Left Atrial Calcification After Atrial Fibrillation Ablation Predicts Long-term Risk of Heart Failure Hospitalization

BackgroundLeft atrial calcification (LAC) after atrial fibrillation (AF) ablation has recently been described, but its clinical significance and determinants remain insufficiently defined. MethodsAmong 1,741 patients who underwent first-time radiofrequency AF ablation between 2011 and 2018, 231 patients underwent both pre- and post-ablation chest CT. Patients were classified into an LAC group (n=71) and a non-LAC group (n=160). Baseline characteristics, ablation parameters, and calcification sites were analyzed. Independent predictors of LAC formation were identified using Cox proportional hazards models. Clinical outcomes, including heart failure (HF) hospitalization, stroke, and a composite endpoint of all-cause mortality, HF, stroke, or coronary intervention, were compared during long-term follow-up. ResultsOver a mean follow-up of 9.5 {+/-} 2.7 years, LAC was detected in 31% of patients, typically 7.3 {+/-} 3.1 years after ablation. LAC occurred most frequently at the lateral mitral annulus and right pulmonary veins. Independent predictors of LAC formation were non-paroxysmal AF (HR 1.7, 95% CI 1.0-2.8, p=0.04), LA diameter >50 mm (HR 2.7, 95% CI 1.3-5.5, p<0.01), and ablation beyond the pulmonary veins (HR 2.3, 95% CI 1.3-4.2, p=0.04). Kaplan-Meier analysis showed significantly higher HF hospitalization in the LAC group (log-rank p=0.02), while stroke incidence was similar between groups (p=0.50). The composite endpoint occurred more frequently in the LAC group (p=0.05). ConclusionLAC is a not uncommon late finding after AF ablation, particularly in patients with advanced atrial remodeling or extensive ablation. Its presence is associated with a higher risk of HF hospitalization, underscoring the importance of procedural planning and long-term imaging surveillance in AF ablation patients.