Discrepancy between CARTO and Rhythmia maps for defining the left atrial low-voltage areas in atrial fibrillation ablation.

Reported mapping procedures of left atrial (LA) low-voltage areas (LVAs) vary widely. This study aimed to compare the PentaRay®/CARTO®3 (PentaRay map) and Orion™/Rhythmia™ (Orion map) systems for LA voltage mapping. This study included 15 patients who underwent successful pulmonary vein isolation (PVI) for atrial fibrillation. After PVI, PentaRay and Orion maps created for all patients were compared. LVAs were defined as sites with ≥ 3 adjacent low-voltage points < 0.5 mV. LVAs were indicated in 8 (53%) among 15 patients, and the average values of the measured LVAs was comparable between the systems (PentaRay map = 5.4 ± 8.7 cm2; Orion map = 4.3 ± 6.4 cm2, p = 0.69). However, in 2 of 8 patients with LVAs, the Orion map indicated LVAs at the septum and posterolateral sites of the LA, respectively, whereas the PentaRay map indicated no LVAs. In those patients, sharp electrograms of > 0.5 mV were properly recorded at the septum and posterolateral sites during appropriate beats in the PentaRay map. The PentaRay map had a shorter procedure time than the Orion map (12 ± 3 min vs. 23 ± 8 min, respectively; p < 0.01). Our study results showed a discrepancy in the LVA evaluation between the PentaRay and Orion maps. In 2 of 15 patients, the Orion map indicated LVAs at the sites where > 0.5-mV electrograms were properly recorded in the PentaRay map.