Association of extra-pulmonary vein triggers with low-voltage area and clinical recurrence in patients with atrial fibrillation undergoing catheter ablation

Background and Objectives: Although extra-pulmonary vein (PV) triggers (ExPVTs) play a role in atrial fibrillation (AF) recurrence after catheter ablation (AFCA), the mechanism is unknown. We explored whether the locations of ExPVTs were associated with low-voltage scar areas (LVAs). Methods: Among 2255 consecutive patients who underwent a de novo AFCA, 1696 (male 72.1%, median 60 years old, paroxysmal 64.7%) were included who underwent isoproterenol provocation and voltage mapping of the left atrium (LA) during their procedures. We investigated the associations between ExPVTs and their mean LA voltage and colocalization of ExPVTs within LVAs (<0.2 mV). Results: We observed ExPVTs in 181 (10.7%) patients (60 in the LA, 99 in the right atrium [RA], 16 biatrial, and 6 unmappable). A lower mean LA voltage was independently associated with the existence of ExPVTs (OR 0.77 per 1 SD mV increase, 95% CI 0.60-0.99, p = .039). Among 76 patients who had ExPVTs[LA], 43 (56.6%) had ExPVTs within LVAs. During a median of a 42-month follow-up, patients with ExPVTs had a higher AF recurrence than those without (HR 1.87, 95% CI 1.48-2.37, Log-rank p < .001), but colocalization of ExPVTs and LVAs (Log-rank p = .544) and the anatomical location of ExPVTs (Log-rank p = .084) did not affect the rhythm outcome. Conclusions: The presence of ExPVTs was associated with low LA voltage and poor rhythm outcome post-AFCA, but the colocalization of ExPVTs and LVA in LA did not affect rhythm outcome.