Heart failure and catheter ablation of atrial fibrillation: Navigating the difficult waters of heart failure phenotypes

The use of catheter ablation of atrial fibrillation (AFA) is increasing and it has now been extended to include higher risk patients with heart failure (HF), based on evidence from observational studies and meta-analyses of randomized controlled trials (RCTs) indicating it as safe and beneficial in terms of quality of life, AF recurrence and hospital readmissions in the short-to-middle term. However, the RCTs so far have been relatively small with short follow-up, and few larger trials with long follow-up inconclusive about hard outcomes for large patient crossover undermining the robustness of the results. Importantly, most RCTs involved HF patients with reduced left ventricular ejection fraction (HFrEF). In contrast, most observational studies show that the majority of ablated HF patients in clinical practice have a preserved ejection fraction (HFpEF), a condition representing roughly half of all HF patients. This article provides an overview of the available scientific evidence in this clinical field and examines the current guideline recommendations. In the absence of robust evidence-based research, the recommendations on AFA in HF may be inconsistent or abstain from taking firm positions, particularly regarding AFA in HFpEF. There is need for clinical research in such a surprisingly orphan setting, in parallel with the current attempts to sort out the knotty question of the HF phenotypes, in particular, again, of the HFpEF phenotypes.