Spontaneous healing of a ruptured mycotic aneurysm of the posterior mitral leaflet: Unexpected resolution of a severe mitral regurgitation.

Mycotic mitral valve aneurysm is an uncommon complication that rarely appears in isolated mitral valve endocarditis. The weakened aneurysmal wall may rupture, causing severe mitral regurgitation. In this situation surgery is essential. We present a case of a rare complicated mycotic posterior mitral aneurysm. After completing the antibiotic course for Streptococcus agalactiae infective endocarditis, an unexpected healing process within the aneurysm led to the virtual disappearance of the mitral regurgitation and remarkably changed the patient's clinical outcome. We emphasize the key role of three-dimensional transesophageal echocardiography, as it is becoming the reference imaging technique for infective endocarditis.