Is electrical cardioversion independently associated with infarcts on brain magnetic resonance imaging or clinical outcomes in patients with atrial fibrillation?

Abstract

Background: Electrical cardioversion (ECV) is frequently performed in symptomatic atrial fibrillation.

Objective: This study aimed to assess the association of ECV with infarcts on brain magnetic resonance imaging (bMRI) and clinical outcomes.

Methods: The Swiss Atrial Fibrillation Cohort Study included 2386 patients; 1731 patients were evaluated by bMRI. ECVs were recorded by questionnaire. Patients were assigned to categories by number of ECVs performed before enrollment (0, 1, ≥2). A bMRI study was conducted at baseline and after 2 years (n = 1227) and analyzed for large noncortical or cortical infarcts and small noncortical infarcts. Clinical outcomes were recorded during follow-up. Associations of ECV and outcome measures were assessed by multivariate analyses.

Results: There was no independent association between the number of ECVs and infarct prevalence (large noncortical or cortical infarcts and small noncortical infarcts) on baseline bMRI (ECV 1 vs 0: odds ratio [OR], 0.95 [95% CI, 0.68-1.24]; ECV ≥2 vs 0: OR, 1.04 [0.72-1.44]) or between ECVs performed during follow-up and new infarcts on bMRI at 2 years (OR, 1.46 [0.54-3.31]). ECVs were not associated with overt stroke or transient ischemic attack (ECV 1 vs 0: hazard ratio [HR], 1.36 [0.88-2.10]; ECV ≥2 vs 0: HR, 1.53 [0.94-2.48]), hospitalization for heart failure (ECV 1 vs 0: HR, 1.06 [0.82-1.37]; ECV ≥2 vs 0: HR, 1.03 [0.77-1.38]), or death (ECV 1 vs 0: HR, 0.90 [0.70-1.15]; ECV ≥2 vs 0: HR, 0.91 [0.69-1.20]).

Conclusion: There was no association between ECV performed before enrollment and cerebral infarcts on baseline bMRI or between ECV performed during follow-up and new infarcts at 2 years. Moreover, ECV was not associated with clinical events.