Amplitude reduction of autonomic nerve function is correlated with ablation lesion quality in patients with paroxysmal atrial fibrillation.

ABSTRACT

OBJECTIVE: Circumferential pulmonary vein isolation (CPVI) is a common procedure that is performed on patients with atrial fibrillation (AF). However, AF may recur in some patients after treatment. This study assesses the association between autonomic modulation and late recurrence after CPVI and between autonomic modulation and ablation lesion quality. METHODS: We prospectively enrolled 72 patients with paroxysmal AF who underwent CPVI from January 2017 to January 2018. Pre- and post-ablation 24 h electrocardiograms were performed to document heart rate variability (HRV), which represents cardiac autonomic function. The intraablation force-time integral (FTI) was used to indicate the extent of ablation injury. Patients were followed up for 12 months after the procedure and cases of AF recurrence were recorded. RESULTS: Changes in HRV decreased after the procedure, which was correlated with FTI (ΔSDNN r = -0.26, P = 0.03; ΔrMMSD r = -0.28, P = 0.02; ΔlnHF r = -0.22, P = 0.04; ΔLnLF r = -0.29, P = 0.01). Patients without AF recurrence had more pronounced ΔLF (-21.84 ± 33.21% vs. -8.68 ± 34.59%, P = 0.01) and ΔHF (-17.26 ± 16.61% vs. -1.28 ± 9.81%, P = 0.01) than patients with recurrence. Multivariate regression analysis showed that both ΔLF (HR 1.07, P = 0.04) and ΔHF (HR 1.11, P = 0.01) were associated with AF recurrence. After adjusting for FTI, ΔLF was no longer associated with AF recurrence (HR 1.05, P = 0.10). ΔHF remained associated with AF recurrence (HR 1.08, P = 0.03), but the correlation coefficient was decreased (HR 1.08, P = 0.03). CONCLUSION: Decreased autonomic nerve function is a valid predictor of AF recurrence and is indicated by the extent of ablation injury, which is independently associated with AF recurrence after CPVI.