Aortoesophageal fistula

Aortoesophageal fistula is a rare fistulous communication between the aorta and oesophagus and results in life threatening upper gastrointestinal haemorrhage. It is fatal in the absence of prompt management. 

Epidemiology

Aortoesophageal fistula has an incidence of 0.5 to 1.7% ⁸.  Rupture of aortic aneurysm within the oesophagus is the most common cause and constitutes 54.2% of all cases ³. Other causes include ^1,2,4:

• atherosclerotic plaque

• foreign body 

• oesophageal cancer

• infections

• radiotherapy

• endovascular stent erosion

• aortic graft infection

Diagnosis

CT Angiography is used to diagnose aortoesophageal fistula although upper gastrointestinal endoscopy may be performed to rule out other possible causes of upper gastrointestinal haemorrhage ^2,3. 

Clinical presentation 

The patient usually presents as a case of emergency with massive haemorrhage and haematemesis. Clinical presentation is classically described by the Chiari triad consisting of ^3,5:

• mid Thoracic pain 

• sentinel haemorrhage 

• exsanguination following a symptom free period (seen in 80% of the patients)

Pathology

The etiopathogenesis of aortoesophageal fistula is only known in certain cases. Continuous arterial pulsations and resultant trauma is cited as a cause for the development of aortoesophageal fistula in patients with aortic stents ⁷. Rupture of an abscess following infection also leads to formation of aortoesophageal fistulas in some cases ⁷.

Radiographic features

CT angiography in an aortoesophageal fistula may show ^1,8: 

• extravasation of contrast material 

• gas effusion

• oesophageal narrowing

• false aneurysm 

• mediastinal haematoma 

• teat like outpouching from aorta into oesophagus 

• stent migration 

• mural thrombus

Treatment and prognosis 

Aortoesophageal fistula has a mortality rate of 77% and requires urgent management ³. 

Haematemesis is managed with the Sengstaken-Blakemore tube, which temporarily stabilises the patient with its tamponade effect ^1,3. 

Management of aortoesophageal fistula involves two steps: aortic repair and oesophageal repair. Aortic repair is usually performed by a minimally invasive procedure called thoracic endovascular aortic repair. Oesophageal repair involves oesophagectomy and oesophageal stent placement ^1,3. 

Surgical management can also be done by open surgery, which has a higher mortality rate but allows a thorough management of infection in the presence of an infectious cause ³. 

Differential diagnosis

Aortoesophageal fistula needs to be differentiated from other causes of upper gastrointestinal haemorrhage. 

History and etymology 

Aortoesophageal fistula was first described in 1818 by a French naval surgeon Dubreiul ⁶. 

See also 

Aortoenteric fistula