Head-to-head comparison of two atrial fibrillation driver mapping systems for additional ablation in persistent atrial fibrillation: The CONTROL-AF trial

AIMS This randomized study seeks to elucidate the efficacy of additional ablation strategies using the CARTOFINDER™ or ExTRa Mapping™ system which identify focal or rotational activation during atrial fibrillation(AF) rhythm. METHODS AND RESULTS A total of 80 patients who underwent initial catheter ablation for persistent AF and whose AF was persistent even after both CARTOFINDER™ or ExTRa Mapping™ in both atrium following pulmonary vein isolation were randomly assigned in a 1:1 ratio to the CARTOFINDER™-guided focal activation ablation group(FINDER group) or the ExTRa Mapping™-guided substrate homogenization group(ExTRa group). The primary outcome measure was recurrent atrial tachyarrhythmias after a 90-day blanking period post ablation procedure. A total of 2954 sites in both atria of 80 patients were assessed by both mapping systems. CARTOFINDER™ identified focal activations in 51.5%. of the sites, whereas ExTRa Mapping™ identified rotational activation in 33.1% of the sites, based on a high non-passively activated ratio (%NP). The 1-year event free survival from atrial tachyarrhythmia recurrence was numerically lower in the FINDER group than the ExTRa group(65.0% versus 80.0%, Log-rank P = 0.14). By multivariable analysis, a left atrial volume ≥ 150 ml(HR3.27, 95%CI1.26-9.13, P = 0.02) and low voltage(<0.25 mV) during AF rhythm(HR3.68, 95%CI1.12-13.3, P = 0.03), and CARTOFINDER™-guided focal activation ablation relative to ExTRa Mapping™-guided homogenization(HR2.84, 95%CI1.06-7.07, P = 0.03) were identified as independent risk factors for post-procedure recurrent atrial tachyarrhythmias. CONCLUSIONS While the difference of atrial tachyarrhythmia recurrence in persistent AF patients did not reach statistical significance, CARTOFINDER™-guided focal activation ablation beyond PVI might be less effective than ExTRa mapping™-guided substrate homogenization.