Denervation as a Common Mechanism Underlying Different Pulmonary Vein Isolation Strategies for Paroxysmal Atrial Fibrillation: Evidenced by Heart Rate Variability after Ablation

Abstract

Backgrounds. Segmental and circumferential pulmonary vein isolations (SPVI and CPVI) have been demonstrated to be effective therapies for paroxysmal atrial fibrillation (PAF). PVI is well established as the endpoint of different ablation techniques, whereas it may not completely account for the long-term success. Methods. 181 drug-refractory symptomatic PAF patients were referred for segmental or circumferential PVI (SPVI = 67; CPVI = 114). Heart rate variability (HRV) was assessed before and after the final ablation. Results. After following up for 62.23 ± 12.75 months, patients underwent 1.41 ± 0.68 procedures in average, and the success rates in SPVI and CPVI groups were comparable. 119 patients were free from AF recurrence (SPVI-S, n = 43; CPVI-S, n = 76). 56 patients had recurrent episodes (SPVI-R, n = 21; CPVI-R, n = 35). Either ablation technique decreased HRV significantly. Postablation SDNN and rMSSD were significantly lower in SPVI-S and CPVI-S subgroups than in SPVI-R and CPVI-R subgroups (SPVI-S versus SPVI-R: SDNN 91.8 ± 32.6 versus 111.5 ± 36.2 ms, rMSSD 47.4 ± 32.3 versus 55.2 ± 35.2 ms; CPVI-S versus CPVI-R: SDNN 83.0 ± 35.6 versus 101.0 ± 40.7 ms, rMSSD 41.1 ± 22.9 versus 59.2 ± 44.8 ms; all P < 0.05). Attenuation of SDNN and rMSSD remained for 12 months in SPVI-S and CPVI-S subgroups, whereas it recovered earlier in SPVI-R and CPVI-R subgroups. Multivariate logistic regression analysis identified SDNN as the only predictor of long-term success. Conclusions. Beyond PVI, denervation may be a common mechanism underlying different ablation strategies for PAF.

A square root pattern of changes in heart rate variability during the first year after circumferential pulmonary vein isolation for paroxysmal atrial fibrillation and their relation with long‑term arrhythmia recurrence

“…10 The absolute value of SDNN at 3 months after CPVI was previously identified as an independent risk factor for an AF relapse. 8 However, our study further underlines the utility of the periprocedural SDNN analysis. First, we show that the PAF patients with higher preablation SDNN (as a measure of overall HRV) are the best candidates for CPVI.…”

“…Predicting circumferential pulmonary vein isolation outcome with the periprocedural assessment of changes in heart rate variability Previous studies identified changes in HRV occurring immediately after CPVI as a predictor of AF recurrence. 3,[6][7][8]12,13,15 Thus, postablation findings of high HF and a low LF / HF ratio or that changed by more than 0.26 were all independently associated with LRAF. 6,7 However, interpreting changes in the HRV frequency parameters (ie, HF and LF) is limited because their assessment depends considerably on respiration and measurement conditions.…”

“…1 Several studies reported a significant change of the HRV parameters after CPVI, indicating a remarkable parasympathetic withdrawal. 3,[6][7][8]12,13 The GPs in the LA are located close to the selected CPVI ablation trajectory 1 and, therefore, are commonly collaterally damaged during the ablation. 3,[6][7][8]12,13 Clinical studies showed a significantly higher number of cases free of AF after CPVI in patients who exhibited a more pronounced postablation change in the HRV indices of parasympathetic denervation.…”

“…3,6,7 A long -term pattern of CA -related cardiac denervation (and subsequent reinnervation) is underreported and currently available data are conflicting. 3,[6][7][8] We studied the pattern of longitudinal changes in heart rate variability (HRV; as a measure of cardiac denervation) after CPVI for PAF as well as the relationship between the post -CPVI change in HRV and long -term freedom from AF.…”

The absence of effect of ganglionated plexi ablation on heart rate variability parameters in patients after thoracoscopic ablation for atrial fibrillation

“…The ablation of the ganglionated plexuses (GPs) was done in this aforementioned sequence in all patients. Each GP received at least 5 RF applications (30 s, [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35] Watts according to the ablation site) with a mean RF time of 4.6±2.3 min. Next the sheath was withdrawn to the right atrium, a 20-polar hallo catheter was added, and an ablation of the cavotricuspid isthmus was performed.…”