Structural characteristics of patients with superior vena cava foci initiating atrial fibrillation: Analysis with electrocardiogram‐triggered computed tomography

Abstract

Introduction:The superior vena cava (SVC) is the most common source of nonpulmonary vein foci in atrial fibrillation (AF); therefore, predicting the existence of non-pulmonary vein foci before the catheter ablation procedure helps construct a proper ablation strategy in preparation for SVC isolation. This study aimed to clarify the structural characteristics of patients with SVC foci initiating AF. Methods:We enrolled 331 consecutive patients with AF who underwent cardiac computed tomography imaging before radiofrequency catheter ablation treatment, and they were divided into SVC (+) and (−) groups based on the presence or absence of SVC foci initiating AF. Results:The SVC (+) group (n = 27) exhibited SVC crescent signs-defined as a curve-shaped SVC with two narrow pointed ends-more frequently (37% vs. 9%, p < .001), and larger right atrial volume (95.6 ± 20.8 vs. 80.5 ± 26.1 mL, p = .004) than the SVC (−) group (n = 304). Multivariate logistic regression analysis revealed that the SVC crescent sign (odds ratio, 8.88; 95% confidence interval [CI], 3.21-24.60) and right atrial volume (odds ratio, 1.03; 95% CI, 1.01-1.04) were independent predictors of SVC foci. Conclusion:Patients with SVC foci exhibited more frequent SVC crescent signs and larger right atrial volumes, and these characteristics may help clinicians choose the appropriate ablation technology.