF recurrence following PVI.

Automated summary

This study aimed to investigate the differences in nonlinear heart rate variability (HRV) between patients with and without recurrence before and after pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (PAF). The results showed that the non-recurrence group had significant decreases in the high-frequency component (HF), root mean square of successive RR interval differences (RMSSD), and Poincare Plot index SD1 1-3 months after PVI, and an increase in DFA(slope2) 6-12 months after PVI. The non-recurrence group also had significant decreases in the LF/HF ratio and DFA(slope1) 1-3 and 6-12 months after PVI, while no significant changes were observed in the recurrence group. These findings suggest that changes in vagal tone, long-term fractal complexity, and sympathetic tone as well as short-term fractal complexity play crucial roles in AF recurrence following PVI.