Visualization of Real-Time Esophageal Location Using Intracardiac Echocardiography on a Three-Dimensional Mapping System: Comparison of Esophageal Location Using Preoperative Computed Tomography and Investigation of Predictors for Esophageal Movement During Catheter Ablation

Introduction: Pulmonary vein isolation (PVI) using radiofrequency catheter ablation is an effective treatment for atrial fibrillation; however, esophageal-related complications remain a concern. The first objective of this study was to compare the feasibility of two techniques for visualizing real-time esophageal images: intracardiac echocardiography (ICE-Eso) and preoperative computed tomography (CT-Eso). The second objective was to clarify the predictors of esophageal movement on the day of catheter ablation. Methods and Results: Eighty consecutive patients were included in this study. The esophageal location was measured at the centerline of each image on three equally separated imaging sections (upper, middle, and lower sites). Esophageal locations detected on ICE-Eso and CT-Eso were compared with those on contrast esophagography. We also investigated predictors of esophageal movement. A significant difference was found between the two distances in all three sections: upper site (ICE-Eso: 2.5 [interquartile range (IQR) 1.4–3.6] mm vs. CT-Eso: 5.2 [IQR 3.4–7.6] mm, p < 0.001), middle site (ICE-Eso: 2.7 [IQR 1.3–4.3] mm vs. CT-Eso: 5.4 [IQR 3.2–8.3] mm, p < 0.001), and lower site (ICE-Eso: 2.8 [IQR 1.2–5.2] mm vs. CT-Eso: 5.8 [IQR 3.1–10.3] mm, p < 0.001). Multivariate analysis revealed that eating a meal on the morning on the day of catheter ablation (non-fasting) was a predictor of esophageal movement. One patient (1.2%) experienced gastric hypomotility, which resolved completely with medical treatment. Conclusion: The results showed that ICE-Eso provided real-time, accurate esophageal location compared to CT-Eso. Therefore, ICE-Eso-guided PVI on the left atrial posterior wall near the esophagus may be a safe method. Additionally, non-fasting on the day of catheter ablation could help to predict esophageal movement.