Lone atrial fibrillation ablation. Transcatheter or minimally invasive surgical approaches?

Atrial fibrillation (AF) is the most frequent supraventricular arrhythmia, and its therapy is still unsatisfactory. Different theories have been proposed to explain its mechanism. Nowadays it seems well accepted that both focal and re-entrant mechanisms are involved, playing a different role in the initiation and maintenance of the arrhythmia. Moreover, the importance of each mechanism varies in patients with different etiologies of the arrhythmia. The presence of atrial foci functioning as triggers, generally localized in the pulmonary veins (PVs), is the main finding in patients with lone or idiopathic AF. In this patient population, the focal ablation of AF has been shown to be quite effective. In contrast, in patients with chronic AF and valvular heart disease associated with concomitant pathologic atrial modifications, the ablation of the atrial foci is less effective. It seems reasonable to suppose that in patients with chronic AF an abnormal substrate with short and nonhomogeneous conduction properties plays a more important role than the trigger foci.