Procedural efficacy and safety of standardized, ablation index guided fixed 50 W high-power short-duration pulmonary vein isolation and substrate modification using the CLOSE protocol

INTRODUCTION

Ablation index (AI)-guided ablation according to the CLOSE protocol is very effective in terms of chronic pulmonary vein isolation (PVI). However, the optimal radiofrequency (RF) power remains controversial. Here, we thought to investigate the efficiency and safety of an AI-guided fixed circumferential 50 W high-power short-duration (HPSD) PVI using the CLOSE protocol.

METHODS AND RESULTS

In a single-center trial, 40 patients underwent randomized PVI using AI-guided ablation without esophageal temperature monitoring. In 20 patients a CLOSE protocol guided fixed 50 W HPSD was followed irrespective of the anatomical localization. Twenty subjects were treated according to the CLOSE protocol with standard power settings (20 W posterior and 40 W roof and anterior wall). In addition, 80 consecutive patients were treated according to the HPSD protocol to gather additional safety data. All patients underwent postprocedural esophagogastroduodenoscopy to reveal esophageal lesions (EDELs). The mean total procedural time was 80.3 ± 22.5 in HPSD compared to control 109.1 ± 27.4 min (p < .001). The total RF-time was significantly lower in HPSD with 1379 ± 505 s versus control 2374 ± 619 s (p < .001). There were no differences in periprocedural complications. EDEL occurred in 13% in the HPSD and 10% in the control group. EDEL occurring in the 50 W HSDP patients were smaller, more superficial, and had a faster healing tendency.

CONCLUSION

A fixed 50 W HPSD circumferential PVI relying on the AI and CLOSE protocol reduce the total procedure time and the total RF time, without increasing the complication rates. The incidence of EDELs was similar using 50 W at the posterior atrial wall.

Temperature monitoring and temperature-driven irrigated radiofrequency energy titration do not prevent thermally induced esophageal lesions in pulmonary vein isolation: A randomized study controlled by esophagoscopy before and after catheter ablation

BACKGROUND

Endoscopically detected esophageal lesions (EDELs) are common following pulmonary vein isolation (PVI) and may progress to atrioesophageal fistula (AEF).

OBJECTIVE

The purpose of this study was to study (1) the benefit of luminal esophageal temperature (LET) monitoring and (2) the impact of esophagogastroduodenoscopy (EGD) in detecting EDEL and defining pre-existing lesions. The primary endpoint was the number of ablation-induced lesions.

METHODS

Patients with atrial fibrillation were randomized to PVI with LET monitoring (LET[+]) or without LET monitoring (LET[-]). All patients underwent EGD before and after PVI. Ablation power at the left atrial (LA) posterior wall was limited to 25 W in all patients and was titrated to a minimum of 10 W guided by esophageal temperature in the LET[+] group.

RESULTS

Eighty-six patients (age 67 ± 10 years; 57% male) were included (44 LET[+], 42 LET[-]). PVI was achieved in all, and additional linear LA lesions were done in 50%. Eight patients developed EDEL (6 LET[+], 2 LET[-]; P = NS). Whereas LET <41°C did not differentiate with regard to EDEL formation, temperature overshooting ≥42°C was associated with a higher risk for new EDEL. Two-thirds of patients showed incidental findings (esophagitis, gastric ulcer) on preprocedural EGD; 8 esophageal lesions were pre-existing. Four patients in the LET[+] group developed epistaxis following insertion of the probe.

CONCLUSION

Monitoring of LET does not prevent ablation-induced esophageal lesions. Patients without temperature surveillance were not at higher risk, but temperatures ≥42°C were associated with increased likelihood of mucosal lesions.

Relevance of esophageal position and temperature on thermal injuries and rhythm outcome in atrial fibrillation ablations

BACKGROUND

Thermolesions are a dangerous complication of atrial fibrillation (AF) ablation. We aimed to assess the reasons for thermolesions and the effect of esophageal position on recurrences.

METHODS

The study included consecutive patients undergoing AF catheter ablation at Heart Center Leipzig between January and September 2014. We collected data of esophagus localization, temperature, endoscopy, and follow-up.

RESULTS

The study included 645 patients into analyses. A total of 626 (97.2%) received a temperature probe. Esophageal position was categorized: (A) behind left pulmonary veins, (B) left ostial, (C) in the middle of left atrium, (D) right ostial, and (E) behind right pulmonary veins. The most frequent esophageal position was B-C (n = 201, 32.1%), followed by B (n = 161, 25.7%), and C (n = 147, 23.5%). The temperature was highest in A-B positions (42.04°C) and in D-E positions (41.70°C). There was a significant correlation between the endoscopically detected esophageal lesions (EDEL) and the esophageal position (r² = -.115, P = .004) and the esophageal temperature (r² = .162, P = .000), but not with body mass index (BMI) (r² = -.016, P = .688). Additional substrate modification in the left atrium resulted in significantly higher esophageal temperatures (P < .001) and more frequent EDEL (P = .049). An EDEL was found in 15 patients (2.3% of all patients, 5.6% of patients receiving endoscopy). Of those, the median esophageal temperature was 41.8°C (interquartile range [IQR]: 41.2-42.4). Neither esophageal position nor temperature during ablation was associated with arrhythmia recurrences (both P > .400).

CONCLUSIONS

EDEL depended on the esophageal position and temperature, but not on BMI. Esophageal position and intraluminal temperature during ablation had no effect on recurrences.