B-PO03-110 ANATOMIC LESION LOCATION DURING PULMONARY VEIN ISOLATION IMPACTS ABLATION PARAMETERS AND INDEPENDENTLY PREDICTS IMPEDANCE CHANGE AND REGIONAL FIRST PASS ISOLATION: AN ANALYSIS OF 8395 LESIONS

Abstract

Left atrial regional anatomic and energy delivery variation may contribute to differences in ablation lesion characteristics and need for touchups. Evaluate the effect of lesion location on ablation parameters, impedance drop, and RFPI. We reviewed 73 ablation index (AI) guided AFA procedures uploaded to CARTONET for analysis. Eleven distinct anatomic regions were defined and touch-up lesions identified. A total of 8395 PVI lesions from 73 AFAs were analyzed. Lesion parameters differed significantly between regions with p< 0.01 for each parameter (Table 1). The right pulmonary vein isolation (PVI) lesions had higher CF, shorter duration, higher FTI, improved stability, and higher AI than the left ( p< 0.01 all comparisons). Despite this we observed lower impedance drops and RFPI (p< 0.01). In the right PVI, touchups were most common along the posterior wall (20.5%) and roof (13.5%). For the left they occurred along the ridge (11.1%) and posterior wall (8.8%). Multivariate analysis showed that location was a significant predictor of impedance drop even after accounting for effects of differing mean and minimum: stability, CF, duration, power, FTI or AI. Similarly, despite accounting for these variables and number of lesions, the inferior regions had lower odds of touch-up (Table 1). Significant regional variation exists in ablation CF, duration, power, and stability. Location is predictive of impedance drop and RFPI even after accounting for these parameters, suggesting regional effects independent of these indices. An ideal ablation strategy is adapted to address these differences.