Rapid formation of pseudoaneurysm of the mitral-aortic intervalvular fibrosa in a patient with bicuspid aortic valve and infective endocarditis: a case report.

backgroundPseudoaneurysm of the mitral-aortic intervalvular fibrosa (P-MAIVF) is a rare yet severe cardiac pathology that typically arises as a complication of infective endocarditis or cardiac surgery. This condition is associated with a high mortality rate, particularly in instances where timely surgical intervention is not conducted. Transesophageal echocardiography (TEE) is the preferred diagnostic modality, offering detailed visualization of the pathological communication between the pseudoaneurysm and the left ventricular outflow tract, along with its dynamic changes throughout the cardiac cycle. CASE PRESENTATION: A 28-year-old Han Chinese woman with a congenital bicuspid aortic valve (BAV) presented with recurrent fever suggestive of infective endocarditis (IE). Cardiac ultrasound revealed vegetations on the aortic valve along with a mitral-aortic intervalvular fibrosa pseudoaneurysm. Contrast-enhanced chest CT demonstrated a pseudoaneurysm communicating with the left ventricular outflow tract. The patient subsequently underwent aortic valve replacement and repair of the mitral-aortic fibrous connection under extracorporeal circulation. The patient recovered successfully with an uneventful postoperative course.

conclusionThis case underscores that congenital BAV is a significant predisposing factor for the rapid development of P-MAIVF in the setting of infective endocarditis. TEE is the diagnostic modality of choice for characterizing the lesion and its hemodynamic consequences. Early recognition and timely surgical intervention are crucial to prevent catastrophic rupture and ensure favorable outcomes.