Limitations
Our study was retrospective, leading to possible confusion bias. Nevertheless, we included all consecutive procedures in each group over the same period of time. The choice of the Rhythmiaâ„¢ system to guide ablation procedure was not randomized, and one could assume that our study population should be slightly different if all procedures were considered, regardless of the mapping system used. LVEF was not determined by a core-lab but was retrieved from medical files. We did not use a standardized arrhythmia recurrence diagnostic protocol and patients with HFrEF had more implanted device allowing asymptomatic recurrence documentation. Therefore, it would be important to address these biases and confirm our results in a prospective manner. Conversely, our study population is probably representative of the real-life ablation landscape in a setting of HF, with repeated ablations and recurrent ATs.