Prognostic value of cardiac deceleration capacity in patients with atrial fibrillation after catheter ablation: A systematic review and meta-analysis

Background: Cather ablation (CA) is a well-recognized treatment alternative for atrial fibrillation (AF) patients despite more than 20% ablation-treated patients suffering from AF recurrence. The underlying mechanism of AF recurrence post-ablation is probably associated with high cardiac parasympathetic activity, which can be assessed with deceleration capacity (DC) of heart rate. Given that the relationship between DC and AF recurrence is still controversial, this systematic review and meta-analysis was performed to investigate the characteristics of DC in patients with and without AF recurrence, evaluating the prognostic value of DC in AF patients after CA. Methods: A literature search was systematically performed in the Embase, PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), and Wanfang databases until October 01, 2023. The observational studies reporting either the pre- and post-ablation DC in both recurrence and non-recurrence groups or the ratios based on DC for predicting AF recurrence were mainly included. Weighted mean differences (WMD) or odds ratios (OR) based on DC would be calculated with a random-effect model, if heterogeneity estimated with the I index and Q statistic was significant ( I > 50% or P < .05); otherwise, a fixed-effect model would be utilized. Results: A total of 8 observational studies involving 914 AF patients treated with radiofrequency or cryoballoon ablation were included in this study. Ablation-treated patients with AF recurrence had the higher DC post-ablation in relation to those without recurrence (WMD, 1.00; 95%CI, 0.33 to 1.67; P < .01), which was present up to 3 months of follow-up (WMD, 1.54; 95%CI, 1.11 to 1.96; P < .01), whereas there was no statistical significance in DC prior to ablation between recurrence and non-recurrence groups (WMD, 0.34; 95%CI, -0.12 to 0.79; P = .15). The high DC post-ablation was a risk factor for AF recurrence in ablation-treated patients (OR, 2.17; 95%CI, 1.44 to 3.25; P < .01). Conclusion: The high DC post-ablation was associated with the risk of AF recurrence, suggesting that DC may act as a prognostic indicator in AF patients treated with CA. Keywords: Deceleration capacity; Atrial fibrillation; Catheter ablation; Recurrence; Meta-analysis; Systematic review.