Introduction: Pulmonary vein isolation (PVI) using high-power-short-duration (HPSD) radiofrequency ablation (RF) is emerging as the standard of care for treatment of atrial fibrillation (AF). While procedural short-term to midterm efficacy and efficiency are very promising, this registry aims to investigate esopahgeal safety using an optimized ablation approach.Methods: In a single-center experience, 388 consecutive standardized first-time AF ablation were performed using a CLOSE-guided-fixed-50 W-circumferential PVI and substrate modification without intraprocedural esophageal temperature measurement. Three hundred patients underwent postprocedural esophageal endoscopy to diagnose and grade endoscopically detected esophageal lesions (EDEL) and were included in the analysis.Results: EDEL were detected in 35 of 300 patients (11.6%), 25 of 35 were low-grade Kansas-city-classification (KCC) 1 lesions with fast healing tendencies. Six patients suffered KCC 2a lesions, 4 patients had KCC 2b lesions (1.3% of all patients). No esophageal perforation or fistula formation was observed. Patient baseline characteristics, especially patients age, gender, and body mass index did not influence EDEL incidence. Additional posterior box isolation did not increase the incidence of EDEL. In patients diagnosed with EDEL, mean catheter contact force during posterior wall ablation was higher (11.9 ± 1.8 vs. 14.7 ± 3 g, p < .001), mean RF duration was shorter (11.9 ± 1 vs. 10.7 ± 1.2 s, p < .001), while achieved ablation index was not different between groups (434 ± 4.9 vs. 433 ± 9.5, n.s.). Conclusion:Incidence of EDEL after CLOSE-guided-50 W-HPSD PVI is lower compared to historical cohorts using standard-power RF settings. Catheter contact force during posterior HPSD ablation should not exceed 15 g.