Response to "Detection of oesophageal course during left atrial ablation".

We would like to thank the colleagues who have submitted a letter to the editor in response to our strategy to detect Oesophageal (OE) course during catheter ablation, described in our recent paper, “detection of oesophageal course during left atrial catheter ablation” [1]. The Impact study showed that a temperature control device (ensoETM, Attune Medical, Chicago IL) is a safe and feasible methodology to avoid atrio-oesophageal fistula during left atrial catheter ablation [2]. In our study, the use of the Cartosound reconstruction do not quantify the temperature in the OE. It permits to obtain position and relationship of the OE with left atrial posterior wall. Our method underlined one of a lot of the uses of the Cartosound module. We use the intracardiac echocardiography and Cartosound module to obtain left atrial and veins anatomy to navigate under a glass view into the left atrium after transeptal puncture, to perform transeptal puncture, to monitoring the pericardium and to detect the course of the OE. A variety of OE imaging features, including whether filled with gas, fluid or both, movement within its segment or variably collapsed lumen, may help to identify the OE with real-time 2D ICE and a fixed 3D Cartosound reconstruction, while monitoring during the LA ablation procedure. We did not use general anesthesia, so once the procedure begins, the OE location and anatomical characteristics should be relatively recognizable, making the patient swallow during the visualization of the OE along its entire journey. The OE reconstruction could be integrated with ensoETM device to improve the safety of the left atrial ablation. Main limitation to Cartosound approach was the absence of the temperature monitoring during catheter ablation. The limitation to use of the OE probe could be the conscious sedation without endotracheal intubation. Since November 2020, in our EP Lab, we start to use the Dexmedetomidine beyond other drugs (like fentanyl and bolus of midazolam) to improve patient's comfort and conscious sedation during prolonged catheter ablation. Our preference is to perform the catheter ablation without endotracheal intubation. Besides in our study, the use of the catheter in OE determined discomfort, nausea and movements of the patients that could affect the accuracy of the merged EAM/ICE map and prolong CA duration procedure. We will wait for other studies about ensoETM or orogastric probe, with the contemporary Cartosound module, under conscious sedation, to improve the safety about OE protection of thermal injury during left atrial ablation.