Esophageal thermal lesions in radiofrequency ablation for atrial fibrillation: A prospective comparative study of thermal sensors.

BACKGROUND: Esophageal thermal lesion (ETL) is a complication of radiofrequency ablation for atrial fibrillation (RFAF). To prospectively compare the incidence of ETL, we used two linear, five- and three-sensor esophageal thermal monitoring catheters (ETMC5 and ETMC3). We also evaluated the predictors of ETL. METHODS: Patients receiving their first RFAF (n = 106) were randomized into two groups, ETMC5 (n = 52) and ETMC3 (n = 54). Ablation was followed by esophagogastroduodenoscopy within 3 days. RESULTS: Esophageal thermal lesion was detected in 7/106 (6.6%) patients (ETMC5: 3/52 [5.8%] vs. ETMC3: 4/54 [7.4%]; p = 1.0). The maximum temperature and number of measurements > 39.0°C did not differ between the groups (ETMC5: 40.5°C and 5.4 vs. ETMC3: 40.6°C and 4.9; p = .83 and p = .58, respectively). In ETMC5 group, the catheter had to be moved significantly less often (0.12 vs. 0.42; p = .0014) and fluoroscopy time was significantly shorter (79.2 min vs. 101.7 min; p = .0038) compared with ECMC3 group. The total number of ablations in ETMC5 group was significantly greater (50.2 vs. 37.7; p = .030) and ablation time was significantly longer (52.1 min vs. 40.1 min; p = .0039). Only body mass index (BMI) was significantly different between patients with and without ETL (21.4 ± 2.5 vs. 24.3 ± 3.4; p = .022). CONCLUSIONS: The incidence of ETL was comparable between ETMC5 and ETMC3 groups; however, fluoroscopy time, total ablation time, and total number of ablations differed significantly. Lower BMI may increase the risk of developing ETL.

Paradoxical Cerebral Air Embolism after Cardiac Ablation in Williams-Beuren Syndrome: A Clinico-Pathological Correlation.

Non-traumatic neurological deterioration is a medical emergency that may arise from diverse causes, to include cerebral infarction or intracranial hemorrhage, meningoencephalitis, seizure, hypoxic-ischemic or toxic/metabolic encephalopathy, poisoning, or drug intoxication. We describe the abrupt onset of neurological deterioration in a 53-year-old man with Williams-Beuren syndrome, a sporadically occurring genetic disorder caused by chromosomal microdeletion at 7q11.23. The clinical phenotype of Williams-Beuren syndrome is suggested by distinctive elfin facies, limited intellect, unique personality features, growth abnormalities, and endocrinopathies. The causative microdeletion of chromosomal material will frequently involve loss of the elastin gene, ELN, with resulting arteriopathy, supravalvular aortic stenosis, non-ischemic cardiopathy, and atrial fibrillation. Our patient sustained acute neurological decline within one month after undergoing a cardiac ablative procedure to convert atrial fibrillation to sinus rhythm. We present our findings in the setting of a clinico-pathological correlation, in which we reveal the cause of the abrupt neurological deterioration and discuss how our patient was affected by an uncommon stroke disorder.

Protection of the esophagus during catheter ablation of atrial fibrillation.

Esophageal injury still occurs with high frequency during ablation of atrial fibrillation (AF). The purpose of this study is to provide a review of methods to protect the esophagus from injury during AF ablation. Despite advances in imaging and ablation, the potential risk of esophageal injury during AF ablation remains an important concern with a high occurrence of esophageal injury (≈15%). There have been numerous studies evaluating varied techniques for esophageal protection including active cooling and displacement of the esophagus. These techniques are reviewed in this manuscript as well as the role of esophageal protection in managing patients undergoing AF ablation procedure.

Clinical presentation, diagnosis, and treatment of atrioesophageal fistula resulting from atrial fibrillation ablation.

BACKGROUND: Atrioesophageal fistula (AEF) is a worrisome complication of atrial fibrillation (AF) ablation. Its clinical manifestations and time course are unpredictable and may contribute to diagnostic and treatment delays. We conducted a systematic review of all available cases of AEF, aiming at characterizing clinical presentation, time course, diagnostic pitfalls, and outcomes. METHODS: The digital search retrieved 150 studies containing 257 cases, 238 (92.6%) of which with a confirmed diagnosis of AEF and 19 (7.4%) of pericardioesophageal fistula. RESULTS: The median time from ablation to symptom onset was 21 days (interquartile range [IQR]: 11-28). Neurological abnormalities were documented in 75% of patients. Compared to patients seen by a specialist, those evaluated at a walk-in clinic or community hospital had a significantly greater delay between symptom onset and hospital admission (median: 2.5 day [IQR: 1-8] vs. 1 day [IQR: 1-5); p = .03). Overall, 198 patients underwent a chest scan (computed tomography [CT]: 192 patients and magnetic resonance imaging [MRI]: 6 patients), 48 (24.2%; 46 CT and 2 MRI) of whom had normal/unremarkable findings. Time from hospital admission to diagnostic confirmation was significantly longer in patients with a first normal/unremarkable chest scan (p < .001). Overall mortality rate was 59.3% and 26.0% survivors had residual neurological deficits at the time of discharge. CONCLUSIONS: Since healthcare professionals of any specialty might be involved in treating AEF patients, awareness of the clinical manifestations, diagnostic pitfalls, and time course, as well as an early contact with the treating electrophysiologist for a coordinated interdisciplinary medical effort, are pivotal to prevent diagnostic delays and reduce mortality.

Atrio-esophageal Fistula Secondary to Atrial Fibrillation Ablation: A Case Report.

BACKGROUND: An atrio-esophageal fistula is an exceedingly rare but devastating complication of atrial fibrillation (AF) ablation procedures. Delays to diagnosis and definitive treatment herald a poor prognosis, with the development of catastrophic neurological injury or death secondary to cerebral air emboli. A high level of suspicion is essential to improve recognition of this rare but devastating condition. CASE REPORT: A 59-year-old man presented to the emergency department with an acute stroke and reduced consciousness. This presentation was preceded by an uncomplicated AF ablation 19 days prior and a subsequent emergency department attendance within a few days of his procedure, where he had presented with a history of new chest pain and reflux symptoms. Imaging revealed intra-cranial and intra-cardiac air, which was attributed to an uncontrolled atrio-esophageal fistula. Treatment options were limited by the patient's clinical instability and the patient was eventually palliated after developing catastrophic brain injury due to extensive cerebral air emboli. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Patients typically first present to the emergency department with new symptoms of either gastroesophageal reflux or chest pain, therefore, early recognition by emergency physicians is vital. Characteristic symptoms alongside a recent history of a cardiac ablation procedure should prompt additional diagnostic imaging to look for evidence of an atrio-esophageal fistula.

Low Incidence of Esophageal Lesions After Pulmonary Vein Isolation Using Contact-Force Sensing Catheter Without Esophageal Temperature Probe.

Pulmonary vein isolation (PVI) is a cornerstone therapy for atrial fibrillation (AF). Although severe complications are rather rare, the development of an atrio-esophageal fistula (AEF) is a fatal complication with a very high mortality even after surgical treatment. The use of esophageal temperature probes (ETP) during PVI may protect the esophagus but it is still under debate since the ETP may also lead to esophageal lesions. The aim of this study was to evaluate the clinical safety of PVI using contact-force (CF) sensing catheter without esophageal temperature monitoring.We investigated 70 consecutive patients who underwent point-by-point PVI without usage of ETP and who underwent esophago-gastro-duodenoscopy (EGD) with detailed evaluation of the esophagus after the index PVI procedure. The operator attempted to keep CF within the 10-40 g range. The incidences of esophageal lesions (EDEL) detected by endoscopy were then analyzed.Two of 70 patients (2.9%) showed EDEL consisting of one longitudinal ulcer-like erythematous lesion with fibrin and a different one consisting of a round-shaped lesion surrounded by erythema and petechial hemorrhage. All EDEL healed within two weeks under high proton-pump inhibitor therapy without developing AEF as proven by a second EGD of the esophagus.Point-by-point PVI without usage of ETP showed a low incidence of EDEL (2.9%); atrio-esophageal fistula was absent. Further studies on the necessity of ETP under CF control are necessary.

Atrioesophageal Fistula: A Rare but Dangerous Complication From Catheter Ablation.

Atrioesophageal fistula is a rare complication of catheter ablation. It can be discovered on computerized topography of the chest. It is a difficulty entity to diagnose and treat and carries a mortality between 67% and 100%. Management options include surgical repair and esophageal stenting. We report here a rare case of an atrioesophageal fistula that presented with massive upper gastrointestinal bleeding and hemiparalysis.

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.

Acute Cauda Equina Syndrome Caused by Epidural Steroid Injection in the Setting of a Spinal Dural Arteriovenous Fistula.

We present a case of acute cauda equina syndrome caused by an epidural steroid injection in the setting of a previously undiagnosed spinal dural arteriovenous fistula (SDAVF). Our patient was a 61-year-old man who presented to the emergency department with low back pain, inability to walk, paresthesias of his bilateral lower extremities, bowel and bladder incontinence, and saddle anesthesia. Physical examination revealed weakness and decreased sensation of the lower extremities as well as poor rectal tone and urinary retention. Magnetic resonance imaging (MRI) revealed evidence of spinal cord edema in the T9-10 region and a probable SDAVF with secondary distal thoracic cord ischemia. This case highlights the importance of prompt recognition of cauda equina syndrome in the emergency department, expedient imaging, and efficient transfers of care, which allowed this patient to quickly undergo necessary surgery that led to an almost complete recovery. It also highlights the importance of recognizing subtle changes on lumbar MRI.

[Rare but frequently lethal complication of pulmonary vein isolation]. / Seltene, aber oft tödliche Komplikation der Pulmonalvenenisolation.

A 65-year-old patient perceived dysphagia 4 days after uncomplicated pulmonary vein isolation; there were no other symptoms or complaints such as fever or malaise. Despite prophylactic treatment, a severe complication evolved which could be detected in time only by close control, allowing early treatment.

Atrioesophageal Fistula as a Complication of Radiofrequency Ablation for Atrial Fibrillation.

Atrioesophageal fistula (AEF) is an important complication of radiofrequency ablation (RFA). Delayed diagnosis is associated with increased morbidity and mortality. Despite the name "atrioesophageal fistula," fistulas functionally act esophageal to atrial, which accounts for the neurologic and infectious complications. This report presents the management of a 60-year-old male patient who was admitted to the emergency department (ED) with AEF-caused gastrointestinal bleeding. The patient was operated urgently, but he had serious comorbidities and died after the operation. The aim of this case was to evaluate patients who underwent RFA, within 10 days to two months, carefully in the ED and to know the possible complications.

Diffuse Cerebral Air Emboli After an Esophagogastroduodenoscopy One Month Post Left Atrial Ablation for Atrial Fibrillation.

We present a case of a patient who presented to the emergency department with vague abdominal pain one month after undergoing a left atrial ablation procedure for atrial fibrillation. While in the emergency department, the patient started to have episodes of hematemesis. Esophagogastroduodenoscopy (EGD) was performed and the patient become hypotensive and unresponsive after. Imaging confirmed atrioesophageal fistula and widespread cerebral air emboli and diffuse ischemia. Air emboli were likely introduced through the fistula during the EGD.

Esophageal Findings in the Setting of a Novel Preventive Strategy to Avoid Thermal Lesions during Hybrid Thoracoscopic Radiofrequency Ablation for Atrial Fibrillation.

Purpose The development of an atrio-esophageal fistula, a rare yet potentially lethal complication of ablation for atrial fibrillation, could be related to direct tissue heat transfer during and immediately after the ablation. We therefore studied the postoperative esophageal findings by esophagogastroduodenoscopy in patients that underwent a hybrid ablation procedure using a novel preventive strategy to avoid thermal lesions. Methods Thirty-four patients (28 males; 65 years ± 9 years) were retrospectively included. All underwent a hybrid ablation in our center between April 2015 and November 2019 and agreed to an esophagogastroduodenoscopy within 0-14 days (mean: 5 days) following the ablation. To reduce the incidence of thermal lesions three procedural preventive strategies were introduced: (i) videoscopic intrathoracic transesophageal echocardiographic probe visualization to understand the relationship between posterior left atrial wall and esophagus, with probe retraction before ablation; (ii) lifting the cardiac tissue away from the esophagus during energy application; and (iii) a 30-s cool-off period after energy delivery with irrigation of the device, the ablated tissue, and the surrounding tissues. Results No esophageal thermal lesions were observed. One third of patients were diagnosed with incidental esophageal findings unrelated to the ablation procedure (11; 32.4%). Conclusion Novel preventive strategies by visualization and by avoiding contact between the ablation catheter or ablated tissue and the pericardium, seems to eliminate the potential risk of esophageal thermal lesions in the setting of hybrid ablation. Since one third of patients had preexisting esophageal disease, a more comprehensive pre-operative screening could be important to reduce the risk.

Intraluminal Esophageal Temperature Monitoring Using the Circa S-Cath™ Temperature Probe to Guide Left Atrial Ablation in Patients with Atrial Fibrillation.

INTRODUCTION: Radiofrequency catheter ablation is a common treatment for atrial fibrillation (AF), during which thermal esophageal injury may rarely occur and lead to an atrio-esophageal fistula. Therefore, we studied the utility of the Circa S-Cath™ multi-sensor luminal esophageal temperature (LET) probe to prevent esophageal thermal injury. METHODS AND RESULTS: Thirty-six patients, enrolled prospectively, underwent circumferential or segmental pulmonary vein isolation for treatment of AF. A maximum ablation electrode temperature of 42ºC was programmed for automatic power delivery cutoff. In addition, energy delivery was manually discontinued when the maximum LET on any sensor of the probe rose abruptly (i.e. ˃0.2ºC) or exceeded 39º C. Esophagoscopy was performed immediately after ablation in 18 patients (with the temperature probe still in place) and at approximately 24 hours after ablation in 18 patients. Esophageal lesions were classified as likely traumatic or thermally related. Of the 36 patients enrolled in the study, 21 had persistent and 15 had paroxysmal AF, average LVEF 57±16% and CHA2DS2VASc score 1.6±1.2 (range 0-4). Average maximum LET was 37.8±1.4ºC, power delivery 31.1±8 watts and ablation electrode temperature 36.4±4.1ºC. Average maximum contact force was 44.5±20.5 grams where measured. Only 1 patient (<3%) had an esophageal lesion that could potentially represent thermal injury and 4 patients (11.1%) had minor traumatic mechanical injury. CONCLUSIONS: LET guided titration of power and duration of energy application, using an insulated multi-sensor esophageal temperature probe, is associated with a low risk of esophageal thermal injury during AF ablation. In only rare cases, LET monitoring resulted in the need to manipulate the esophagus to avoid unacceptable temperature rises, that could not be achieved by adjustment of power and duration of energy application.

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

PURPOSE: Thermal 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. METHODS: We 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. RESULTS: A 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. CONCLUSIONS: Esophageal 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.

Esophageal cooling for protection: an innovative tool that improves the safety of atrial fibrillation ablation.

This letter to the editor concerns the article: 'Innovative tools for atrial fibrillation ablation' by Rottner et al., published in the journal on 13th of May 2020. We read the article with great interest and congratulate the authors on an impressively detailed summary of the current tools and technological advances in atrial fibrillation ablation. Improving the safety of this procedure is very important due to widespread clinical practice and the increasing demand for this procedure. We would like to share further discussion with the authors and the journal's readership on current advances in improving the safety of this procedure - esophageal cooling. The results of a large randomized trial was recently presented, the IMPACT study (NCT03819946), which showed that a simple, standardized method of esophageal cooling with the ensoETM® device can significantly reduce esophageal thermal injury by 83.4%. Esophageal protection is important as esophageal injury has a high mortality rate to those that sustain this injury although the overall incidence is low. Rottner et al. discuss a much smaller study on esophageal cooling and the limitations of this study are also discussed.

Feasibility, safety, and efficacy of a novel preshaped nitinol esophageal deviator to successfully deflect the esophagus and ablate left atrium without esophageal temperature rise during atrial fibrillation ablation: The DEFLECT GUT study.

BACKGROUND: Esophageal thermal injury is a feared complication of radiofrequency ablation for atrial fibrillation (AF). Rise in luminal esophageal temperature (LET) limits the ability to deliver radiofrequency energy on the posterior wall of the left atrium. OBJECTIVE: The purpose of this study was to evaluate the feasibility, safety, and efficacy of a mechanical esophageal deviation (ED) tool during AF ablation. METHODS: We evaluated 687 patients who underwent radiofrequency ablation for AF. In 209 patients, the EsoSure (Northeast Scientific) was used to deflect the esophagus away from the ablation site. Propensity score matching was performed to obtain 180 patients each in the ED and non-ED arms. ED was used for LET rise seen in 61.7% of patients (111/180) and was used if the esophagus was in the line of ablation on fluoroscopy in 38.3% of patients (69/180). RESULTS: Mean deviation of trailing edge of esophagus with EsoSure was 2.45 ± 0.9 cm (range 1-4.5). LET rise >1°C was significantly lower in the ED than non-ED group (3% vs 79.4%; P <.001). Mean LET rise was also lower in the ED arm (ED 0.34 ± 0.59 vs non-ED 1.66 ± 0.54; P <.001). Intraprocedural success of pulmonary vein antral isolation, was slightly improved in the ED arm than in the non-ED arm without statistical significance. AF recurrence was lower in the ED arm at 3-month, 6-month, and 1-year follow-up than in the non-ED arm. No ED-related complications were noted. CONCLUSION: Mechanical displacement of the esophagus with EsoSure seems to be feasible, safe, and efficacious in enabling adequate radiofrequency energy delivery to the posterior wall of the left atrium without significant LET rise and obvious clinical signs of esophageal injury.

Management of Atrio-Esophageal Fistula Following Left Atrial Ablation.

Currently, no guidelines have been established for the treatment of atrio-esophageal fistula (AEF) secondary to left atrial ablation therapy. After comprehensive literature review, we aim to make suggestions on the management of this complex complication and also present a case series. We performed a review of the existing literature on AEF in the setting of atrial ablation. Using keywords atrial fibrillation, atrial ablation, fistula formation, atrio-esophageal fistula, complications, interventions, and prognosis, a search was made using the medical databases PUBMED and MEDLINE for reports in English from 2000 to April 2015. A statistical analysis was performed to compare the three different intervention arms: medical management, stent placement and surgical intervention. The results of our systematic review confirm the high mortality rate associated with AEF following left atrial ablation and the necessity to diagnose atrio-esophageal injury in a timely manner. The mortality rates of this complication are 96% with medical management alone, 100% with stent placement, and 33 % with surgical intervention. Atrio-esophageal injury and subsequent AEF is an infrequent but potentially fatal complication of atrial ablation. Early, prompt, and definitive surgical intervention is the treatment of choice.

Difference in thermodynamics between two types of esophageal temperature probes: Insights from an experimental study.

BACKGROUND: Luminal esophageal temperature monitoring is performed with a variety of temperature probes, but little is known about the relationship between the structure of a given probe and its thermodynamic characteristics. OBJECTIVE: The purpose of this study was to evaluate the difference in thermodynamics between a 9Fr standard esophageal probe and an 18Fr esophageal stethoscope. METHODS: In the experimental setting, each probe was submerged in a constant temperature water bath maintained at 42°C; in the patient setting, we monitored the temperature with both probes at the same time. RESULTS: The time constant of the stethoscope was higher than that of the probe (33.5 vs 8.3 s). Compared to the probe, the mean temperature measured by the stethoscope at 10 seconds was significantly lower (22.5°C ± 0.4°C vs 33.5°C ± 0.3°C, P<.0001), whereas the time to reach the peak temperature was significantly longer (132.6 ± 5.9 s vs 38.8 ± 1.0 s, P<.0001). Even in the ablation cases we observed that when the esophageal probe reached a peak temperature of 39.6°C ± 0.3°C, the esophageal stethoscope still displayed a temperature of 37.3°C ± 0.2°C (a mean of 2.39°C ± 0.3°C lower, P<.0001), showing a <0.5°C increase in temperature half of the times. CONCLUSION: The 18Fr esophageal stethoscope has a significantly slower time response compared to the 9Fr esophageal probe. In the clinical setting, this might result in a considerable underestimation of the luminal esophageal temperature with potentially fatal consequences.