Aneurysm of the Anterior Mitral Valve Complicating Infectious Mitro-Aortic Endocarditis in a Biscuspid Aortic Valve: About a Case

Mitral valve aneurysm is a rare condition usually associated with aortic valve endocarditis. The mechanism, poorly understood, generally includes a regurgitant infectious flow originating from the aortic valve, direct contact with vegetation and direct propagation, through adjacent structures, such as the mitro-aortic intervalvular fibrous body. This report details the case of a 56-year-old patient followed for severe bicuspid aortic insufficiency of the aortic valve for 4 months and admitted to heart failure due to infectious endocarditis with a fatal outcome. Physical examination revealed aortic and mitral insufficiency syndrome and congestive heart failure. Transthoracic echocardiography revealed type 1 L-R bicuspid heart disease and leaking polyvalvulopathy with severe eccentric aortic and severe mitral regurgitation. The aortic and mitral valves were the seat of the vegetations. The mitral valve was the seat on its atrial side of a contained aneurysmal sac with thrombosed hyperechogenicity. Blood cultures were positive for streptococci and probabilistic dual antibiotic therapy was started. The patient was unable to benefit from surgical treatment. However, the patient died following complications such as ischemic stroke and septic shock. A necropsy was not done.