Mortality, stroke, and heart failure in atrial fibrillation cohorts after ablation versus propensity-matched cohorts

Abstract

BACKGROUND: We sought to determine from key clinical outcomes whether catheter ablation of atrial fibrillation (AF) is associated with increased survival. METHODS AND RESULTS: Using routinely collected hospital data, ablation patients were matched to two control cohorts using direct and propensity score methodology. Four thousand nine hundred ninety-one ablation patients were matched 1:1 with general AF controls without ablation. Five thousand four hundred seven ablation patients were similarly matched to controls who underwent cardioversion. We examined the rates of ischemic stroke or transient ischemic attack (stroke/TIA), heart failure hospitalization, and death. Matched populations had very similar comorbidity profiles, including nearly identical CHA2DS2-VASc risk distribution (p=0.6948 and p=0.8152 vs general AF and cardioversion cohorts). Kaplan-Meier models showed increased survival after ablation for all outcomes compared with both control cohorts (p<0.0001 for all outcomes vs general AF, p=0.0087 for stroke/TIA, p<0.0001 for heart failure, and p<0.0001 for death vs cardioversion). Cox regression models also showed improved survival after ablation for all outcomes compared with the general AF cohort (hazard ratio [HR]=0.4, 95% confidence interval [95% CI]: 0.3-0.6, p<0.0001 for stroke/TIA; HR=0.4, 95% CI: 0.2-0.6, p<0.0001 for heart failure; HR=0.1, 95% CI: 0.1-0.1, p<0.0001 for death) and the cardioversion cohort (HR=0.6, 95% CI: 0.4-0.9, p=0.0111 for stroke/TIA; HR=0.4, 95% CI: 0.3-0.6, p<0.0001 for heart failure; HR=0.3, 95% CI:0.2-0.5, p<0.0001 for death). CONCLUSIONS: Catheter ablation of AF was associated with very significant reductions in mortality, stroke/TIA, and heart failure compared with a matched general AF population and a matched population who underwent cardioversion. Potential confounding of outcomes was minimized by very tight cohort matching.