Real-time dominant frequency mapping and ablation of dominant frequency sites in atrial fibrillation with left-to-right frequency gradients predicts long-term maintenance of sinus rhythm

BackgroundSpectral analysis identifies localized sites of high-frequency activity during atrial fibrillation (AF).ObjectiveThis study sought to determine the effectiveness of using real-time dominant frequency (DF) mapping for radiofrequency ablation of maximal DF (DFmax) sites and elimination of left-to-right frequency gradients in the long-term maintenance of sinus rhythm (SR) in AF patients.MethodsDF mapping was performed in 50 patients during ongoing AF (32 paroxysmal, 18 persistent), acquiring a mean of 117 ± 38 points. Ablation was performed targeting DFmax sites, followed by circumferential pulmonary vein isolation.ResultsAblation significantly reduced DFs (Hz) in the LA (7.9 ± 1.4 vs. 5.7 ± 1.3, P <.001), coronary sinus (CS) (5.7 ± 1.1 vs. 5.3 ± 1.2, P = .006), and RA (6.3 ± 1.4 vs. 5.4 ± 1.3, P <.001) abolishing baseline left-to-right atrial DF gradient (1.7 ± 1.7 vs. 0.2 ± 0.9; P <.001). Only a significant reduction in DFs in all chambers with a loss of the left-to-right atrial gradient after ablation was associated with a higher probability of long-term SR maintenance in both paroxysmal and persistent AF patients. After a mean follow-up of 9.3 ± 5.4 months, 88% of paroxysmal and 56% of persistent AF patients were free of AF (P = .02). Ablation of DFmax sites was associated with a higher probability of remaining both free of arrhythmias (78% vs. 20%; P = .001) and free of AF (88% vs. 30%; P <.001).ConclusionRadiofrequency ablation leading to elimination of LA-to-RA frequency gradients predicts long-term SR maintenance in AF patients.