An aortoesophageal fistula (AEF) is an abnormal connection between the aorta and the esophagus. It is a rare but extremely severe condition that often requires urgent medical intervention. During the 9th China Vascular Conference (CVC 2024) held in Chengdu from September 12-14, Professor Worawong Slisatkorn from the Department of Cardiothoracic Surgery at Siriraj Hospital, Thailand, shared his valuable experience in treating AEF.
Clinical Presentation and Diagnosis of AEF
The clinical manifestations of AEF can be identified using the Chiari Triad, which includes three main symptoms: central chest pain, sentinel bleeding, and massive hemorrhage. In diagnosing AEF, computed tomography (CT) and esophagoscopy are commonly used methods. Esophagogastroduodenoscopy (EGD) is particularly useful for revealing characteristic signs such as visible grafts, bleeding, adherent clots, ulcers, or pulsatile masses.
AEF can be categorized into primary and secondary types. Primary AEF is typically caused by thoracic aortic aneurysms, foreign body ingestion, postoperative complications, or esophageal malignancies. Secondary AEF, on the other hand, often occurs after thoracic aortic endovascular repair (TEVAR) or open thoracic aortic aneurysm repair.
Treatment strategies for AEF include conservative management, aortic repair, and esophageal repair. Aortic repair may involve TEVAR or open surgery, such as in-situ graft replacement, omental flap fixation, or extra-anatomical bypass. Esophageal repair may include esophageal stent placement, esophageal repair, or, in severe cases, esophagectomy. The choice of treatment should be customized based on the patient’s specific condition and the nature of the fistula.
Single-Center Experience from Siriraj Hospital
From 2006 to 2022, Siriraj Hospital in Thailand treated 18 patients with AEF, with an average age of 65 years, of whom 72% were male. Among these cases:
•Primary AEF: 7 cases (39%), with most (86%) caused by thoracic aortic aneurysms and a few (14%) by esophageal cancer.
•Secondary AEF: 11 cases (61%), with most (73%) related to TEVAR and the remaining (27%) related to open surgery.
The overall survival rate of AEF patients was 50%:
•Primary AEF Survival Rate: 57%. Among patients undergoing open surgery, the survival rate was 75%, with 100% survival for those undergoing esophagectomy, and 50% for those undergoing repair. The survival rate for patients treated with TEVAR was 33%, and 33% of TEVAR cases were converted to open surgery.
•Secondary AEF Survival Rate: 45.5%. The survival rate for patients undergoing open surgery was 71%, with 75% for those undergoing esophagectomy and 50% for those undergoing repair. There were no survivors among the patients treated with TEVAR, and 66% of TEVAR cases eventually converted to open surgery.
These data reflect Siriraj Hospital’s clinical experience and treatment outcomes in managing AEF.
European Registry Study: Incidence and Treatment Strategies for AEF Post-TEVAR
According to data from a European registry study published in the European Journal of Cardiothoracic Surgery , the incidence of AEF after TEVAR is 1.5%, with most patients being male (75%) and having a median age of 69 years. The majority of cases occurred 3 months post-TEVAR, with a median stent coverage length of 17 cm and a median oversizing of 15%. The main clinical manifestations were fever of unknown origin (FUO, 81%), hematemesis (53%), and shock (22%). For diagnosis, CT was widely used (92%), while endoscopy was used less frequently (50%).
Among 36 patients divided into four treatment groups based on strategy, the 1-year survival rates were as follows:
•Conservative treatment (10 patients, 28%): 0% survival rate.
•Esophageal stent placement only (6 patients, 17%): 17% survival rate.
•Esophagectomy only (7 patients, 19%): 43% survival rate.
•Esophagectomy with aortic replacement (13 patients, 36%): 46% survival rate.
These data highlight the correlation between aggressive surgical strategies and improved 1-year survival rates.
Optimal Surgical Strategies for AEF
From October 1999 to May 2017, Kobe University Hospital treated 27 patients with AEF to explore optimal surgical strategies for improving patient outcomes. The results showed that aggressive surgical strategies could provide better treatment outcomes for AEF patients. For hemodynamically stable patients, concurrent surgery may yield better outcomes. For hemodynamically unstable patients, TEVAR may serve as a bridging treatment before open surgery. The study also noted the possibility of esophageal reconstruction in survivors after treatment. The surgical methods are summarized below:
1.Left Thoracotomy: Suitable for patients with lesions mainly in the descending aorta and relatively stable hemodynamics. This surgery allows simultaneous resection of the aortic arch, descending aorta, and esophagus, using a rifampicin-soaked Dacron graft for in-situ reconstruction and an omental flap for graft protection.
2.Median Sternotomy: Suitable for aortic arch aneurysms, particularly in patients with severe chronic obstructive pulmonary disease (COPD) or after right lung resection. Procedures include aortic arch replacement, esophagectomy, and omental flap fixation.
3.TEVAR as an Initial Bridging Surgery: For hemodynamically unstable patients, TEVAR can be used as an initial bridging surgery to stabilize the patient’s condition before proceeding to open surgery.
Summary
AEF is a rare but potentially fatal condition. The key to AEF treatment is addressing both the aorta and the esophagus. For surgical candidates, concurrent open aortic surgery combined with esophagectomy or esophageal repair is the best treatment option. For patients unsuitable for open surgery, TEVAR can be used as a bridging strategy in emergency situations.
