An interesting case of an aortopulmonary artery fistula

A Case of Aortopulmonary Fistula with Post-Operative Aortic Pseudoaneurysm Diagnosed by Transesophageal Echocardiography

Tracheobronchial or esophageal fistula after aortic surgery has been reported sporadically in the literature, however, reports of an aortopulmonary fistula associated with a post-operative aortic pseudoaneurysm are rare. We experienced a case of refractory heart failure due to an aortopulmonary fistula associated with a post-operative aortic pseudoaneurysm. A 60-year-old man who had undergone aortic surgery 2 years earlier was hospitalized for congestive heart failure. He was diagnosed with refractory heart failure after 10 days of diuretic therapy failed to improve his condition. He underwent a contrast-enhanced computed tomography (CT) scan and was suspected to have pulmonary artery perforation of an aortic pseudoaneurysm at the anastomotic site of the ascending aortic surgery. Transesophageal echocardiography showed shunt blood flow from the aortic aneurysm into the right pulmonary artery, leading to a definitive diagnosis of aortopulmonary fistula with post-operative aortic pseudoaneurysm. Computed tomography angiography is commonly used to diagnose an aortic fistula; however, diagnosis is often difficult because of the subtle imaging findings. We highlight the usefulness of transesophageal echocardiography in providing a definitive diagnosis and detailed morphologic information on this pathophysiology.

Acquired aortopulmonary fistula: a case report

Background

Aortopulmonary fistula is a rare complication of ascending aorta pathology. Presentation is most commonly dramatic with acute onset chest pain or heart failure secondary to left to right shunting. We describe a patient with acquired aortopulmonary fistula who had an insidious onset of heart failure as his presenting complaint. We also highlight the utility of multimodality cardiac imaging in establishing the diagnosis.

Case summary

A 79-year-old male patient with a history of coronary artery bypass graft surgery and mechanical aortic valve replacement, 23 years prior, presented with exertional dyspnoea of 7 months duration. An initial workup that included transthoracic and transoesophageal echocardiography as well as coronary and bypass graft angiography failed to diagnose an acquired aortopulmonary fistula complicating an ascending aortic pseudoaneurysm. Upon referral to our institution, the correct diagnosis was suspected on off-axis transthoracic echocardiography. The fistula was subsequently confirmed, and the extent of ascending aorta pathology defined via a multimodality imaging approach that consisted of transoesophageal echocardiography and cardiac computed tomography. The patient underwent successful surgical repair and was discharged in a stable condition.

Discussion

Acquired aortopulmonary fistula is a rare clinical entity. We describe a patient who had an insidious presentation of heart failure and found to have a large ascending aortic aneurysm that eroded into the main pulmonary artery creating a fistulous communication. The diagnosis was delayed and required a high index of suspicion and multimodality cardiac imaging.