Predictors of first pass isolation of the pulmonary veins in real world ablations: An analysis of 2671 patients from the REAL‐AF registry

Abstract

IntroductionDuring atrial fibrillation ablation (AFA), achievement of first pass isolation (FPI) reflects effective lesion formation and predicts long‐term freedom from arrhythmia recurrence. We aim to determine the clinical and procedural predictors of pulmonary vein FPI.MethodsWe reviewed AFA procedures in a multicenter prospective registry of AFA (REAL‐AF). A multivariate ordinal logistic regression, weighted by inverse proceduralist volume, was used to determine predictors of FPI.ResultsA total of 2671 patients were included with 1806 achieving FPI in both vein sides, 702 achieving FPI in one, and 163 having no FPI. Individually, age, left atrial (LA) scar, higher power usage (50 W), greater posterior contact force, ablation index >350 posteriorly, Vizigo™ sheath utilization, nonstandard ventilation, and high operator volume (>6 monthly cases) were all related to improved odds of FPI. Conversely sleep apnea, elevated body mass index (BMI), diabetes mellitus, LA enlargement, antiarrhythmic drug use, and center's higher fluoroscopy use were related to reduced odds of FPI. Multivariate analysis showed that BMI > 30 (OR 0.78 [0.64–0.96]) and LA volume (OR per mL increase = 1.00 [0.99–1.00]) predicted lower odds of achieving FPI, whereas significant left atrial scarring (>20%) was related to higher rates of FPI. Procedurally, the use of high power (50 W) (OR 1.32 [1.05–1.65]), increasing force posteriorly (OR 2.03 [1.19–3.46]), and nonstandard ventilation (OR 1.26 [1.00–1.59]) predicted higher FPI rates. At a site level, high procedural volume (OR 1.89 [1.48–2.41]) and low fluoroscopy centers (OR 0.72 [0.61–0.84]) had higher rates of FPI.ConclusionFPI rates are affected by operator experience, patient comorbidities, and procedural strategies. These factors may be postulated to impact acute lesion formation.

How to improve the efficacy of point‐by‐point radiofrequency ablation

“…As stated by the authors, a conservative setting in the posterior wall, that is very low contact force (less than 10 g) and very low AI target (<350), produced a negative impact on acute success of radiofrequency ablation. 10 This should induce operators to overcome the concerns of esophageal heating while ablating along the posterior segments. On the contrary, higher AI targets (>380) on the posterior wall did not increase the rate of first-pass isolation and did not decrease the rate of late PVs reconnection.…”