Mitral aneurysm: a rare complication of subaortic diaphragm infective endocarditis

Abstract

Mitral valve aneurysm is a rare and uncommon complication of infective endocarditis leading to a weakened mitral tissue. The most feared mitral valve aneurysm's complications are: perforation and severe mitral regurgitation. Multiple mechanisms have been suggested to explain the development of mitral valve aneurysm in aortic infective endocarditis including: local extension of the infection, the mitral kissing vegetation and aortic regurgitation. We report the case of a 29-year-old man who had infective endocarditis of a native aortic valve and the sub-aortic diaphragm complicated by a perforated mitral valve aneurysm diagnosed only by transesophageal echocardiogram. The patient had no sign of heart failure. We hypothesized that all those mechanisms lead to the developing of the mitral valve aneurysm in this case, but also the presence of the diaphragm favored the spread of the infection.