Long‐term outcomes of catheter ablation for atrial fibrillation: It's a matter of time

Abstract

Bristol-Myers Squibb, Pfizer, and Servier. All other others have nothing to disclose.Atrial fibrillation (AF) ablation is a minimally invasive rhythm control strategy aimed to restore sinus rhythm in symptomatic patients who are refractory to at least one antiarrhythmic drug (AAD). 1 To reduce the AF burden, AF ablation targets the arrhythmogenic substrate responsible for triggering and maintaining AF in the left atrium. 1 Several randomized trials have demonstrated that AF ablation reduces AF recurrences and improves quality of life when compared with AADs. 2 The efficacy and effectiveness of AF ablation to decrease the incidence of hard outcomes, such as all-cause mortality, stroke, and heart failure (HF) hospitalizations, however, is less consistent, especially for long-term follow up. 3 As AF ablation is increasingly utilized as a treatment option for patients with AF 4 and indications for its use are being widened to AF patients with additional comorbidities, 1 an understanding of the long-term effectiveness of AF ablation is warranted.In this issue of the Journal of Cardiovascular Electrophysiology, Saglietto et al 3 conducted a meta-analysis of randomized controlled trials and observational studies with greater than 2 years of follow up to specifically evaluate the association between AF ablation and allcause mortality, stroke, and HF hospitalizations. Only one randomized trial, catheter ablation versus antiarrhythmic drug therapy for atrial fibrillation (CABANA) trial, 5 and eight large observational studies were included (N = 241 372 patients) and study follow up ranged from 2.1 to 4 years. 3 After pooling the effect estimates with the random effects model, AF ablation was associated with a reduction in the incidence of all-cause mortality (hazard ratio [HR], 0.62 [95% confidence interval [CI], 0.54-0.72]), stroke (HR, 0.63 [95% CI, 0.56-0.70]), and HF hospitalization (HR, 0.64 [95% CI, 0.51-0.80]);which translates to a greater than 35% decrease for each individual event when treated with AF ablation compared with medical therapy. 3 Pooled effect estimates were primarily driven by the observational studies (weight of CABANA estimates between 0.7% and 10.7%). The degree of heterogeneity between pooled studies was low for stroke (I 2 = 23%) and HF hospitalizations (I 2 = 28%), however, there was substantial heterogeneity among estimates for all-cause mortality (I 2 = 54%). 3 The magnitude of heterogeneity (I 2 = 29%) and hazards for all-cause mortality (HR, 0.60 [95% CI, 0.53-0.67]) with AF ablation decreased when the treatment-received (HR, 0.60 [95% CI, 0.42-0.86]) rather than intent-to-treat (HR, 0.85 [95% CI, 0.60-1.21]) estimates for CABANA 5 were included in the random effects model reflecting that the treatment-received analysis more closely mimics the real-world observational estimates. In a meta-regression analysis, only advanced age was a predictor for reduced long-term effectiveness of AF ablation though important variables, such as left atrial size could not be assessed. 3 Overall, the meta-ana...