Comparative study of strategies to prevent esophageal and periesophageal injury during atrial fibrillation ablation

Autor: Barbara Oliveira, Conrado Balbo, Cristiano Pisani, Mauricio Scanavacca
Rok vydání: 2020
Předmět:
DOI: 10.22541/au.159170229.90318744
Popis: We thank Dr Shah and colleagues for their interest, analysis of the presented data and comments related to our paper1. Circumferential PV isolation using 8mm tip catheter is still currently used in our institution for some patients due to economic reasons, so we can provide AF ablation for a portion of the population for whom there is no private insurance available, with adequate safety and results (recurrence rate in this series was 15.6% in a follow-up of 11±5 months)2. Those catheters have two temperature sensors, thus reducing the risk of clot formation on the tip of the catheter. For the same reason, our institutional standard when using such catheters is to deliver RF applications in temperature-controlled mode with maximum temperature of 55oC. This mode of RF application is different compared to irrigated tip catheters and the mode of application used in the cited experimental study mentioned by the authors, in which it was used power-controlled RF applications.3 Due to the temperature-controlled mode of RF application, the cooling of esophagus generates a convective cooling of the atrial wall close to the esophagus and the catheter interface, leading to the higher power RF application that was observed in Group III.2 Probably due to this higher power of application, there was a higher rate of esophageal and periesophageal lesions injuries in the esophageal cooling group. This rate was however acceptable, since we used esophagogastroduodenoscopies (EGD) combined with radial endosonographies (EUS), that is a high sensitivity method of screening for esophageal lesion. Additionally, there were no severe or clinically significant lesions in any of the patients. A prior experimental model we performed some years ago also suggests this hypothesis.4 This model was similar to the one used by Montoya and cols3 and we could find deeper lesions with esophageal cooling and temperature-controlled applications, but similar depth, when power-controlled applications were performed.4 In silico models could also be used to evaluate the different effects of esophageal cooling using temperature or power-controlled RF applications. So, we think that the flow used in our studied balloon was not the reason for the findings, but the mode of application, although even in the esophageal cooling group the incidence of lesions was low. This was a prototype balloon used for the first time in clinical studies, and it was not possible to measure inflow and outflow temperature, being not possible to define heat transfer capacity. However, as presented before, as there was a higher RF power in group III we can infer that we achieved some cooling on the esophagus-atrium interface. Tsuchiya and cols showed a reduction in luminal esophageal temperature using an esophageal balloon with irrigation flow similar to our study.5We strongly agree with the authors that a higher flow of irrigation and consequential higher temperature reduction could be more protective, especially using power-controlled RF applications. Additionally, we think that esophageal cooling strategies are a promising strategy to avoid severe esophageal lesions, especially with contact sensor, power-controlled RF applications, allowing more effective atrial lesions close to the esophagus, thus improving AF ablation results. References 1. Shah S, Mercado Montoya M, Zagrodzky J, Kulstad E. Letter to the Editor regarding the paper "Comparative study of strategies to prevent esophageal and periesophageal injury during atrial fibrillation ablation". Journal of Cardiovascular Electrophysiology. 2020.2. de Oliveira BD, Oyama H, Hardy CA, et al. Comparative study of strategies to prevent esophageal and periesophageal injury during atrial fibrillation ablation. J Cardiovasc Electrophysiol. 2020;31(4):924-933.3. Montoya MM, Mickelsen S, Clark B, et al. Protecting the esophagus from thermal injury during radiofrequency ablation with an esophageal cooling device. J Atr Fibrillation. 2019;11(5):2110.4. Scanavacca MI, Neto S, Pisani CF, et al. Cooled intra-esophageal balloon to prevent thermal injury of esophageal wall during radiofrequency ablation. Heart rhythm. 2007;4(5):S117.5. Tsuchiya T, Ashikaga K, Nakagawa S, Hayashida K, Kugimiya H. Atrial fibrillation ablation with esophageal cooling with a cooled water-irrigated intraesophageal balloon: a pilot study. J Cardiovasc Electrophysiol. 2007;18(2):145-150.
Databáze: OpenAIRE
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