Introduction: In addition to symptomatic improvement, catheter ablation (CA) of atrial fibrillation (AF) improves left ventricular systolic function and functional capacity when performed in selected patients with heart failure. The impact of CA on long term outcome in the heart failure cohort is poorly understood. Furthermore, the impact of early ablation for all patients versus a delayed selective strategy is unknown.
Methods: ARC-HF and CAMTAF were two similar UK single centre RCTs performed between 2006-2012. Both enrolled patients with persistent AF, symptomatic HF and left ventricular systolic dysfunction. Patients were randomised to CA or medical rate control and studied for 12 months. Subsequent to the study period patients underwent CA as clinically indicated. Contemporary longitudinal follow-up of patients enrolled in these trials was performed to determine the long-term outcomes. The primary outcome was a comparison of the long-term mortality in the two groups using multi-variate Cox regression analysis. The need for repeat CA was also assessed.
Results: 102 patients were included, with a mean age of 60 ± 11 years, 93 (91%) were male (Table 1). Baseline characteristics were similar between groups apart from small differences in baseline LV EF which was lower in the ablation versus medical therapy cohort (29.0 ± 8.7% vs 33.7 ± 12.0%, p=0.02). Mean follow-up was 7.0 ± 3.6 years. 29 (59.2%) patients initially randomised to the medical therapy cohort underwent AF CA after the trial period although median number of procedures remained lower over long-term follow-up (1 [0-2] vs 2 [1-2], p<0.01). 31 (30.4%) patients died during follow-up. Based on an intention to treat analysis, catheter ablation was not associated with a significant reduction in very long-term mortality after multi-variate analysis controlling for age and baseline LV EF (HR 0.81 [95% CI 0.39-1.67], p=0.57; Figure 1).
Conclusion: These long-term outcomes support the reasonable use of CA in selected patients with HF. Post-hoc follow-up after trial completion coupled with therapeutic crossover limits direct comparison of the two treatment pathways on an intention-to-treat analysis. However, these data suggest that an early ablation strategy produces similar long-term outcomes to a delayed selective approach to ablation in patients with persistent AF and heart failure.
