Esophageal Deviation Research Articles

Predictive Value of Esophageal Deviation Index for Clinical Outcomes of Patients With Left-Sided Congenital Diaphragmatic Hernia

PurposeThis study aimed to evaluate the prognostic value of postnatal esophageal deviation index (EDI) measured within the first 24 h of life for predicting mortality and morbidity in neonates with left-sided congenital diaphragmatic hernia (L-CDH). MethodThis retrospective study analyzed clinical data from 133 neonates with L-CDH admitted to Guangzhou Women and Children's Medical Center between January 2016 and January 2024. Patients were categorized into two groups based on outcomes: survivors (n = 108) and non-survivors (n = 27). Risk factors for mortality were identified using both univariate and multivariate analyses. A receiver operating characteristic (ROC) curve was utilized to evaluate the predictive value of EDI for mortality in L-CDH patients. Subsequently, patients were divided into two groups: those with an EDI> 16.1% and those with an EDI≤16.1%. The relationship between EDI and both mortality and morbidity was analyzed using Kaplan–Meier analysis, chi-square test, Fisher's exact test, and multivariate analysis. ResultsEDI (adjusted OR: 0.822, 95% CI 0.723–0.935; P = 0.003) was identified as the independent predictor of mortality through both univariate and multivariate logistic regression analysis. The ROC curve demonstrated that the area under the curve (AUC) for predicting the mortality was 0.854 (95%CI: 0.782–0.930) for EDI, with an optimal cut-off value of 16.125%. The cumulative mortality rate through Day 200 was higher in patients with an EDI>16.1% (P＜0.001). Among the 133 neonates with L-CDH, 24.8% had an EDI>16.1%. This was associated with significantly worse CDH characteristics, including a high incidence of intrathoracic stomach and a high occurrence of high-risk defect sizes (type C/D), (P＜0.001), as well as more severe pulmonary hypertension (P＜0.001). An EDI>16.1% was associated with higher mortality and a greater need for ECMO support compared to an EDI≤16.1% (P＜0.001). ConclusionEDI within the first 24 h of life in patients with L-CDH is associated with increased mortality and the need for ECMO, particularly when EDI exceeds 16.1%. Level of EvidenceIII.

Posterior Tracheopexy for Tracheomalacia: A Study of Clinical and Radiological Consequences on Esophagus.

Posterior tracheopexy (PT) directly addresses the posterior trachealis membrane intrusion in severe tracheomalacia. During PT, the esophagus is mobilized and membranous trachea is sutured to the prevertebral fascia. Although dysphagia has been reported as a possible complication of PT, in the literature there are no data investigating postoperative esophageal anatomy and digestive symptoms. Our aim was to study clinical and radiological consequences of PT on esophagus. Patients with symptomatic tracheobronchomalacia scheduled for PT between May 2019 and November 2022 underwent pre- and postoperative esophagogram. For each patient, we analyzed radiological images and measured esophageal deviation providing new radiological parameters. All 12 patients underwent thoracoscopic PT (n = 3) or robot-assisted thoracoscopic PT (n = 9). For all patients, the postoperative esophagogram showed a right dislocation of the thoracic esophagus (median postoperative deviation = 27.5 mm). We report an esophageal perforation at postoperative day 7 in a patient affected by esophageal atresia, who underwent several surgical procedures before. A stent was placed and esophagus healed. Another patient with severe right dislocation referred transient dysphagia to solids, which resolved gradually in the first postoperative year. All the other patients did not present any esophageal symptoms. For the first time, we demonstrate the right dislocation of the esophagus after PT and we propose an objective method to measure it. In most patients, PT is a procedure not affecting esophageal function, but dysphagia can occur if dislocation is important. Esophagus mobilization during PT should be cautious, especially in patients who underwent previous thoracic procedures.

Association between proactive esophageal cooling and increased lab throughput.

Proactive esophageal cooling has been FDA cleared to reduce the likelihood of ablation-related esophageal injury resulting from radiofrequency (RF) cardiac ablation procedures. Data suggest that procedure times for RF pulmonary vein isolation (PVI) also decrease when proactive esophageal cooling is employed instead of luminal esophageal temperature (LET) monitoring. Reduced procedure times may allow increased electrophysiology (EP) lab throughput. We aimed to quantify the change in EP lab throughput of PVI cases after the introduction of proactive esophageal cooling. EP lab throughput data were obtained from threeEPgroups. We then compared EP lab throughput over equal time frames at each site before (pre-adoption) and after (post-adoption) the adoption of proactive esophageal cooling. Over the time frame of the study, a total of 2498 PVIs were performed over a combined 74 months, with cooling adopted in September 2021, November 2021, and March 2022 at each respective site. In the pre-adoption time frame, 1026 PVIs were performed using a combination of LET monitoring with the addition of esophageal deviation when deemed necessary by the operator. In the post-adoption time frame, 1472 PVIs were performed using exclusively proactive esophageal cooling, representing a mean 43% increase in throughput (p < .0001), despite the loss of two operators during the post-adoption time frame. Adoption of proactive esophageal cooling during PVI ablation procedures is associated with a significant increase in EP lab throughput, even after a reduction in total number of operating physicians in the post-adoption group.

Esophageal injury, perforation, and fistula formation following atrial fibrillation ablation.

Esophageal perforation and fistula formation are rare but serious complications following atrial fibrillation ablation. In this review article, we outline the incidence, pathophysiology, predictors, and preventative strategies of this dreaded complication. We conducted an electronic search in 10 databases/electronic search engines to access relevant publications. All articles reporting complications following atrial fibrillation ablation, including esophageal injury and fistula formation, were included for systematic review. A total of 130 manuscripts were identified for the final review process. The overall incidence of esophageal injury following atrial fibrillation ablation was significantly higher with thermal ablation modalities (radiofrequency 5-40%, cryoballoon 3-25%, high-intensity focused ultrasound < 10%) as opposed to non-thermal ablation modalities (no cases reported to date). The incidence of esophageal perforation and fistula formation with the use of thermal ablation modalities is estimated to occur in less than 0.25% of all atrial fibrillation ablation procedures. The use of luminal esophageal temperature monitoring probe and mechanical esophageal deviation showed protective effect toward reducing the incidence of this complication. The prognosis is very poor for patients who develop atrioesophageal fistula, and the condition is rapidly fatal without surgical intervention. Esophageal perforation and fistula formation following atrial fibrillation ablation are rare complications with poor prognosis. Various strategies have been proposed to protect the esophagus and reduce the incidence of this fearful complication. Pulsed field ablation is a promising new ablation technology that may be the future answer toward reducing the incidence of esophageal complications.

Safety of an esophageal deviator for atrial fibrillation catheter ablation.

Esophageal thermal injury is a complication of atrial fibrillation (AF) ablation, and it can be avoided by esophageal deviation during left atrial posterior wall radiofrequency catheter ablation. This study aimed to evaluate the safety of a nitinol-based mechanical esophageal displacement device (MEDD) and its performance. This preclinical safety study was conducted on 20 pigs, with 10 undergoing radiofrequency AF ablation using the MEDD and 10 serving as a control group under anticoagulation but without radiofrequency application. Esophageal traumatic injuries were classified from 0 to 4 and were grouped as absent (grade 0), minor (grade 1 or 2), moderate (grade 3), or major risk lesions (grade 4) by anatomopathological study. Grades 1 and 2 were considered acceptable. Fluoroscopy was used to measure displacement. Five (25%) pigs developed traumatic lesions, 4 with grade 1 and 1 with grade 2 (2-mm superficial ulcer). There was no difference in lesion occurrence between the radiofrequency and control groups (30% and 20%, respectively; P = .43). Under rightward displacement, the right edge moved 23.9 (interquartile range [IQR] 21.3-26.3) mm and the left edge moved 16.3 (IQR 13.8-18.4) mm (P < .001) from baseline. Under leftward displacement, the right edge moved 13.5 (IQR 10.9-15.3) mm and the left edge moved 16.5 (IQR 12.3-18.5) mm (P = .07). A perforation to the pharyngeal diverticulum occurred in 1 pig, related to an accidental extubation. In pigs, the MEDD demonstrated safety in relation to esophageal tissue, and successful deviation. Esophageal traumatic injuries were acceptable, but improper manipulation led to pharyngeal lesion.

A novel esophageal retractor with eccentric balloon during atrial fibrillation ablation.

Due to the anatomically adjacent relationship between the left atrium (LA) and esophagus, energy delivery on the posterior wall of LA is limited. The aim of this study was to evaluate the feasibility of a novel esophageal retractor (SAFER) with an inflatable C-curve balloon during atrial fibrillation (AF) ablation. Nine patients underwent AF ablation assisted with the SAFER. After inflation, the esophagus was deviated laterally away from the intended ablation site of the posterior wall under local anesthesia. The extent of mechanical esophageal deviation (MED) was evaluated under fluoroscopy, defined as the shortest distance from the trailing esophageal edge to the closest point of the ablation line. Gastroscopy was performed before and after ablation. The target ablation index used in all LA sites including the posterior wall was 400-450 after effective MED. All adverse events during the periprocedural period were recorded. The mean deviation distance achieved 16.2±9.6mm away from the closest ablation point of the pulmonary vein lesion set. With respect to the individual left and right pulmonary vein lesion sets, the deviation distance was 19.7±11.5 and 12.7±6.8mm, respectively. The extent of deviation was 0 to 5mm, 5.1 to 10mm, or>10mm in 0(0%), 7(38.9%), and 11(61.1%), respectively. Procedural success was achieved in all patients without acute reconnection. There was only one esophageal complication which manifested as esophageal erosion and this patient experienced throat pain possibly related to the SAFER retractor with no clinical sequelae. Esophageal deviation with the novel eccentric balloon is a novel feasible choice during AF ablation, enabling adequate energy delivery to the posterior wall of LA. Additional prospective randomized controlled studies are required for further validation.

PO-02-074 A META-ANALYSIS TO EVALUATE THE EFFICACY OF ESOPHAGEAL COOLING IN PREVENTING ESOPHAGEAL INJURY DURING RADIOFREQUENCY ABLATION

Esophageal injury during radiofrequency (RF) ablation of atrial fibrillation (AF) is a known complication. It could range from mild esophagitis to esophageal ulcers. Atrio-esophageal fistula (AEF) is the most dreaded complication. It is rare but potentially life-threatening. Various measures to reduce esophageal injury including esophageal temperature monitoring, reducing ablation power on the posterior wall and esophageal deviation have been used. Esophageal cooling during RF ablation has been used as a strategy to reduce esophageal injury. We performed a meta-analysis evaluating the efficacy of esophageal cooling during RF ablation in reducing esophageal injury. We performed a systematic literature review in Embase, PubMed and SCOPUS for all the related articles until December 2022. The literature search yielded 28 publications, of which 6 studies fulfilled inclusion criteria. The Mantel- Haenszel random effects model was used to calculate odds ratio (OR) and 95% confidence intervals (CI). Outcomes analyzed were all esophageal lesions, mild to moderate and severe esophageal lesions as determined by post-procedure endoscopy. Esophageal cooling was performed in 469 patient and no esophageal cooling was used in 195 patients. Esophageal cooling significantly reduced severe esophageal injuries (OR = 0.37, 95% CI [0.18-0.79], P=0.01). There was no significant difference between the treatment groups in total number of esophageal lesion (OR = 0.60, 95% CI [0.22-1.64], P=0.32) and mild to moderate lesions (OR = 1.48, 95% CI [0.48-4.51], P=0.49). Esophageal cooling during RF ablation in the left atrium reduces the incidence of severe esophageal lesions.

Postnatal Imaging for Prediction of Outcome in Patients with Left-sided Congenital Diaphragmatic Hernia

To evaluate associations between postnatal imaging features and outcome of left-sided congenital diaphragmatic hernia, as defined by overall survival and a requirement for extracorporeal membrane oxygenation (ECMO). Newborns diagnosed prenatally with left-sided congenital diaphragmatic hernia between January 2013 and September 2021 were studied retrospectively. The esophageal deviation index was newly defined as the largest diameter from the midline to deviated gastric tube divided by the largest transverse diameter of the thoracic cavity on the radiograph. Regression analyses were performed to identify postnatal imaging features associated with overall survival and a requirement for ECMO. The predictive power (ie, area under the curve [AUC] of a time-dependent receiver operating characteristic curve) of prenatal, postnatal, and intraoperative findings for predicting survival were calculated. Ninety-seven patients (54 males; mean gestational age, 38.3±1.9weeks; mean birth weight, 2956.5±540.0g) were analyzed. The esophageal deviation index (adjusted hazard ratio [HR], moderate [≥0.19 to <0.24], 6.427 [P=.029]; severe [≥0.24], 33.007 [P<.001]) and right pneumothorax (adjusted HR, 8.763; P=.002) were associated with overall survival and with a requirement for ECMO. Liver herniation on postnatal ultrasound also was associated with overall survival (P<.001) and need for ECMO (P=.001). In addition, the AUC for prediction of 1-year survival from postnatal ultrasound was comparable with that of prenatally or intraoperatively detected liver herniation (0.93; 95% CI, 0.88-0.97). The esophageal deviation index, right pneumothorax, and liver herniation observed by postnatal imaging have prognostic value in patients with left-sided congenital diaphragmatic hernia.

Innovations in atrial fibrillation ablation.

Catheter-based ablation to perform pulmonary vein isolation (PVI) has established itself as a mainstay in the rhythm control strategy of atrial fibrillation. This review article aims to provide an overview of recent advances in atrial fibrillation ablation technology. We reviewed the available literature and clinical trials of innovations in atrial fibrillation ablation technologies including ablation catheter designs, alternative energy sources, esophageal protection methods, electroanatomical mapping, and novel ablation targets. Innovative radiofrequency (RF) catheter designs maximize energy delivery while avoiding overheating associated with conventional catheters. Single-shot balloon catheters in the form of cryoballoons, radiofrequency, and laser balloons have proven effective at producing pulmonary vein isolation and improving procedural efficiency and reproducibility. Pulsed field ablation (PFA) is a highly anticipated novel nonthermal energy source under development, which demonstrates selective ablation of the myocardium, producing durable lesions while also minimizing collateral damage. Innovative devices for esophageal protection including esophageal deviation and cooling devices have been developed to reduce esophageal complications. Improved electroanatomical mapping systems are being developed to help identify additional non-pulmonary triggers, which may benefit from ablation, especially with persistent atrial fibrillation. Lastly, the vein of Marshall alcohol ablation has been recently studied as an adjunct therapy for improving outcomes with catheter ablation for persistent atrial fibrillation. Numerous advances have been made in the field of atrial fibrillation ablation in the past decade. While further long-term data is still needed for these novel technologies, they show potential to improve procedural efficacy and safety.

Recovery of conduction following high power short duration approach in radiofrequency catheter ablation for atrial fibrillation: a single-center experience

Abstract Introduction High-power short-duration (HPSD) ablation is currently being adopted by many as the preferred procedural technique in atrial fibrillation (AF). However, the optimal duration of energy delivery to successfully create a durable lesion is not clear yet. Purpose We evaluated the association of electrical reconnection with lesion-duration in HPSD ablation. Methods Consecutive AF patients undergoing repeat procedure after a prior HPSD ablation with or without isolation of left atrial appendage (LAA) and coronary sinus (CS) were included in this analysis. HPSD ablation was defined as ablation with maximum temperature setting at 420C and power delivery at 45 W for 10–15 sec (5 seconds in the CS area and posterior wall near the esophagus). In some patients a mechanical esophageal deviation tool was used to deflect the esophagus away from the ablation site. Results A total of 2249 AF patients (with LAA and CS isolation: 1451; without LAA and CS isolation: 798) receiving redo ablation after a prior HPSD procedure were included in the analysis. At the prior procedure with the HPSD approach, mean duration of ablation was significantly shorter in the area facing the esophagus compared to elsewhere (5.2±1.5 vs 12.5±1.7 seconds, p&amp;lt;0.001). Application duration was reduced to &amp;lt;10 sec to avoid overheating and steam pops in 1221 (84%) patients receiving LAA and CS isolation. At the redo, recovery of conduction was noted in the CS (592, 40.8%), LAA (493, 34%), and PV and left atrial posterior wall (LAPW) (310, 13.8%). Of the 310 patients with LAPW reconnection, 91% (n=282) had the conduction recovered in the area facing the esophagus. In 73 patients, esophageal displacement device was used during the prior HPSD ablation. Average duration of ablation lesions in LAPW among those 73 patients was 9.2±2 seconds. PV-LAPW reconnection was observed in 3/73 (4.1%) patients. Conclusion HPSD ablation with lesion duration of &amp;lt;10 sec was associated with conduction recovery in the LAA, CS and the LAPW area facing esophagus. Funding Acknowledgement Type of funding sources: None.

Cover Image, Volume 31, Issue 1

The back cover image is based on the Brief Communication Esophageal deviation with vacuum suction and mechanical deflection during ablation of atrial fibrillation: First in man evaluation by Luis Aguinaga et al., https://doi.org/10.1111/jce.14801.

Esophageal deviation with vacuum suction and mechanical deflection during ablation of atrial fibrillation: First in man evaluation.

Deviation of the esophagus during atrial fibrillation (AF) ablation can reduce esophageal injury. This study reports upon a novel esophageal retractor that utilizes vacuum suction and mechanical deflection to deviate the esophagus. The device was used in seven patients undergoing cryoballoon AF ablation. The esophagus was deviated 31.9 ± 4.4 mm to the right and 28.2 ± 5.9 mm to the left. Endoscopy at 4.4 ± 1.5 days postablation showed no esophageal injury. This study demonstrates the safe and effective deviation of the esophagus without a trailing edge with an esophageal retractor utilizing vacuum suction and mechanical deflection.

Techniques to Avoid Complications of Atrial Fibrillation Ablation

Atrial fibrillation ablation is an increasingly common procedure adapted by electrophysiologists across the world. Any procedure naturally comes with inherent risks of complications. The goal of this review is to elaborate latest techniques and strategies to avoid complications of ablation. There is increased focus on new tools for avoiding esophageal injury as well as minimizing phrenic nerve injury in addition to utilization of newer ablation technologies to address safer and effective ablation. A combination of improved patient selection and better treatment protocols combined with methods for early detection of complications will significantly reduce the incidence of complications. Newer innovative technologies like esophageal temperature monitoring, mechanical deviation, and integration of ablation parameters are helping to avoid or minimize collateral damage.

Prevention of left atrium esophagus fistula: Appraisal of existing technologies and strategies.

Catheter ablation has emerged as an effective treatment for atrial fibrillation (AF). Atrial esophageal fistula (AEF) is a rare, but feared complication. With increasing utilization of ablation therapy for AF, the understanding of the relationship between AEF and ablation has been improved in recent years. Efforts to reduce the risk of AEF have focused on decreasing the risk of severe esophageal injury (EI) and the presumed subsequent progression from EI to AEF, including esophageal temperature monitoring, esophageal cooling systems, esophageal deviation devices, and decreasing and/or curtailing ablation energy delivery. Periprocedural assessment may help identify higher risk patients and detect early esophageal lesions. This review systematically summarizes and evaluates the current strategies and techniques utilized to reduce the risk of AEF in the clinical workflow for AF ablation. We expect that this review will help clinicians to better understand the principles, advantages, and disadvantages of these methods, and to find suitable strategies using current available tools.

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.

Space-Occupying Lesions of the Retropharyngeal Space: An Anatomical Study With Application to Postoperative Retropharyngeal Hematomas.

Study Design:Cadaver study.Objective:The retropharyngeal space’s (RPS’s) clinical relevance is apparent in anterior cervical spine surgery with respect to postoperative hematoma, which can cause life-threatening airway obstruction. This cadaver study aims to establish guidance toward a better understanding of the tolerance of the RPS to accommodate fluid accumulation.Methods:Five fresh-frozen cadavers were dissected in the supine position. A digital manometer and a 20 Fr Foley catheter were inserted into the RPS via an anterolateral approach. While inflating the Foley catheter, the position of the esophagus/trachea was documented using fluoroscopy, and the retropharyngeal pressure was measured. We quantified the volume required to deviate the esophagus/trachea >1 cm from its original position using fluoroscopy. We also recorded the volume required to cause a visible change to the normal neck contour.Results:A mean volume of 12.5 mL (mean pressure 1.50 mm Hg) was needed to cause >1 cm of esophageal deviation. Tracheal deviation was encountered at a mean volume of 20.0 mL (mean pressure of 2.39 mm Hg). External visible clinical neck contour changes were apparent at a mean volume of 39 mL.Conclusion:A relatively small volume of fluid in the RPS can cause the esophagus/trachea to radiographically deviate. The esophagus is the structure in the RPS to be most influenced by mass effect. The mean volume of fluid required to cause clinically identifiable changes to the normal neck contour was nearly double the volume required to cause 1 cm of esophageal/tracheal deviation in a cadaver model.

Pulsed Field Ablation Versus Radiofrequency Ablation: Esophageal Injury in a Novel Porcine Model.

Pulsed field ablation (PFA) can be myocardium selective, potentially sparing the esophagus during left atrial ablation. In an in vivo porcine esophageal injury model, we compared the effects of newer biphasic PFA with radiofrequency ablation (RFA). In 10 animals, under general anesthesia, the lower esophagus was deflected toward the inferior vena cava using an esophageal deviation balloon, and ablation was performed from within the inferior vena cava at areas of esophageal contact. Four discrete esophageal sites were targeted in each animal: 6 animals received 8 PFA applications/site (2 kV, multispline catheter), and 4 animals received 6 clusters of irrigated RFA applications (30 W×30 seconds, 3.5 mm catheter). All animals were survived to 25 days, sacrificed, and the esophagus submitted for pathological examination, including 10 discrete histological sections/esophagus. The animals weight increased by 13.7±6.2% and 6.8±6.3% (P=0.343) in the PFA and RFA cohorts, respectively. No PFA animals (0 of 6, 0%) developed abnormal in-life observations, but 1 of 4 RFA animals (25%) developed fever and dyspnea. On necropsy, no PFA animals (0 of 6, 0%) demonstrated esophageal lesions. In contrast, esophageal injury occurred in all RFA animals (4 of 4, 100%; P=0.005): a mean of 1.5 mucosal lesions/animal (length, -21.8±8.9 mm; width, -4.9±1.4 mm) were observed, including one esophago-pulmonary fistula and deep esophageal ulcers in the other animals. Histological examination demonstrated tissue necrosis surrounded by acute and chronic inflammation and fibrosis. The necrotic RFA lesions involved multiple esophageal tissue layers with evidence of arteriolar medial thickening and fibrosis of periesophageal nerves. Abscess formation and full-thickness esophageal wall disruptions were seen in areas of perforation/fistula. In this novel porcine model of esophageal injury, biphasic PFA induced no chronic histopathologic esophageal changes, while RFA demonstrated a spectrum of esophageal lesions including fistula and deep esophageal ulcers and abscesses.

Ablation Approaches and Imaging Modalities to Lower Risk of Atrioesophageal Injury During Catheter Ablation for Atrial Fibrillation

Atrioesophageal fistula (AEF) is a rare yet catastrophic complication of atrial fibrillation (AF) ablation. Limited data exists on measures to prevent AEF. This review focuses on AF ablation approaches, esophageal protective strategies, and imaging modalities that can be utilized to reduce the risk of AEF. AEF has been reported to occur in less than 0.1% of AF ablation cases. Left untreated, it is associated with 100% mortality. Diagnosing AEF requires a high index of suspicion as symptoms are usually nonspecific. Several AF ablation techniques might reduce the risk of esophageal thermal injury (ETI): high-power short-duration radiofrequency ablation, implementation of time-to-isolation ablation strategy with cryoablation, and electroporation. Various esophageal protective approaches have been investigated. Although luminal esophageal temperature monitoring is widely used, data on its efficacy is conflicting. Esophageal cooling and esophageal deviation strategies have been shown to be effective in reducing the risk of ETI. Late gadolinium enhancement magnetic resonance imaging (LGE-MRI) is a noninvasive imaging modality that seems to have high sensitivity for detecting and quantifying the degree of ETI. Variable approaches have been reported to reduce the risk of esophageal injury. These approaches focus mainly on modulating ablation parameters and esophageal luminal temperature. Imaging modalities such as LGE-MRI can potentially identify early signs of ETI. Electroporation is a promising ablation technique that exhibits high tissue selectivity and can potentially reduce risk of esophageal injury.

Esophageal cooling for protection during left atrial ablation: a systematic review and meta-analysis

PurposeThermal damage to the esophagus is a risk from radiofrequency (RF) ablation of the left atrium for the treatment of atrial fibrillation (AF). The most extreme type of thermal injury results in atrio-esophageal fistula (AEF) and a correspondingly high mortality rate. Various strategies for reducing esophageal injury have been developed, including power reduction, esophageal deviation, and esophageal cooling. One method of esophageal cooling involves the direct instillation of cold water or saline into the esophagus during RF ablation. Although this method provides limited heat-extraction capacity, studies of it have suggested potential benefit. We sought to perform a meta-analysis of published studies evaluating the use of esophageal cooling via direct liquid instillation for the reduction of thermal injury during RF ablation.MethodsWe searched PubMed for studies that used esophageal cooling to protect the esophagus from thermal injury during RF ablation. We then performed a meta-analysis using a random effects model to calculate estimated effect size with 95% confidence intervals, with an outcome of esophageal lesions stratified by severity, as determined by post-procedure endoscopy.ResultsA total of 9 studies were identified and reviewed. After excluding preclinical and mathematical model studies, 3 were included in the meta-analysis, totaling 494 patients. Esophageal cooling showed a tendency to shift lesion severity downward, such that total lesions did not show a statistically significant change (OR 0.6, 95% CI 0.15 to 2.38). For high-grade lesions, a significant OR of 0.39 (95% CI 0.17 to 0.89) in favor of esophageal cooling was found, suggesting that esophageal cooling, even with a low-capacity thermal extraction technique, reduces the severity of lesions resulting from RF ablation.ConclusionsEsophageal cooling reduces the severity of the lesions that may result from RF ablation, even when relatively low heat extraction methods are used, such as the direct instillation of small volumes of cold liquid. Further investigation of this approach is warranted, particularly with higher heat extraction capacity techniques.

1786 Major Esophageal Bleeding Secondary to Mechanical Injury From Esophageal Deviation During Pulmonary Vein Isolation

INTRODUCTION: Radiofrequency catheter ablation and pulmonary vein isolation (PVI) are electrophysiologic interventions frequently performed for the management of atrial fibrillation (AF). Given the anatomic proximity of the esophagus and left atrium, the former is prone to thermal injury which can lead to peri-esophageal nerve injury, pain, dysphagia, and atrio-esophageal fistula formation. Mechanical deflection of the esophagus away from the ablation site is being used to minimize such complications. We present a case of major esophageal bleeding secondary to mechanical trauma in the setting of esophageal deviation during AF ablation. CASE DESCRIPTION/METHODS: 60 yo female with past medical history significant for obstructive sleep apnea, pulmonary hypertension, AF with multiple direct current cardioversion attempts, underwent elective PVI using an esophageal deviation stylet (EsoSure, Northeast Scientific, Waterbury, CT). After PVI, a small amount of blood was noted as a result of suction using an orogastric tube. CT chest ruled out esophageal pathology including perforation. Subsequent upper endoscopy showed small mucosal tears in middle third of esophagus and at the esophago-gastric junction (EGJ) (Figure 1). She was discharged on daily proton pump inhibitor and remained on anticoagulation. Five days later, she presented to the emergency room with complaints of weakness, fatigue, melena and non-radiating substernal sharp chest pain. Blood pressure was 64/35. Hemoglobin was 6.4 g/dL compared to 10.3 g/dL upon discharge. Shortly after arrival, the patient had an episode of large volume hematemesis. She was urgently intubated for airway protection and volume resuscitation was initiated. Emergent upper endoscopy reveled an actively bleeding superficial mucosal tear at the EGJ which was treated successfully with epinephrine injection followed by hemostatic clip placement (Figures 2 and 3). After transfusion of 3 units of packed red blood cells, repeat Hgb improved to 8.8 g/dL and remained stable. Patient was extubated, remained clinically stable and was discharged. DISCUSSION: Mechanical displacement of the esophagus away from an atrial ablation site is being used more frequently in electrophysiologic interventions, as it reduces ablation-related esophageal thermal injury. Despite newer esophageal retractors which retain less heat and are less bulky, vigilance should be practiced to avoid mechanical esophageal trauma.