Main findings
The present study evaluated the clinical characteristics and electrical features of focal activations associated with AF drivers using the CARTOFINDER, a novel mapping system for patients with persistent AF. We identified the following important features of the focal activation. Most CL of the focal activations were > 120 ms, which is greater than the value associated with CFAE,15 and demonstrated regularity with shorter CLSD. The intensity of focal activation was significantly correlated with the regularity of the CL with a shorter CLSD. Focal activations were typically observed in normal voltage regions and proximal to the CFAE area, but not within the CFAE area. The elimination of DFAs resulted in higher achievement of the composite endpoint during ablation. To the best of our knowledge, this is the first study to use DCL and DFAs to identify the dominant area of AF by using the novel mapping system CARTOFINDER.