One step thoracotomy approach for atrial- esophageal stula repair without cardiopulmonary bypass

Atrial-esophageal fistula is an extremely rare disease and a life-threatening complication after catheter ablation for atrial fibrillation. There is no consensus on the management or repair for atrial-esophageal fistula which has a high mortality rate. Here, we describe a lateral thoracotomy approach focused on simplifying the repair procedure for atrial-esophageal fistula in two patients.


Introduction
Catheter ablation for atrial brillation (AF) is widely utilized and considered safe with 6% of complications [1]. Although atrial-esophageal stula (AEF) is an uncommon disease, it is a lifethreatening complication after catheter ablation for AF [2,3]. The onset of AEF occurs several days to 2 months after catheter ablation. Its symptoms are diverse, including neurologic changes [2]. Because of its rarity, there is no agreed gold standard for repairing AEF which has a high mortality rate up to 80% [4].
Herein, we illustrate a lateral thoracotomy approach focusing on a simple repair for AEF with two cases.

Case 1
A 61-year-old man presented to the emergency department with a history of 3 days of fever. He has a background of catheter ablation using radiofrequency energy for AF one month ago, end stage renal disease requiring hemodialysis, and pace maker insertion. After admission to the hospital for evaluation of fever, his mental decrease was noted. Brain magnetic resonance imaging (MRI) showed multifocal embolic infarct. Streptococcus salivarrius and Streptococcus mitis/oralis were cultured in blood. A repeated chest computed tomography (CT) demonstrated AEF (Fig. 1A).
Surgical strategy was urgently planned. After endotracheal general anesthesia, the patient was placed in the right down decubitus position. Single lung ventilation was initiated. A thoracotomy was performed on the left 5th intercostal space. After left lung retraction, pericardium was opened, revealing severe adhesion. Access to the stula through pericardial space was attempted, but was abandoned due to excessive adhesion. Attention was then turned to outside the pericardium. After opening mediastinal pleura on left hilum, the stula site was founded along the esophagus (Fig. 1E). We con rmed the 3 mm stula with esophageal traction cautiously. From posterior pericardial re ection, three times of pledgeted 4 − 0 prolene sutures for ligation were paced on the stula of the pericardial side gently. Fistula ligation and resection were performed, followed by an additional primary repair for esophageal defect. The repair procedure was nished with massive irrigation and chest drain tube insertion.
Postoperatively, the patient was treated for sequelae of an initial stroke and pneumonia. After one week without oral nutrition, we con rmed a well-repaired stula site without residual lesion on endoscopy (Fig.   1B). He was discharged on postoperative day 31 with a tracheal tube.

Case 2
A 70-year-old man had radiofrequency catheter ablation for AF. Fifty days following the procedure, he was admitted with cognitive decline. Multiple cerebral infarct lesions were found on brain MRI. Blood cultures for fever revealed multiple Streptococcus spp. A CT scan of the chest was suggestive of an AEF (Fig. 1C).
Surgery was urgently performed. Surgical approach was the same as case 1. Through left thoracotomy on the 5th intercostal space, inspection of the pericardial space showed calci ed adhesion. Through mediastinal space, esophagus was exposed and pulled gently. The 3 mm stula on posterior aspect of the paricardium was isolated and ligated with several pledgeted 4 − 0 prolene sutures carefully. After stulectomy, primary esophageal repair was done. With massive irrigation, a chest tube was then inserted. The wound was closed in a layered fashion.
The patient's postoperative course was focused on respiratory care with tracheostomy and rehabilitation for sequelae of cerebral infarction. Endoscopy revealed no speci c ndings after one week of fasting period (Fig. 1D). He was discharged on postoperative day 23 with a tracheal tube.

Discussion
Early diagnosis and surgical intervention are important in AEF. There are several treatment options for AEF, including esophageal stenting, intra-cardiac repair, extra-cardiac repair, and esophageal repair [2,3,5,6].
Intra-cardiac repair of AEF needs sternotomy and cardiopulmonary bypass. Two-stage approach using intra-cardiac repair and esophageal repair has several disadvantages. It not only needs a cardiopulmonary bypass, but also needs position change of the patient [7]. Another hybrid technique [8] including intra-cardiac repair and an endoscopic clipping has a risk for possibility of failure of the clipping procedure and the need for thoracic operation in case of re sulization.
Cases with single step repairs of AEF using thoracotomy approach with or without cardiopulmonary bypass have also been reported [9,10]. Our cases had a treatment strategy similar to the method reported by Khandhar et al. [10]. However, we did not use intercostal muscle aps or any stapler devices.
The single step of lateral thoracotomy for AEF has several advantages in patients who are judged to be free of left atrial active bleeding to the pericardial space. This lateral thoracotomy method can reduce operating time and eliminate the need for a cardiopulmonary bypass and a surgical position change. An AEF can be visually and reliably removed in one step. Even if the problem on the left atrium side remains, there is a room for further approach by open heart surgery. Like our two cases who are less likely to have active bleeding of the left atrial wall, we can check intra thoracic nding rst and solve the stula lesion.
Even in those with multiple cerebral infarcts, it becomes burdensome to use cardiopulmonary bypass worrying about cerebral hemorrhagic change.

Conclusion
We encountered two AEF cases which are quite rare. Long-term follow-up data between surgical approaches for AEF are lacking. Our experience suggests that one step repair for AEF via lateral thoracotomy might be feasible in selected patients, especially in those with concomitant cerebral infarct.