RESUMO
BACKGROUND: It is common practice to empirically limit the radiofrequency (RF) power when ablating the posterior left atrium during atrial fibrillation ablation to avoid thermal injury to the esophagus. The objective of this study was to determine whether RF energy delivery limited by luminal esophageal temperature (LET) monitoring is associated with a reduction in esophageal injury compared with a strategy of RF power limitation alone. METHODS AND RESULTS: Eighty-one consecutive patients who underwent atrial fibrillation ablation followed by esophageal endoscopy were included in this observational study. All patients underwent extraostial electric pulmonary vein isolation by using an electroanatomic mapping system and irrigated RF ablation. All RF applications on the posterior left atrium were limited to 35 W. A commercially available, single-thermocouple esophageal probe was used to monitor LET in a subset of patients (n=67). In these cases, applications were promptly interrupted when LET was > or =38.5 degrees C; further applications were performed at reduced power to obtain a LET < 38.5 degrees C. Esophageal endoscopy was performed 1 to 3 days after the procedure. Ablation-related esophageal ulcerations were identified in 9 of 81 (11%) patients. All patients were asymptomatic. Of these 81 patients, LET monitoring during ablation occurred in 67 (83%) of patients. Esophageal injury was observed more frequently (36% versus 6%, P<0.006) in the group without LET monitoring. CONCLUSIONS: These data suggest that LET monitoring may be associated with a reduction in esophageal injury compared with power limitation alone.
