The goal of pulmonary vein ablation for atrial fibrillation (AF) is returning to normal sinus rhythm; nevertheless it success is limited in part by uncertainly in the mechanisms that sustain AF. Intracardiac recordings from 43 AF patients were submitted to the ablation procedure and monitored after ablation. In order to predict AF recurrences dominant frequency of atrial activity was studied. The novelty of this study is that dominant frequency was calculated from reconstructed signal by singular spectrum analysis (SSA) application, this method showed to be more efficient in the case of very irregular and chaotic rhythm. Patients that maintained sinus rhythm and patients with recurrence in AF showed differences in left atrium dominant frequencies, with higher values in the recurrent AF group, 6.61±1.66 Hz than in the group without recurrence in the arrhythmia, 5.49±1.41 Hz (p=0.02). Moreover, differences between both atria were found in the non-recurrent group, with 5.76±1:31 Hz in the left atrium vs. 6.25±1.23 Hz in the right atrium (p=0.03). These findings show the potential to SSA as a preprocessing method to extract atrial activations from electrograms. Moreover, results are congruent with previous studies with a more rapid atrial activity along the left atrium in the patients with recurrences in AF.