Relationship between the Long-Term Result of PVI and Left Atrial Bipolar Voltage during AF Rhythm

Abstract

Background: Atrium scaring is associated with the result of pulmonary vein isolation (PVI) for the atrial fibrillation (AF). Previous reports have been the area or distribution of myocardium fibrosis correlated with the bipolar voltage map on sinus rhythm. We evaluated the relationship between the long-term result of PVI and left atrial bipolar voltage during AF rhythm as a left atrial substrate. Methods: Forty-six consecutive AF patients (61±10 years old, 31 males) from March to December in 2007 underwent electroanatomical mapping (CARTO) during AF prior to circumferential PVI, and were stored the mean peak-to-peak amplitude of the bipolar electograms as a voltage map. If needed, the multi-sessions including the substrate ablation were performed for the recurrence cases. We retrospectively observed the surface area and distribution of the low voltage zones (LVZ) changing cut-off limit from 0.1 mV to 0.8 mV and evaluated the extent of LVZ by counting the LVZ regions (LVZ score; 0–5) at baseline. Results: The mean LA volume was 116±35 ml. During the follow-up (mean; 28 months) 39 patients (84.7%) had no recurrence of AF without any anti-arrhythmic agents (AAAs). When we defined the LVZ areas as below 0.2 mV, the LVZ score correlated with clinical outcome (sensitivity 100%, specificity 87.2%, AUC 0.91). Conclusions: The distribution of the LVZs below 0.2 mV during AF associated the long-term outcome of the PV isolation.