Risk Factors of Complications in Patients With Persistent or Long-Standing Persistent Atrial Fibrillation/Atrial Flutter Who Underwent Electrical Cardioversion: A Multicenter Cardioversion Registry

BACKGROUND: Identifying the risks related to the complications of electrical cardioversion (ECV) can alert the determinaton of rhythm control in patients with atrial fibrillation (AF). METHODS: We retrospectively reviewed 1,058 patients who underwent ECV for persistent or long-standing persistent AF/atrial flutter (AFL) from multiple centers. Patients were classified into the no-complication (1,023 patients) and complication (35 patients) groups based on the following major complications: stroke and/or systemic embolism (SSE), myocardial infarction, major bleeding, implantation of cardiac implantable electronic devices, ventricular tachycardia/fibrillation, and death at 1 year follow-up after ECV. RESULTS: Compared with the no-complication group, the complication group exhibited a higher proportion of female patients (37% vs. 22%), as well as a higher proportion of patients with older age (67 ± 11 vs. 61 ± 10 years), diabetes mellitus (DM) (49% vs. 24%), heart failure (HF) (49% vs. 30%), SSE (23% vs. 9%), high CHA₂DS₂-VASc (CV) score (3.6 ± 1.8 vs. 2.2 ± 1.4), low left ventricular ejection fraction (LVEF) (50 ± 16% vs. 58 ± 21%), and high left atrial volume index (LAVI) (51 ± 26 vs. 40 ± 20 mL/m²). Class I and III antiarrhythmics were less prescribed in the complication group than in the no-complication group (57% vs. 76%). Univariate analysis for complications revealed age (≥ 65 years), female sex, DM, HF, SSE, LVEF (< 50%), LAVI (≥ 40 mL/m²), CV score (≥ 3), bradycardia on Holter (< 60/min), and no antiarrhythmics as risk factors. Among these, multivariate analysis revealed clinical significance of female sex and SSE. CONCLUSION: Female sex and a history of SSE were the most important risk factors of complications in patients with persistent or long-standing persistent AF/AFL who underwent ECV.