Incidence of acute thermal esophageal injury after atrial fibrillation ablation guided by prespecified ablation index

Machine learning identifies esophageal luminal temperature patterns associated with thermal injury in catheter ablation for atrial fibrillation

INTRODUCTION

Luminal esophageal temperature (LET) monitoring during atrial fibrillation (AF) ablation is widely used to reduce the incidence of endoscopically detected esophageal lesion (EDEL). We sought to assess whether specific patterns of LET variation are associated with EDEL.

METHODS

A high-fidelity multisensor probe was used to record LET in AF patients undergoing radiofrequency ablation (RFA) or cryoballoon ablation (CBA). Explainable machine learning and SHapley Additive exPlanations (SHAP) analysis were used to predict EDEL and assess feature importance.

RESULTS

A total of 94 patients (38.3% persistent AF, 71.3% male, 72 RFA, and 22 CBA) were included. EDEL was detected in 11 patients (10 RFA and one CBA). In the RFA group, the highest LET recorded was similar between patients with and without EDEL (40.6 [40.1-41]°C vs. 40.2 [39.1-40.9]°C; p = .313), however, the rate of LET rise for the highest recorded peak was higher (0.08 [0.03-0.12]°C/s vs. 0.02 [0.01-0.05]°C/s; p = .033), and the area under the curve (AUC) for the highest peak was smaller (412.5 [206.8-634.1] vs. 588.6 [380.4-861.1]; p = .047) in patients who had EDEL. In case of CBA, the patient with EDEL had a faster LET decline (0.12 vs. 0.07 [0.02-0.14]°C/s), and a smaller AUC for the lowest trough (2491.3 vs. 2629.3 [1712.6-5283.2]). SHAP analysis revealed that a rate of LET change higher than 0.05°C/s and an AUC less than 600 were more predictive of EDEL in RFA.

CONCLUSION

The rate of LET change and AUC for the recorded temperature predicted EDEL, whereas absolute peak temperatures did not.

Pulsed field ablation using focal contact force-sensing catheters for treatment of atrial fibrillation: acute and 90-day invasive remapping results

AIMS

Pulsed field ablation (PFA) has emerged as a promising alternative to thermal ablation for treatment of atrial fibrillation (AF). We report performance and safety using the CENTAURI™ System (Galvanize Therapeutics) with three commercial, focal ablation catheters.

METHODS AND RESULTS

ECLIPSE AF (NCT04523545) was a prospective, single-arm, multi-centre study evaluating safety and acute and chronic pulmonary vein isolation (PVI) durability using the CENTAURI System in conjunction with the TactiCath SE, StablePoint, and ThermoCool ST ablation catheters. Patients with paroxysmal or persistent AF were treated at two centres. Patients were analysed in five cohorts based upon ablation settings, catheter, and mapping system. Pulsed field ablation was performed in 82 patients (74% male, 42 paroxysmal AF). Pulmonary vein isolation was achieved in 100% of pulmonary veins (322/322) with first-pass isolation in 92.2% (297/322). There were four serious adverse events of interest (three vascular access complications and one lacunar stroke). Eighty patients (98%) underwent invasive remapping. Pulsed field ablation development Cohorts 1 and 2 showed a per-patient isolation rate of 38% and 26% and a per-PV isolation rate of 47% and 53%, respectively. Optimized PFA Cohorts 3-5 showed a per-patient isolation rate of 60%, 73%, and 81% and a per-PV isolation rate of 84%, 90%, and 92%, respectively.

CONCLUSION

ECLIPSE AF demonstrated that optimized PFA using the CENTAURI System with three commercial, contact force-sensing, solid-tip focal ablation catheters resulted in transmural lesion formation and high proportion of durable PVI with a favourable safety profile, thus providing a viable treatment option for AF that integrates with contemporary focal ablation workflows.

Incidence of ablation-induced esophageal lesions and gastroparesis in patients undergoing ablation index guided high power short duration atrial fibrillation ablation

INTRODUCTION

Aim of this study was to evaluate the incidence of ablation-induced endoscopically detected esophageal lesions (EDEL) and gastroparesis in patients undergoing high-power short-duration (HPSD) atrial fibrillation (AF) ablation using different target ablation index (AI) values.

METHODS AND RESULTS

Consecutive patients undergoing AF ablation were included. Radiofrequency (RF) ablation was performed using HPSD ablation (50 W, target AI of 320 and 350 (group 1) and 380 (group 2) at posterior wall). Postablation endoscopy was performed in all patients. In total, 233 patients (66.8 ± 10 years; 52% male) were included consecutively (n = 137 patients in group 1 and n = 96 patients in group 2). Mean AI values und RF time at posterior wall was significantly higher and longer in group 2 compared to group 1 patients (413 ± 9 vs. 392 ± 19 AI, p < 0.01; 9.0 ± 0.8 s vs. 7.8 ± 0.7 s, p < 0.01). Esophageal endoscopy revealed esophageal lesions or gastroparesis in 43 of 233 patients (18.5%) in the total cohort (13.1% in group 1 and 26.0% in group 2; p = 0.02). Incidence of EDEL was 8.0% and 13.5% in group 1 and group 2, respectively. According to logistic analysis incidence of EDEL and/or gastroparesis was significantly lower in patients with a higher body mass index and higher in group 2 patients compared to group 1 patients.

CONCLUSION

The incidence of EDEL or gastroparesis in patients undergoing HPSD AF ablation was 18.5% in the total cohort. The risk of EDEL and gastroparesis was associated with a higher AI target value of 380 compared to 320 and 350 at posterior wall and was reversely associated with body mass index.

Oesophageal safety in voltage-guided atrial fibrillation ablation using ablation index or contact force only: a prospective comparison

AIMS

Left atrial ablation using radiofrequency (RF) is associated with endoscopically detected thermal oesophageal lesions (EDELs). The aim of this study was to compare EDEL occurrence after conventional contact force-guided (CFG) RF ablation vs. an ablation index-guided (AIG) approach in clinical routine of voltage-guided ablation (VGA). Predictors of EDEL were also assessed.

METHODS AND RESULTS

This study compared CFG (n = 100) with AIG (n = 100) in consecutive atrial fibrillation ablation procedures, in which both pulmonary vein isolation and VGA were performed. In the AIG group, AI targets were ≥500 anteriorly and ≥350-400 posteriorly. Upper endoscopy was performed after ablation.The CFG and AIG groups had comparable baseline characteristics. The EDEL occurred in 6 and 5% (P = 0.86) in the CFG and AIG groups, respectively. Category 2 lesions occurred in 4 and 2% (P = 0.68), respectively. All EDEL healed under proton pump inhibitor therapy. The AI > 520 was the only predictor of EDEL [odds ratio (OR) 3.84; P = 0.039]. The more extensive Category 2 lesions were predicted by: AI max > 520 during posterior ablation (OR 7.05; P = 0.042), application of posterior or roof lines (OR 5.19; P = 0.039), existence of cardiomyopathy (OR 4.93; P = 0.047), and CHA2DS2-VASc score (OR 1.71; P = 0.044). The only Category 2 lesion with AI max < 520 (467) occurred in a patient with low body mass index.

CONCLUSIONS

Both methods were comparable with respect to clinical complications and EDEL. In consideration of previous reconnection data and our study results regarding oesophageal safety, optimal AI target range might be between 400 and 450.

Esophageal Protection and Temperature Monitoring Using the Circa S-Cath™ Temperature Probe during Epicardial Radiofrequency Ablation of the Pulmonary Veins and Posterior Left Atrium

Although epicardial bipolar radiofrequency ablation should diminish the risk of esophageal thermal injury in comparison to an endocardial ablation, cases of lethal atrio-esophageal fistula have been reported. To better understand this risk and to reduce the possibility of a thermal injury, we monitored the esophageal temperature with the Circa S-Cath™ temperature probe during and immediately after the ablation while implementing three procedural safety measures. Twenty patients (15 males; 63 ± 10 years) were prospectively enrolled (November 2019-February 2021). All patients underwent an epicardial ablation procedure, including an antral left and right pulmonary vein isolation with bidirectional bipolar clamping, and a roof and inferior line using unidirectional bipolar radiofrequency. Three procedural preventive mitigations were implemented: (1) transesophageal echocardiographic visualization of the atrio-esophageal interface, with probe retraction before the energy delivery; (2) lifting the ablated tissue away from the esophagus during an energy application; and (3) a 30 s cool-off and irrigation period after the energy delivery. The esophageal temperature was recorded using an insulated multisensory intraluminal esophageal temperature probe (Circa S-Cath™). Of the 20 patients enrolled, 7 patients had paroxysmal atrial fibrillation (AF), 8 persistent AF and 5 longstanding persistent AF. The average maximum luminal esophageal temperature observed was 36.2 ± 0.7 °C (34.8-38.2 °C). In our clinical experience, no abrupt increase in the luminal esophageal temperature above the baseline was observed. Since no measurements exceeded the threshold of 39 °C, no prompt interruption of energy delivery was required. Intraluminal esophageal temperature monitoring is feasible and can be helpful in confirming correct catheter position and safe energy application in bipolar epicardial left atrial ablation. Intra-procedural preventive mitigations should be implemented to reduce the risk of esophageal temperature rises.

Radiofrequency Pulmonary Vein Isolation without Esophageal Temperature Monitoring: Contact-Force Characteristics and Incidence of Esophageal Thermal Damage

Esophageal thermal lesions following pulmonary vein isolation (PVI) for atrial fibrillation (AF) potentially harbor lethal complications. Radiofrequency (RF)-PVI using contact force-technology can reduce collateral damage. We evaluated the incidence of endoscopically detected esophageal lesions (EDEL) and the contribution of contact force to esophageal lesion formation without esophageal temperature monitoring. One hundred and thirty-one AF patients underwent contact force-guided RF-PVI. Contact force, energy, force-time-integral, and force-power-time-integral were adopted. During PVI at the posterior segment of the wide antral circumferential line, limits were set for energy (30 W), duration (30 s) and contact force (40 g). Ablations were analyzed postero-superior and -inferior around PVs. Endoscopy within 120 h identified EDEL in six patients (4.6%). In EDEL(+), obesity was less frequent (17% vs. 68%, p = 0.018), creatinine was higher (1.55 ± 1.18 vs. 1.07 ± 0.42 mg/dL, p = 0.016), and exclusively at the left postero-inferior site, force-time-integral and force-power-time-integral were greater (2973 ± 3267 vs. 1757 ± 1262 g·s, p = 0.042 and 83,547 ± 105,940 vs. 43,556 ± 35,255 g·J, p = 0.022, respectively) as compared to EDEL(-) patients. No major complications occurred. At 12 months, arrhythmia-free survival was 74%. The incidence of EDEL was low after contact force-guided RF-PVI. Implementing combined contact force-indices on the postero-inferior site of left-sided PVs may reduce EDEL.

Efficacy of ablation index-guided pulmonary vein isolation in patients with paroxysmal atrial fibrillation

BACKGROUND

Ablation index (AI) is a novel technology of ablation lesion quality to help improve homogeneity of lesion size and continuity. In this study, we aim to evaluate whether AI-guided PVI improves clinical outcomes compared to CF-guided PVI in patients with paroxysmal AF (PAF).

METHODS

Patients undergoing first-time radiofrequency ablation for PAF were randomized in a 2:1 ratio to two groups: AI-guided PVI and CF-guided PVI. In the AI group, AI ≥500 was recommended at the anterior/superior/inferior walls, 350-400 at the posterior wall, and inter-lesion distance ≤4 mm. The primary endpoint is the freedom from atrial arrhythmia recurrence during 12 months follow-up, without antiarrhythmic drug therapy (ADT). The key secondary endpoints include intra-procedural efficiency and peri-procedural complications.

RESULTS

225 patients were randomized (AI group (n = 149) and CF group(n = 76)). First-pass isolation rate in AI group was significantly higher than that in CF group (58.3% vs. 43.4%, p = 0.035). After a median follow-up of 12.2 months, 154/225(68.4%) of patients were free from atrial arrhythmia recurrence without ADT, which was higher in AI group compared with CF group, but without significant difference (71.1% vs. 63.2%, p = 0.253). The incidence of peri-procedural complications is low and without difference between two groups.

CONCLUSIONS

AI-guided ablation provided higher acute efficacy than CF-guided ablation in PV isolation for patients with paroxysmal AF. The long-term success rate in AI group was higher than CF group, but did not reach statistical significance. This article is protected by copyright. All rights reserved.

Ablation index-guided ablation with milder targets for atrial fibrillation: Comparison between high power and low power ablation

Background

High power-ablation index (HP-AI)-guided ablation for atrial fibrillation (AF) targeting high AIs has been implemented in European countries. However, milder AI targets are widely used in Asia. The safety and efficacy of HP-AI-guided ablation compared with those of low-power AI-guided ablation in a milder AI-targeting setting are unknown. The goal of this study was to explore the efficacy and safety of HP-AI-guided ablation in a milder AI-targeting setting.

Methods

Patients who underwent pulmonary vein isolation (PVI) for AI-guided atrial fibrillation ablation in our center were enrolled and divided into 2 groups according to the ablation power used. In the HP-AI group, the ablation power was over 45 W, while the low power-AI group was ablated with <35 W power. The targeted AIs were 450–500 in the anterior wall and 350–400 in the posterior wall. The efficacy outcome was expressed as the single-procedure atrial arrhythmia-free survival between 91 days and 1 year. Safety outcomes included severe adverse events (SAEs), including symptomatic pulmonary vein (PV) stenosis, atrioesophagal fistula, cardiac tamponade, stroke, thromboembolism events, myocardial infarction, and major bleeding.

Results

A total of 134 patients were enrolled, of whom 74 underwent PVI using HP-AI, while 60 received low power-AI ablation. After a mean follow-up time of 7.4 months, 22 (16.4%) patients showed arrhythmia recurrence: 5 (6.8%) patients in the HP-AI group and 17 (28.3%) patients in the low power-AI group. The HP-AI group showed a significantly higher arrhythmia-free survival than the low power-AI group (p = 0.011). Two patients in the low power-AI group and 1 patient in the HP-AI group developed an SAE (p = NS). Compared with the low power-AI group, the HP-AI group demonstrated a higher PV first-pass isolation rate, shorter ablation time, and fewer patients with anatomical leakages and sites of unreached AI.

Conclusion

In a milder AI setting, HP-AI ablation might result in significantly higher arrhythmia-free survival than low power-AI ablation and a similar safety profile.

Acute oesophageal safety of high-power short duration with 50 W for atrial fibrillation ablation

Aims

Pulmonary vein isolation (PVI) using radiofrequency (RF) ablation is an effective treatment option for patients with atrial fibrillation (AF). This study aims to investigate the safety of high-power short duration (HPSD) with emphasis on oesophageal lesions after PVI.

Methods and results

Consecutive patients undergoing AF ablation with HPSD (50 W; ablation index (AI)-guided; target AI 350 for posterior wall ablation, AI 450 for anterior wall ablation) using the ThermoCool SmartTouch SF catheter were included. Patients underwent post-ablation oesophageal endoscopy to detect and categorize thermal oesophageal injury (EDEL). Occurrence and risk factors of oesophageal lesions and perforating complications were analysed. A total of 1033 patients underwent AF ablation with HPSD. Of them, 953 patients (67.6 ± 9.6 years; 58% male; 43% paroxysmal AF; 68% first PVI) underwent post-procedural oesophageal endoscopy and were included in further analyses. Median procedure time was 82.8 ± 24.4 min with ablation times of 16.1 ± 9.2 min. Thermal oesophageal injury was detected in 58 patients (6%) (n = 29 Category 1 erosion, n = 29 Category 2 ulcerous). One patient developed oesophageal perforation (redo, 4th AF ablation). No patient died. Using multivariable regression models, increased total ablation time [odds ratio (OR) 1.029, P = 0.010] and history of stroke (OR 2.619, P = 0.033) were associated with increased incidence of EDEL after AF ablation, whereas increased body mass index was protective (OR 0.980, P = 0.022).

Conclusion

Thermal oesophageal lesions occur in 6% of HPSD AF ablations. The risk for development of perforating complications seems to be low. Incidence of atrio-oesophageal fistula (0.1%) is comparable to other reported series about RF ablation approaches.

Adverse events related to AtriCure EPi-Sense Coagulation Device-Analysis of the FDA MAUDE database

INTRODUCTION

The AtriCure EPi-Sense Device is used for the hybrid convergent procedure, an emerging treatment for persistent atrial fibrillation (AF) and long-standing persistent AF. However, data on the AE related to the EPi-Sense device are scarce.

METHODS

Keyword "EPI-SENSE" was searched on the MAUDE database. There were 80 device reports from 2016 to 2020. After excluding reports when the device was not returned for evaluation, 79 device reports were included for final analysis.

RESULTS

The adverse events (AE) were broadly classified into 11 categories. The most common complications were pericardial effusion (25.3%), stroke (17.7%), and atrioesophageal fistula (AEF) (8.9%). Death was reported in 15 (19%) cases, 3 of which were due to pulmonary embolism, 6 due to AEF, 3 due to unknown cause, 1 due to sepsis, 2 due to events related to acute renal failure.

DISCUSSION

Pericardial effusion is a common AE reported in patients with convergence procedures and is well documented in the CONVERGE trial. The convergent procedure is unique in that the epicardial ablations are performed on the posterior wall with the radiofrequency probe directed towards the heart and away from the esophagus which in theory should reduce esophageal injuries. Despite that, a high number of AEF were noticed. Finally, there were also some reports of saline perfusion malfunction which can lead to injuries due to overheating.

CONCLUSION

This analysis of the AE related to the EPi-Sense device highlights several major AE that are previously unreported.

Esophageal temperature during atrial fibrillation ablation poorly predicts esophageal injury: An observational study

Background

Esophageal injury (EI) remains a concern when performing pulmonary vein isolation (PVI) using the high-power short-duration (HPSD) technique.

Objective

We aim to indicate that high esophageal temperature during HPSD PVI does not correlate with positive esophageal endoscopy (EGD) findings.

Methods

A retrospective observational study was performed on 43 patients undergoing PVI using HPSD (50 W for 6–7 seconds per lesion) at Tulane Medical Center from July 2020 to January 2021. Esophageal temperature was monitored throughout the procedure using a temperature probe and patients underwent EGD the following day. Small ulcers, nonbleeding erosions, erythema, and/or esophagitis were considered positive EGD findings.

Results

Mean age was 64.9 years; 46.5% of the patients were female. Eleven patients had positive EGD findings (group 1) and 32 patients had normal EGD (group 2). There was no statistical difference in mean esophageal peak temperature between group 1 and group 2 (43.9°C ± 2.9°C and 42.5°C ± 2.3°C, respectively, P = .17). There was no association between positive EGD results and esophageal temperature during PVI. Mean baseline esophageal temperature was similar in both groups (36.1°C, P = .78). Average contact force (P = .53), ablation time (P = .67), age (P = .3096), sex (P = .4), body mass index (P = .14), and other comorbidities did not correlate with positive endoscopy results. We found positive correlation between the distance of the left atrium (LA) to esophagus and positive EGD (P = .0001).

Conclusion

EI during HPSD PVI does not correlate to esophageal temperature changes during ablation. However, esophageal injury does correlate to a shorter proximity of the esophagus to the LA.

Impact of Active Esophageal Cooling on Fluoroscopy Usage During Left Atrial Ablation

Risks to collateral structures exist with radiofrequency (RF) ablation of the left atrium to obtain pulmonary vein isolation (PVI) for the treatment of atrial fibrillation. Passive luminal esophageal temperature (LET) monitoring is commonly utilized, but increasing data suggest limited benefits with LET monitoring. In contrast, active cooling of the esophagus has been shown to significantly reduce esophageal injury. Active cooling of the esophagus also avoids the need for stopping and repositioning an LET probe during use, which may reduce the need for fluoroscopy use. This study aimed to measure the impact on fluoroscopy use during RF ablation with esophageal cooling using a dedicated cooling device in a low-fluoroscopy practice. All patients who underwent PVI over a one-year timeframe by a single provider were analyzed. Patients undergoing PVI prior to the incorporation of an esophageal cooling protocol into standard ablation practice were treated with traditional LET monitoring. Patients treated after this point received active esophageal cooling, in which no LET monitoring is utilized. A total of 280 patients were treated; 91 patients were treated using LET monitoring, and 189 patients were treated with esophageal cooling. The mean total fluoroscopy time before the implementation of the esophageal cooling protocol in 91 patients was 194 seconds [standard deviation (SD): 182 seconds] per case, with a median of 144 seconds. The mean total fluoroscopy time after implementation in 189 patients was 126 seconds (SD: 120 seconds) per case with a median of 96 seconds, representing a reduction of 35% per case (p < 0.0001, Mann-Whitney U test). In this largest study to date of active esophageal cooling during PVI, a 35% reduction in fluoroscopy time compared with patients who received LET monitoring was found. This reduction was seen despite an already low fluoroscopy usage rate in place.

Catheter ablation of atrial fibrillation using ablation index-guided high-power technique: Frankfurt AI high-power 15-month follow-up

BACKGROUND

Radiofrequency (RF) high-power ablation appears to be a novel concept in treating atrial fibrillation (AF). The ablation-index (AI) has been linked with the durability of pulmonary vein isolation (PVI). To report the midterm clinical results of a new ablation strategy using AI-guided high-power (50 W) ablation (AI-HP).

METHODS AND RESULTS

Symptomatic AF patients were included and underwent wide-area circumferential PVI. Contact-force catheters were used, RF power was set to 50 W targeting AI values (550/400 for anterior/posterior) and interlesion distance 6 mm. Luminal esophageal temperature (LET) was monitored during the procedure; patients with LET ≥39°C underwent post-ablation esophageal-endoscopy. Seventy-two-hour-Holter ECGs were scheduled during follow-up. Procedural PVI was achieved in all (N = 122; mean age, 68.2 years; male, 71.3%) patients, rate of first-pass PVI was 96.7% per patient. Procedural mean RF time was 11.5 min, and mean RF time during posterior wall segment was 3.1 min. Per RF-lesion, the mean contact force, RF duration, AI, and impedance-drop at anterior/posterior wall were 26 ± 14 g/23 ± 12 g, 16.2 ± 7.5 s/8.8 ± 3.6 s, 552 ± 53/438 ± 47, and 13 ± 6 Ω/9 ± 5 Ω, respectively. Mean PVI procedural-time, 55.8 min; mean procedural fluoroscopic time, 5.6 min. Three (2.5%) patients had asymptomatic endoscopic small erosion/erythema esophageal lesions, no serious adverse events were observed. During a 15-month follow-up, overall single-procedure freedom from clinical recurrence of AF/atrial tachycardia (AT) off antiarrhythmic drug after blanking period was 85.2% (89.4% for paroxysmal AF, 80.4% for persistent AF).

CONCLUSION

The AI-HP (50 W) appears as an efficient ablation technique in treating AF and leads to a high single-procedure arrhythmia-free survival at 15 months.

Esophageal Thermal Injury after Catheter Ablation for Atrial Fibrillation with High-Power (50 Watts) Radiofrequency Energy

Background and Objectives

Data regarding the safety of atrial fibrillation (AF) ablation using high-power (50 W) radiofrequency (RF) energy in Asian populations are limited. This study was conducted to evaluate the incidence and pattern of esophageal injury after high-power AF ablation in an Asian cohort.

Methods

We searched the prospective AF ablation registry to identify patients who underwent AF ablation with 50 W RF energy using the smart touch surround flow catheter (Biosense Webster, Diamond Bar, CA, USA). Visitag™ (Biosense Webster) was used for lesion annotation with predefined settings of catheter stability (3 mm for 5 seconds) and minimum contact force (50% of time >5 g). All patients underwent upper gastrointestinal endoscopy at 1 or 3 days after the ablation.

Results

A total of 159 patients (mean age: 63±9 years, male: 69%, paroxysmal AF: 45.3%, persistent AF: 27.7%, long-standing persistent AF: 27.0%) were analyzed. Initially, 26 patients underwent pulmonary vein isolation with 50 W for 5 seconds at each point. The remaining 133 patients underwent prolonged RF duration (anterior 10 seconds and posterior 6 seconds). The incidence rates of esophageal erythema/erosion and superficial ulceration were 1.3% for each type of the lesion. Food stasis, a suggestive finding of gastroparesis, was observed in 25 (15.7%) patients. There were no cases of cardiac tamponade, stroke, or death.

Conclusions

In Asian patients, AF ablations using 50 W resulted in very low rates of mild esophageal complications.

Incidence of Esophageal Thermal Injury Using a Safety Protocol During Atrial Fibrillation Ablation

Objective: Catheter ablation has been a common procedure used for the management of atrial fibrillation (AF). Atrioesophagel fistula (AEF) is one of the most feared complications of AF ablation. Although it is a rare complication, severe esophageal thermal injury must be avoided. It is important to describe a safe method of preventing esophageal injuries without increasing AF recurrence. Methods: A retrospective cohort study of consecutive patients who underwent radiofrequency AF catheter ablation during 1 year-period wa conducted. One hundred and four patients were enrolled divided in two groups: one with a maximum recorded esophageal temperature (ET) < 38 °C and other with a maximum recorded ET ≥ 38 °C. The primary endpoint was detection of endoscopic esophageal lesions after AF ablation and the secondary endpoint was AF recurrence according to the maximum ET reached during the procedure. Results: The maximum ET was on average 37.3 ± 1.0 °C. Only 4 (3.8%) patients had esophageal lesion diagnosed by upper gastrointestinal endoscopy. There were no cases of esophageal perforation. The AF recurrence rate was 9.6% during the follow-up (10 patients, 3 from the ET max < 38 °C group and 7 from the ET max ≥ 38 °C group; p = 0.181). The maximum ET was not associated with AF recurrence after catheter ablation (OR = 1.65, 95% CI = 0.84-3.24, p = 0.14). Conclusions: A low incidence of esophageal injury after AF ablation with the use of a specific esophageal protection protocol was found. There was no esophageal perforation. The AF recurrence rate was similar to that described in the literature.

Atrioesophageal fistula post atrial fibrillation ablation: A multicenter study from China

BACKGROUND AND OBJECTIVE

Atrioesophageal fistula (AEF) is a rare but devastating complication with high mortality post atrial fibrillation (AF) ablation. The purpose of current study was to determine the epidemiology, clinical features, pathogenesis, and management of AEF after AF ablation.

METHODS AND RESULTS

Patients with diagnosed AEF were included and retrospectively analyzed according to the registry of 11 centers in China from January 2010 to December 2019. A total of 16 AEF cases were identified from 44 794 patients who received a left atrial ablation procedure (0.035% per procedure). The interval from procedure to clinical onset of AEF averaged 18.3 days (3-39 days). The fever ranked the most common symptom, occurred in 14 of the 16 cases, followed by neurological deficits (n = 11), chest pain (n = 5), and hematemesis (n = 4). Patients undergoing surgical repair had a better prognosis compared to those receiving nonsurgical management ([4 of 8] 50.0% vs [8 of 8] 100%, P < .05) with an overall mortality rate of 75.0%.

CONCLUSION

AEF is highly characterized by varied manifestations. Early diagnosis and urgent surgical repair are vital to those patients and associated with improved survival rates.

Current Status of Esophageal Protection

Catheter ablation of atrial fibrillation necessitates ablation on the posterior left atrium. The anterior esophagus touches the posterior left atrium, although its course is highly variable. The proximity of the left atrium to the esophagus confers risk of injury with radiofrequency and cryoablation owing to the heat transfer that occurs with thermal ablation. Early detection of esophageal temperature changes with probes may decrease the extent of damage to the esophagus, but evidence is mixed. Avoiding ablation on the esophagus with esophageal deviation and modifying ablation approaches may decrease the risk of injury.

Risk of esophageal thermal injury during catheter ablation for atrial fibrillation guided by different ablation index

BACKGROUND

During ablation for atrial fibrillation (AF), energy delivery toward the left atrial posterior wall may cause esophageal injury (EI). Ablation index (AI) was introduced to estimate ablation lesion size, however, the impact of AI technology on the risk of EI has not been explored.

METHOD

From March 2019 to December 2019, 60 patients with paroxysmal AF undergoing first-time ablation were prospectively enrolled. The first 30 consecutive patients were ablated with the AI target value of 400 (AI-400 group), and the later 30 consecutive patients were ablated with the AI target value of 350 at the posterior wall (AI-350 group). Endoscopic ultrasonography was used to evaluate EI postablation. EI was classified as a category 1 (erythema or erosion) or a category 2 (hematoma or ulceration).

RESULTS

Compared with the AI-400 group (59.9 ± 8.4 years; male, 60%), the AI-350 group (59.1 ± 9.9 years; male, 50%) had a lower incidence of EI (3.3% vs 26.7%, P = .03). There was no significant difference in the percentage of first-pass PVI between the AI-400 group and the AI-350 group (left PVI: 80% vs 73.4%, P = .54; right PVI: 80% vs 60%, P = .1). Neither ablation time nor fluoroscopy time was significantly different between the AI-400 group and the AI-350 group.

CONCLUSIONS

AF ablation guide by AI target value of 350 may reduce esophageal thermal injury and has a similar efficiency on the acute success rate of first-pass PVI compared with an AI target value of 400 at the posterior wall.

Management of Atrio-esophageal Fistula Induced by Radiofrequency Catheter Ablation in Atrial Fibrillation Patients: a Case Series

Atrio-esophageal fistula (AEF) is one of the most devastating complication of radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) and surgical repair is strongly recommended. However, optimal surgical approach remains to be elucidated. We retrospectively reviewed AEF cases that occurred after RFCA in a single center and evaluated the clinical results of different surgical approach. Surgical or endoscopic repair was attempted in five AF patients who underwent RFCA. Atrio-esophageal fistula and mediastinal infection was not controlled in the patient who underwent endoscopic repair eventually died. Lethal cerebral air embolism occurred two days after surgery in a patient who underwent esophageal repair only. Primary surgical repair of both the left atrium (LA) and esophagus was performed in the remaining three patients. Among these three patients, two underwent external LA repair and the remaining had internal LA repair via open-heart surgery. External repair of the LA was unsuccessful and one patient dies and another had to undergo second operation with internal repair of the LA. The patient who underwent internal LA repair during the first operation survived without additional surgery. Furthermore, we applied veno-arterial extracorporeal membrane oxygenation (VA-ECMO) with artificial induction of ventricular fibrillation in this patient to prevent air and septic embolism and she had no neurologic sequelae. In summary, surgical correction can be considered preferentially to correct AEF. Open-heart surgical repair of LA from the internal side seems to be an acceptable surgical method. Application of VA-ECMO with artificial induction of ventricular fibrillation might be effective to prevent air and septic embolism.