Magnetic resonance angiography in the evaluation of aortic pseudoaneurysm

Ascending aorta pseudoaneurysm simulating mediastinal lymphoma in computed tomography, a possible diagnostic error: a case report

Background

An ascending aortic pseudoaneurysm is a severe and rare complication following cardiothoracic surgery. This case report demonstrates its possible misinterpretation and the consequent importance of multidisciplinary evaluation.

Case presentation

We present a case of an 18-year-old Caucasian man with Marfan syndrome who developed an ascending aortic pseudoaneurysm about 1 year after undergoing cardiac surgery with the Bentall procedure. Computed tomographic examination of the thoracic aorta and positron emission tomography–computed tomography initially suggested a lymphomatous pathology. However, these imaging results were in contrast to the transesophageal echocardiogram and the laboratory data that showed negative results for hematological pathology. A second computed tomographic scan redirected the diagnosis toward a pseudoaneurysm.

Conclusion

This case demonstrates the utility of close communication and interdisciplinary consultation between cardiovascular radiologists and the cardiac surgery team, which are mandatory in order to maximize their diagnostic skills in identifying postoperative complications.

Pseudoaneurysms of the ascending aorta following coronary artery bypass surgery

BACKGROUND

Ascending aortic pseudoaneurysms following prior cardiac procedures are a rare entity. We reviewed our institutional experience given the isolated case reports in the literature.

METHODS

A 10-year retrospective review identified 5 patients who underwent ascending aorta pseudoaneurysm repair. There were 3 women and 2 men with a median age of 70 years (range 63 to 79 years). Median duration from initial CABG to pseudoaneurysm repair was 5 years (range 5 months to 18 years). The clinical presentations included dyspnoea (2 patients), chest pain, fever of unknown origin, and a pulsatile mass. Four patients underwent urgent investigation and surgery. Diagnosis was established via CT scan (3 patients), transesophageal echocardiogram (1 patient), and MRA (1 patient). Two patients had a prior history of sternal wound infection.

RESULTS

Mortality was 60%. One survivor experienced a stroke. The etiology was prior cannulation site in 4 cases and vein graft anastamotic site in 1. Necrotic aortic tissue was noticed in 2 cases. Aortic tissue cultures were negative in all the patients. Cardiopulmonary bypass was established prior to sternotomy in 4 cases and 1 case was performed off-pump. Inadvertent rupture of the pseudoaneurysm (without exsanguination) occurred in 2 cases following sternotomy. Repair was performed with bovine pericardial patch in 2 cases and plication in 3 cases.

CONCLUSION

This highlights the varied presentation, necessity for urgent diagnosis and repair with a high operative mortality due to the late presentation. Aggressive diagnosis should be sought and consideration should be given to catheter-based interventions for initial treatment.