Electrical and Thermal Effects of Esophageal Temperature Probes on Radiofrequency Catheter Ablation of Atrial Fibrillation: Results from a Computational Modeling Study

Abstract

Luminal esophageal temperature (LET) monitoring is commonly employed during catheter ablation of atrial fibrillation (AF) to detect high esophageal temperatures during radiofrequency (RF) delivery along the posterior wall of the left atrium. However, it has been recently suggested that in some cases the esophageal probe itself may serve as an RF ‘antenna’ and promote esophageal thermal injury. In this study, we developed a computational model to assess the electrical and thermal effects of three different types of esophageal temperature probes (ETPs): a standard single-sensor and two multi-sensor probes (one with and one without metallic surfaces). Results showed that LET monitoring invariably underestimated the maximum temperature reached in the esophageal wall. While only the ETP with a metallic surface produced minimal electrical alterations, the magnitude of this interference did not appear to be clinically-significant. In conclusion, temperature rises in both the esophageal wall and the ETP seem to be primarily produced by thermal conduction, and not electrical and/or thermal interactions between the ablation catheter and the ETP, itself. As such, the proposed notion of the ‘antenna effect’ producing satellite esophageal lesions during AF ablation was not evident in this study.KeywordsAtrial fibrillationcomputer modelingesophageal injuryradiofrequency ablationtemperature monitoring