Atrioesophageal Fistula in the Era of Atrial Fibrillation Ablation: A Review

2023 Cardiac Society of Australia and New Zealand Expert Position Statement on Catheter and Surgical Ablation for Atrial Fibrillation

Catheter ablation for atrial fibrillation (AF) has increased exponentially in many developed countries, including Australia and New Zealand. This Expert Position Statement on Catheter and Surgical Ablation for Atrial Fibrillation from the Cardiac Society of Australia and New Zealand (CSANZ) recognises healthcare factors, expertise and expenditure relevant to the Australian and New Zealand healthcare environments including considerations of potential implications for First Nations Peoples. The statement is cognisant of international advice but tailored to local conditions and populations, and is intended to be used by electrophysiologists, cardiologists and general physicians across all disciplines caring for patients with AF. They are also intended to provide guidance to healthcare facilities seeking to establish or maintain catheter ablation for AF.

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.

Atrio-Esophageal Fistula: A Rare Entity Complicating a Common Procedure

A 66-year-old female with a history of radiofrequency ablation for atrial fibrillation presented with hematemesis and fever. A CT chest revealed an atrio-esophageal fistula (AEF) and a CT head showed bilateral septic emboli. Blood cultures were positive for Streptococcus sanguinis. She underwent primary repair of the atrial defect on cardiopulmonary bypass where a large atrial vegetation was retrieved, followed by a right thoracotomy with the closure of the esophageal defect the next day. She was discharged to a rehabilitation facility after 18 days of hospital stay with a 6 weeks antibiotics plan. The incidence of AEF following ablation procedures has been estimated at 0.01 to 0.04%, and the pathogenesis is linked to direct tissue and vagus nerve injury. The most common clinical findings are fever and neurologic deficits. CT chest is the best diagnostic modality. CT head might demonstrate embolic phenomena and TTE can show vegetation. Early surgical intervention, even in an unstable patient, is paramount for survival.

Gastrointestinal Bleeding Caused by Atrioesophageal Fistula Secondary to Atrial Fibrillation Ablation

We present the case of a patient with upper gastrointestinal bleeding caused by an atrioesophageal fistula secondary to radiofrequency ablation for the treatment of refractory atrial fibrillation. Atrioesophageal fistula is a rare but serious complication. The endoscopic treatment is not established in the case of vascular-enteric fistulas and is still a challenge for endoscopists, which requires in most cases a multidisciplinary approach.

Atrioesophageal fistula: A rare complication of catheter ablation for atrial fibrillation

ABSTRACT

Atrioesophageal fistula with resulting air emboli is a rare but potentially fatal complication of radiofrequency catheter ablation (RFCA) for atrial fibrillation. Patients typically present within 60 days after RFCA with fever, neurologic deficits, chest pain, and gastrointestinal bleeding. Chest CT with IV contrast reveals the atrioesophageal fistula in most cases, and CT of the head or MRI of the brain commonly reveals signs of air emboli. Early diagnosis, initiation of antibiotics, and immediate surgical intervention may improve patients' chances of survival.

Prevalence and characteristics of transesophageal echocardiography-related esophageal mucosal injury in patients with atrial fibrillation who underwent pulmonary vein isolation

BACKGROUND

Transesophageal echocardiography (TEE) is the gold standard for detecting thrombi in the left atrium (LA) and left atrial appendage (LAA) prior to pulmonary vein isolation (PVI) for the treatment of atrial fibrillation (AF). Although TEE has a good safety profile, it was recently reported that TEE preceding PVI can cause esophageal mucosal injuries (EMIs). The exact mechanism remains to be elucidated. In the present study, we investigated the incidence and risk factors of TEE-related EMI (TEE-EMI) among patients who underwent PVI for AF.

METHODS AND RESULTS

This study included 262 consecutive patients who underwent PVI with preoperative TEE using a 3D TEE probe and postoperative esophagogastroduodenoscopy. TEE-EMIs were observed in 16 (6.1%) patients (18 lesions), whereas PVI-related EMIs were found in 5 (1.9%) patients (8 lesions). All TEE-EMIs were observed in the upper or middle esophagus and occurred more frequently in the right region of the upper esophagus and the left anterior region of the middle esophagus; only one patient experienced mild chest discomfort. In the multivariate analysis, advanced age was an independent risk factor for TEE-EMIs (odds ratio 1.08, 95% confidence interval 1.01-1.16; P = 0.0274).

CONCLUSIONS

The incidence of TEE-EMIs with 3D TEE probes was relatively high in the upper or middle esophagus, anatomically close to the LA, among patients who underwent PVI. Advanced age could pose a significant risk. These findings may warrant consideration of other methods to rule out LA/LAA thrombi, especially in elderly patients.

Autopsy Techniques in Patients With History of Radiofrequency Ablation for Atrial Fibrillation

CONTEXT.—

Esophageal fistula formation is one of the most feared complications of radiofrequency catheter ablation. This procedure and its many variations, such as the "maze," are becoming the mainstream treatment for atrial fibrillation owing to limitations of antiarrhythmic drugs. The incidence of this complication rate has been reported to be from 0.01% to 1%.

OBJECTIVE.—

To delineate the importance of using the en bloc Letulle method of dissection for identifying esophageal fistulas for cases with a history of radiofrequency catheter ablation.

DESIGN.—

Six autopsy cases with a history of radiofrequency catheter ablation for atrial fibrillation were selected from 1736 autopsies performed between 2009 and 2020.

RESULTS.—

The initial presenting symptoms included neurologic symptoms, chest pains, epigastric discomfort, and sepsis. Transesophageal echocardiogram of 4 cases showed no evidence of thrombus or vegetation, however, 2 cases had evidence of atrial esophageal fistula. The autopsy findings included 5 atrial esophageal fistulas and 1 esophagopericardial fistula. Atrial esophageal fistulas were small and could be detected without difficulty when the en bloc Letulle technique was used and would have been easily missed by the Virchow method. The immediate causes of the deaths were myocardial ischemia, septic emboli to brain and heart, hypovolemic shock secondary to exsanguination, stroke, and coagulopathy.

CONCLUSIONS.—

To date, this is the largest collection of autopsy cases showing esophageal fistula associated with prior radiofrequency catheter ablation. The Letulle dissection method is preferable in this setting.

Left atrio-oesophageal fistula after atrial fibrillation ablation

We report a case of a 68-year-old woman who presented with atypical chest pain and fluctuating neurological symptoms 4 weeks after cryoballoon ablation procedure for atrial fibrillation. Brain imaging showed multiple embolic infarcts, while the chest imaging revealed an abnormal connection between the posterior wall of the left atrium and the oesophagus. Based on her clinical presentation and the imaging findings, a diagnosis of left atrio-oesophageal fistula (AOF) was established. AOF carries a high mortality rate unless an urgent surgical repair is performed. Oesophageal instrumentation for an echocardiogram or endoscopy should be avoided as it can result in massive air embolus, causing stroke or death.

Atrioesophageal fistula with meningitis: A rare complication of atrial fibrillation ablation, case report and literature review

Atrioesophageal fistula is a rare, devastating complication of atrial fibrillation ablation, reportedly occurring in 0.015–0.04% of catheter ablations. A 66-year-old African American male with a past medical history of chronic atrial fibrillation status post recent radiofrequency ablation and on chronic anticoagulation with rivaroxaban presented with left upper extremity numbness, tingling, and transient weakness. He was admitted for a cerebrovascular accident workup; a 12-lead electrocardiogram revealed atrial fibrillation and magnetic resonance imaging of the brain was consistent with multifocal embolic infarcts. Hospital course was further complicated by persistent high-grade fevers, gram-positive bacteremia, and worsening mental status requiring mechanical ventilation. Lumbar puncture was consistent with bacterial meningitis. Transthoracic echocardiogram was negative for vegetations. Computed tomography angiography of the chest with intravenous contrast revealed an outpouching off the posterior wall of the left atrium at the level of the inferior pulmonary vein, consistent with an atrioesophageal fistula. We present this case to highlight the clinical features of a rare but potentially fatal complication from a commonly performed procedure requiring prompt recognition and life-saving intervention.

•

Atrioesophageal fistula (AEF) is a rare, devastating complication of atrial fibrillation ablation.

•

AEF-related complications vary in presentation and should be suspected within three-months of radiofrequency ablation.

•

Repeat imaging is reasonable in patients with high clinical suspicion.

•

Treatment options include surgical repair and conservative management with esophageal stenting.

Prevention and Treatment of Atrioesophageal Fistula Related to Catheter Ablation for Atrial Fibrillation

Atrioesophageal fistula (AEF) is an uncommon but devastating complication of catheter ablation for atrial fibrillation. Even with appropriate recognition and treatment, mortality is greater than 30% in most studies. If AEF is suspected, it is essential to avoid endoscopy and to order immediate cross-sectional imaging. If the diagnosis is confirmed, a thoracic surgeon should be promptly notified and must assess the patient urgently. The prognosis for AEF is poor even if it is appropriately recognized and addressed, so prevention must be a high priority. Prevention of AEF should involve the use of low-risk and cost-effective measures during ablation, which may increase safety, efficacy, or both. These strategies may include conscious sedation (as opposed to general anesthesia), low-power ablation, low-flow irrigation, short-duration lesions, esophageal temperature measurement, esophageal deviation, and pharmacologic prophylaxis with proton pump inhibitors or histamine H₂ receptor blockers. Multiple new technologies are now becoming available, which may further reduce esophageal injury. Proceduralists should be aware of the available techniques and equipment that may help to reduce the risk of AEF, while simultaneously considering the possibility of unintended consequences.

An Insight to the Role of Thermal Effects on the Onset of Atrioesophageal Fistula: A Computer Model of Open-Irrigated Radiofrequency Ablation

PURPOSE

Atrial fibrillation (AF) is the most common heart rhythm disorder in the world. Radiofrequency catheter ablation (RFCA) has become the preferred method of treatment for drug-refractory AF. One of the rare (< 0.2%) but deadly (≈ 80%) complications of RFCA is Atrioesophageal fistula (AEF). Although the exact pathophysiological events in developing AEF are not fully understood, one hypothesis is that the underlying cause may be thermal damage to the mucosa (the esophagus lumen).

METHOD

The present study reports on a computer model of RFCA in the posterior wall of the left atrium (LA) which is in close proximity to the esophagus. A novel systematic approach was taken by considering a range of anatomical variations (obtained from clinical data) to study the spatial and temporal temperature data when RF energy was applied to cause a threshold temperature of 50 °C in the mucosa. The model is also used to investigate the spatial and temporal changes in mucosal temperature that may affect the reliability of the readings from esophageal temperature monitoring devices if they are not positioned accurately.

RESULTS

The results suggest evidence of transmural esophageal lesions in all the anatomies except one, if the 50 °C temperature threshold is the only criteria used for identification of thermal damage. However, by taking into consideration the effect of time (temperature-time integral), only some anatomies were identified as being partially damaged. Investigating the temperature and the temperature gradient data during the ablation revealed that the increases in both the temperature and the temperature gradient were time, location and anatomy dependent. This finding may have significance in the design and development of next-generation temperature monitoring devices that will provide a temperature map rather than single point measurements.

CONCLUSION

Studies such as the present work may provide more convenient platforms for investigating the effect of the many factors involved in the RF procedure and how they may link to the development of AEF.

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.

Prevention of Esophageal Damage During Ablation of Atrial Fibrillation by the Esophagus Mechanical Deviation

Atrial fibrillation is the most prevalent arrhythmia in the world population. Despite the use of antiarrhythmics, it is difficult to control clinically, causing symptoms and mainly generating risk of a thromboembolic event. Since 1998, by means of radiofrequency ablation, the treatment of atrial fibrillation has completely changed, but together with this important evolution complications from this ablative treatment technique have also started. In addition to the pulmonary vein stenosis caused by the ablation and later corrected with the change in the technique, atrioesophageal fistulas appeared due to the application of radiofrequency in the posterior wall of the left atrium. This wall is very close (0.5 cm onaverage) to the esophagus, which facilitates the formation of the fistula that leads to the death of almost 100% of the affected patients, despite the various treatment measurements already developed. To avoid this serious complication, several authors have created techniques to protect the esophagus including its mechanical deviation to a region opposite to the radiofrequency application, taking advantage of its mobility and easiness of handling. The mechanical deviation of the esophagus has proven to be the simplest, cheapest and most efficient way to protect this organ from radiofrequency thermal damage during atrial fibrillation ablation.

Prevenção de Dano Esofágico Durante Ablação de Fibrilação Atrial por Desvio Mecânico do Esôfago

A fibrilação atrial é a arritmia de maior prevalência na população mundial. Apesar do uso de antiarrítmicos, é de difícil controle clínico, ocasionando sintomas e principalmente gerando risco de um evento tromboembólico. A partir de 1998, por meio da ablação por radiofrequência, o tratamento da fibrilação atrial mudou completamente, porém junto a essa importante evolução também iniciaram as complicações advindas dessa técnica de tratamento ablativo. Além das estenoses das veias pulmonares causadas pela ablação e posteriormente corrigidas com a mudança da técnica, surgiram as fístulas átrio-esofágicas, devido à aplicação de radiofrequência na parede posterior do átrio esquerdo. Esta parede está bem próxima (0,5 cm em média) do esôfago, facilitando a formação da fístula que leva à morte quase 100% dos pacientes acometidos, apesar das diversas medidas de tratamento já desenvolvidas. Para evitar essa grave complicação, vários autores criaram técnicas para proteger o esôfago incluindo seu desvio mecânico para uma região oposta à da aplicação de radiofrequência, aproveitando a sua mobilidade e facilidadede abordagem. O desvio mecânico do esôfago tem se mostrado a forma mais simples, barata e eficiente de proteger esse órgão da lesão térmica da radiofrequência durante a ablação da fibrilação atrial.

Cerebral arterial air embolism secondary to iatrogenic left atrial-esophageal fistula: a case report

Background

Cerebral arterial air embolism is a life-threatening complication that can result in neurologic deficits or death. Sometimes it is iatrogenic, presented as a complication of invasive medical procedures. Here we describe a case of cerebral arterial air embolism secondary to iatrogenic left atrial-esophageal fistula, of which the diagnosis might be covered up by the complicated pathophysiologic changes.

Case presentation

A 68-year-old man presented with unconsciousness hours after aphasia and right hemiplegia, accompanied with hematemesis and fever. He had a history of atrial fibrillation, treated by radiofrequency catheter ablation 1 month ago. Brain CT displayed massive air embolism in left hemisphere, as well as right parietal lobe. Chest CT demonstrated a focus of air in the left atrium, which highly suggested an atrial-esophageal fistula. The patient received high flow (6 L/min) oxygen therapy. Intravenous antibiotics including imipenem and vancomycin were administered together with crystalloid rehydration. Supportive therapies were given including intubation, mechanical ventilation and vasopressor use. Because of the patient’s unstable condition and poor prognosis, surgical repair was considered but not pursued. The patient presented a very fast deterioration of cardiac function and circulatory failure, and finally died from cardiac arrest.

Conclusions

Clinicians must have a high index of suspicion for atrial-esophageal fistula for patients presenting with chest discomfort, new onset of stroke, upper gastrointestinal bleeding, and development of sepsis as long as 50 days after the ablation for atrial fibrillation. Urgent CT can ultimately establish the diagnosis in most cases.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

Encephalitis as a complication of a spinal-esophageal fistula due to discitis

In patients with back or scapular pain, if there is evidence of neurological symptoms, fever, chills, malaise, or other signs of infection, the work-up should consider the possibility of a spinal-esophageal fistula.

Atrioesophageal Fistula After Radiofrequency Ablation Presenting With Status Epilepticus: A Case Report

Radiofrequency (RF) ablation for atrial fibrillation is commonly performed. Atrioesophageal fistulas are an uncommon complication of RF ablation and can present with status epilepticus due to an extensive vascular air embolus. Initial treatment may require a high level of suspicion of this rare occurrence to help prevent further injury and increase the likelihood of a meaningful recovery.

Acute Stroke After Upper Endoscopy in a Patient With a Suspected Atrioesophageal Fistula

Atrioesophageal fistula (AEF) is a rare complication of atrial fibrillation ablation. We present a man with sepsis and frank hematemesis 3 weeks after atrial fibrillation ablation. Thoracic computed tomography showed no definitive evidence of AEF. He underwent esophagogastroduodenoscopy and subsequently developed an embolic stroke. In the operating room, he was found to have AEF. This case highlights the importance of maintaining a high index of suspicion for AEF because of its nonspecific presentation and difficulty in diagnosing with imaging or endoscopy. Once AEF is suspected, esophagogastroduodenoscopy should be avoided because of the risk of precipitating embolic events.

Lessons of the month 1: Fatal oesophago-pericardial fistula with cerebral air embolism after elective atrial fibrillation ablation

Oesophago-pericardial fistula following any electrophysiological procedure is a rare, and potentially, life-threatening condition. Initial presentation can easily be misdiagnosed, as symptoms vary and are not specific. Echocardiography is an invaluable tool to diagnose and rule out complications. We present the case of a 68-year-old patient who developed an oesophago-pericardial fistula complicated with purulent pericarditis, sepsis and cerebral air embolism. In conclusion, this case report encourages physicians to use strategies that may help with early diagnosis and lead to potential lifesaving interventions.

Fatal esophageal-pericardial fistula as a complication of radiofrequency catheter ablation

The clinical role of catheter ablation using radiofrequency or cryothermal energy has become an important therapy in the management of patients with recurrent or persistent tachyarrhythmia that is refractory to medical therapy. It is regarded as a safe and reliable procedure and is performed routinely in health care facilities across the country. Like all procedures, there are associated risks and benefits. Development of an esophageal-atrial fistula is a rare but often-fatal complication of radiofrequency ablation. It is the second most frequent cause of death caused by the procedure, with mortality rates in excess of 70%. Death usually occurs as a result of cerebral or myocardial air embolism, endocarditis, massive gastrointestinal bleeding, and/or septic shock. Electrophysiologists have instituted a number of safeguard techniques to diminish the risk of developing esophageal-atrial fistula. Despite these measurements, instances of fistulous development still occur. Herein, we report a case of a 74-year-old male who presented with chest pain secondary to esophageal-pericardial fistula 19 days after pulmonary vein isolation using radiofrequency energy for atrial fibrillation in order to illustrate the clinical variability and diagnostic challenges associated with this dreaded gastrointestinal complication.

Protecting the esophagus from thermal injury during radiofrequency ablation with an esophageal cooling device

Purpose

We sought to quantify the capabilities of a commercially available cooling device to protect the esophagus from RF injury in an animal model and develop a mathematical model to describe the system and provide a framework from which to advance this technology.

Methods

A series of ablations (10 W, duration 30-45 seconds) were performed directly on exposed swine esophagus. Control ablations were performed with static 37°C water, and treatment ablations were performed with water (range 5°C-37°C) circulating within the device. Mucosal lesions were evaluated visually and with target tissue histology. A mathematical model was then developed and compared against the experimental data.

Results

All 23 ablations (100%) performed under control conditions produced visible external esophageal lesions; 12 of these (52%) were transmural. Under treatment conditions, only 5 of 23 ablations (22%) produced visible external lesions; none (0%) were transmural. Transmurality of lesions decreased as circulating water temperature decreased, with absolute reduction ranging from 5.1% with the use of 37°C water (p=0.7) to 44.5% with the use of 5°C water (p<0.001). Comparison to the mathematical model showed an R^2 of 0.75, representing good agreement.

Conclusion

Under worst-case conditions, with RF energy applied directly to the adventitial side of the esophagus, internal esophageal cooling with an esophageal cooling device provides significant protective effect from thermal injury. A mathematical model of the process provides a means to further investigate this approach to preventing esophageal injury during RF ablation and can serve to guide ongoing clinical investigations currently in progress.

Incidence of complications related to catheter ablation of atrial fibrillation and atrial flutter: a nationwide in-hospital analysis of administrative data for Germany in 2014

Aims

Risks of catheter ablation for atrial fibrillation and flutter assessed in retrospective studies, registries, and controlled trials may underestimate 'real world' conditions.

Methods and results

To assess complications in a nationwide approach, we included all cases undergoing catheter ablation for atrial fibrillation and atrial flutter in Germany in 2014, using ICD-10-GM-based German Diagnosis Related Group (G-DRG) codes and the well differentiated German Operation and Procedure Classification (OPS) analysing 33 353 in-hospital cases. For left atrial ablations (19 514 cases), the overall complication rate ranged from a mean of 11.7% to 13.8% depending on type and site of applied energy, including major complications ranging from 3.8% to 7.2%. Whereas overall complication rates were lower for atrial flutter ablations (13 871 cases, 10.5%; P < 0.001), interestingly, major complications occurred more frequently (7.4%; P < 0.001). Particularly, in-hospital death was four-times more common following right than following left atrial ablations (47 vs. 18 cases, 0.34% vs. 0.09%; P < 0.001). Stratified by centre ablation volume, significantly fewer overall complications occurred in centres performing >100 vs. ≤100 left atrial ablations annually (12.7% vs. 16.4%; P < 0.002).

Conclusion

Administrative data of all atrial fibrillation ablations in Germany in 2014 revealed higher overall and major complication rates than previously reported. Few patients were treated in low volume centres, but were exposed to a higher overall complication risk. Atrial flutter ablations were associated with surprisingly high rates of life-threatening complications. Advanced age combined with highly prevalent cardiac, pulmonary and, vascular comorbidities likely play a major role. In addition, individual-level clinical studies need to address the safety and benefits of catheter ablation in an elderly, diseased population.

Atrioesophageal Fistula: Considerations for the neurological clinician

Atrioesophageal fistula (AEF) is a rare complication of cardiac ablation for atrial fibrillation. It can present in many ways, but neurological signs and symptoms are common initial signs sometimes resulting in neurosurgeons and neurologists first evaluating patients with the condition. We present a case report of at 68-year-old female who presented with acute stroke symptoms and multifocal hemorrhages on MRI who was worked up through our neurosurgery department and diagnosed with AEF. This case highlights three clues to alert neurological clinicians to AEF as a possible diagnosis; clinical worsening of neurological symptoms in correlation to episodes of emesis, septic emboli on CT/MRI, and bacteremia caused by a gram positive oral or GI flora. If neurological clinicians encounter these red flags, an immediate CT of the chest and abdomen and consultation with cardiothoracic surgery may be life-saving.

The Impact of Advances in Atrial Fibrillation Ablation Devices on the Incidence and Prevention of Complications

The number of patients with atrial fibrillation currently referred for catheter ablation is increasing. However, the number of trained operators and the capacity of many electrophysiology labs are limited. Accordingly, a steeper learning curve and technical advances for efficient and safe ablation are desirable. During the last decades several catheter-based ablation devices have been developed and adapted to improve not only lesion durability, but also safety profiles, to shorten procedure time and to reduce radiation exposure. The goal of this review is to summarise the reported incidence of complications, considering device-related specific aspects for point-by-point, multi-electrode and balloon-based devices for pulmonary vein isolation. Recent technical and procedural developments aimed at reducing procedural risks and complications rates will be reviewed. In addition, the impact of technical advances on procedural outcome, procedural length and radiation exposure will be discussed.

Relation between denaturation time measured by optical coherence reflectometry and thermal lesion depth during radiofrequency cardiac ablation: Feasibility numerical study

BACKGROUND/OBJECTIVE

Radiofrequency (RF) catheter ablation is a minimally invasive medical procedure used to thermally destroy the focus of cardiac arrhythmias. Novel optical techniques are now being integrated into RF catheters in order to detect the changes in tissue properties. Loss of birefringence due to fiber denaturation at around 70°C is related to changes in accumulated phase retardation and can be measured by polarization-sensitive optical coherence reflectometry (PS-OCR). Since irreversible thermal lesions are produced when the tissue reaches 50°C, our goal was to seek the mathematical relationship between both isotherms.

MATERIALS AND METHODS

A two-dimensional model based on a coupled electric-thermal problem was built and solved using the finite element method. The model consisted of cardiac tissue, blood, and a non-irrigated electrode with a sensor embedded in its tip to maintain a specific target electrode temperature. Computer simulations were conducted by varying the tissue characteristics. Lesion depth was estimated by the 50°C isotherm, while the denaturation time (TD) was taken as the time at which the 70°C isotherm reached a depth of 0.75 mm (which corresponds to the optical depth reached by PS-OCR technology).

RESULTS

A strong correlation (R²  > 0.83) was found between TD and lesion depth and an even stronger correlation (R² > 0.96) was found between TD and the time required to achieve a specific lesion depth. For instance, the ablation time required to ensure a minimum lesion depth of 3 mm was 1.33 × TD + 3.93 × seconds.

CONCLUSIONS

The computer results confirmed the strong relationship between denaturation time and lesion depth and suggest that measuring denaturation time by PS-OCR could provide information on the ablation time required to reach a specific lesion depth. Lasers Surg. Med. 50:222-229, 2018. © 2017 Wiley Periodicals, Inc.

Atrioesophageal Fistula: Clinical Presentation, Procedural Characteristics, Diagnostic Investigations, and Treatment Outcomes

BACKGROUND

Percutaneous or surgical ablation are increasingly used worldwide in the management of atrial fibrillation. The development of atrioesophageal fistula (AEF) is among the most serious and lethal complications of atrial fibrillation ablation. We sought to characterize the clinical presentation, procedural characteristics, diagnostic investigations, and treatment outcomes of all reported cases of AEF.

METHODS AND RESULTS

Electronic searches were conducted in PubMed and Embase for English scientific literature articles. Out of 628 references, 120 cases of AEF were identified using various ablation modalities. Clinical presentation occurred between 0 and 60 days postablation (median 21 days). Fever (73%), neurological (72%), gastrointestinal (41%), and cardiac (40%) symptoms were the commonest presentations. Computed tomography of the chest was the commonest mode of diagnosis (68%), although 7 cases required repeat testing. Overall mortality was 55%, with significantly reduced mortality in patients undergoing surgical repair (33%) compared with endoscopic treatment (65%) and conservative management (97%) (adjusted odds ratio, 24.9; P<0.01, compared with surgery). Multivariable predictors of mortality include presentation with neurological symptoms (adjusted odds ratio, 16.0; P<0.001) and gastrointestinal bleed (adjusted odds ratio, 4.2; P=0.047).

CONCLUSIONS

AEF complicating atrial fibrillation ablation is associated with a high mortality. Clinicians should have a high suspicion for the development of AEF in patients presenting with infective, neurological, gastrointestinal, or cardiac symptoms within 2 months of an atrial fibrillation ablation. Investigation by contrast computed tomography of the chest with consideration of repeat testing can lead to prompt diagnosis. Surgical intervention is associated with improved survival rates.

How to prevent, recognize and manage complications of AF ablation?

Ablation of atrial fibrillation (AF) is one of most complex procedures in electrophysiology. Many technical improvements have been incorporated lately in order to improve clinical results and reducing risks. Currently, cardiac tamponade, stroke, PV stenosis, phrenic palsy and atrial esophageal fistula are still recognized as the major risks of AF ablation, although their managements have been much better established. The aim of this article is to review recent data in how to avoid, to identify and to treat such complications.

Upper gastrointestinal complications following ablation therapy for atrial fibrillation

BACKGROUND

Following ablation therapy for cardiac arrhythmias, patients may develop upper gastrointestinal (UGI) symptoms. The vagus nerve is close to the atria and may be affected by ablating energy.

AIM

To identify structural or functional complications in UGI tract following ablation for atrial fibrillation (AF) and clinical outcomes and association with vagal dysfunction.

METHODS

Using natural language processing of electronic medical records and an AF ablation database of 5380 patients treated during 17 years, we identified 40 patients with UGI complications. We evaluated vagal dysfunction by electrocardiogram (ECG) showing lack of sinus arrhythmia (variation in R-R interval by ≥120 milliseconds, in presence of normal sinus P waves and constant P-R interval).

KEY RESULTS

Among 40 patients: (A) eight had structural GI complications confirmed by diagnostic tests: seven with esophageal ulcer/erosions and no signs of UGI bleeding and one developed esophagopericardial fistula (and survived with treatment); (B) 15 had functional UGI complications confirmed by objective motility tests. Nine had newly developed symptoms and six had aggravated symptoms; and (C) the remaining 17 had GI symptoms without relevant diagnostic results. Most UGI issues resolved spontaneously or with conservative treatment. However, 2 died several weeks after ablation procedure; cause of death was suspected atrioesophageal fistula or esophageal rupture. Vagal dysfunction persisted for 3 months in 13 and was transient in 8.

CONCLUSIONS/INFERENCES

Although most GI issues resolved spontaneously, there should be a high index of clinical suspicion in patients with persistent symptoms. Vagal dysfunction may serve as a marker of more extensive tissue damage.

Atrioesophageal Fistula After Atrial Fibrillation Ablation: A single center series

Background

The incidence of atrioesophageal fistula (AEF) after atrial fibrillation catheter ablation is reported to be 0.015%-0.04%, though it is likely underreported due to a number of factors including misdiagnosis. We report our institutional experience with AEF.

Methods

Patients with confirmed diagnosis of AEF between 2004 and 2016 at our institution were identified (n=5) and their clinical characteristics and outcome were analyzed.

Results

AEF occurred in 5 patients who underwent AF catheter ablation (3 ablated at our institution; 2 transferred from outside hospitals after diagnosis of AEF). Symptoms were chest pain (n=3), fever (n=3), TIA/stroke (n=3), dysphagia (n=1), and headache (n=1). Chest pain was the earliest symptom and occurred 21-24 days post-RFA. One patient had sudden death without preceding symptoms. Findings included leukocytosis (WBC count range of 17200-19,000) and sepsis. Chest CT was obtained in 3 patients and showed air in the left atrium or mediastinum. Three patients had evidence of multifocal stroke on MRI. Three patients died before surgery could be performed. Two patients (40%) underwent emergent surgery which included partial excision of atrial wall, closure with bovine pericardial patch and closure of esophageal lesion. Surgical outcomes were favorable (100% survival).

Conclusion

Chest pain and fever were the early symptoms of AEF and occurred before the neurologic complications. Chest CT was an excellent tool for detection of AEF. All patients who were diagnosed correctly and underwent surgery survived. Early detection is imperative as prompt surgery may improve survival. Health-care community education is the key to ensure early detection and transfer to a qualified surgical center.

Atrial-oesophageal fistula following percutaneous radiofrequency catheter ablation of atrial fibrillation: the risk still persists

Aims

Atrial-oesophageal fistula is a serious complication related to ablation of atrial fibrillation. As its occurrence is rare, there is a great lack of information about their mechanisms, incidence, presentations, and treatment. The objective of this manuscript is to present a series of cases of atrial-oesophageal fistula in Brazil, focusing on incidence, clinical presentation, and follow-up.

Methods and results

This is a retrospective multicentre registry of atrial-oesophageal fistula cases that occurred in eight Brazilian centres from 2003 to 2015. Ten cases (0.113%) of atrial-oesophageal fistula were reported in 8863 ablation procedures in the period. Most of the subjects were male (70%) with age 59.6 ± 9.3 years. Eight centres were reference units in atrial fibrillation ablation with an experience over than 200 procedures at the time of fistula occurrence. Oesophageal temperature monitoring was performed in eight cases using coated sensors in six. The first atrial-oesophageal fistula clinical manifestation was typically fever (in six patients), with a median onset time of 16.5 (12–43) days after ablation. There was a delay of 7.8 ± 3.3 days between the first manifestation and the diagnosis in five patients. The treatment was surgical in six cases, clinical in three and stenting in one. Seven patients died (70%) and two developed permanent neurological sequelae.

Conclusion

Atrial-oesophageal fistula remains a serious complication following AF ablation despite the incorporation of protective measures and increased technical experience of the groups. The high morbidity and mortality despite the treatment indicates the need to develop adequate preventive strategies.

Atrio-Esophageal Fistula: A Case Series and Literature Review

Case series

Patient: Male, 72 • Male, 29 • Male, 75

Final Diagnosis: Atrio-esophageal fistula

Symptoms: Altered mental state • chest pain • fever • melena

Medication: —

Clinical Procedure: —

Specialty: Critical Care Medicine