Multimodality imaging of tuberculous aortomitral intervalvular fibrosa aneurysm: A case report

The aortomitral intervalvular fibrosa (AMIVF) is a thin, avascular structure that lies between the anterior mitral leaflet and the non-coronary cusp of the aortic valve. It is particularly susceptible to infection and mechanical insult, making it a rare site for pseudoaneurysm formation. Among the various causes, tuberculosis is an exceedingly uncommon etiology, especially in immunocompromised patients. We report the case of a 27-year-old retroviral-positive male who presented with shortness of breath, palpitations, and hemoptysis. Initial echocardiography revealed a pseudoaneurysm at the aortomitral continuity with severe mitral and aortic regurgitation. Subsequent computed tomography (CT) aortogram confirmed the presence of a contrast-filled pseudoaneurysmal sac protruding into the left atrium. Cardiac magnetic resonance imaging (MRI) further delineated the anatomy, showing a cystic structure arising between the aortic and mitral valves, compressing the left atrium and confirming the diagnosis. The patient underwent surgical aneurysm resection and aortic valve replacement. Histopathology and cultures revealed Mycobacterium tuberculosis as the causative agent. Pseudoaneurysms of the AMIVF are rare but clinically significant. In immunocompromised individuals, tuberculosis should be considered a potential etiology. Multimodal imaging, including echocardiography, CT, and MRI, is crucial for timely and accurate diagnosis. Early surgical intervention is often required to prevent catastrophic complications such as rupture or fistula formation.