Pre-cardioversion heart rate variability predicts recurrence of atrial fibrillation after electrical cardioversion

Abnormalities of the cardiac autonomic nervous system could trigger the relapse of atrial fibrillation (AF) after electrical cardioversion. We analyzed pre-cardioversion heart rate variability (HRV), and sought to find its predictive value for the recurrence of AF after successful direct current cardioversion (DCC). Ventricular-to-ventricular (RR) intervals were used to calculate HRV variables. Among 144 patients with persistent AF, DCC successfully converted AF in 117 (81%) patients. HRV variables were not related with the acute cardioversion results. At 3-week follow-up, 60 (51%) patients showed AF recurrence. Mean RR, ASDRR, rMSSD, and VLF were independent predictors for early AF recurrence after successful cardioversion. During 1-year follow-up, 83 (74%) patients had AF recurrence. Mean RR, SDRR, rMSSD, pRR50, VLF, and LF/HF ratio were independent predictors of late AF recurrence. Using 3 HRV variables (mean RR, rMSSD, and VLF) that were independent predictors of both early and late AF recurrence, there was a graded risk of AF recurrence that was correlated with the number of dichotomized HRV predictors. Pre-cardioversion HRV parameters, especially mean RR, rMSSD, and VLF, could predict early and late recurrence of AF in patients after successful DCC, whereas the acute success of DCC could not be predicted by HRV. The cardiac autonomic nervous system might play an important role in the recurrence of AF after electrical cardioversion