EGF and atrial fibrillation: For these patients in whom FIRM‐guided ablation happened to eliminate the active source as determined by the post‐hoc EGF maps, 7 (63.6%) remained AF‐free at 1‐year post‐ablation compared with the 22 patients who ended the procedure with the final basket recording still showing an S‐type EGF signature on their post‐processed EGF maps and 86.4% developed recurrent AF within the year following the procedure (χ2p = .003).