Idiopathic Pseudoaneurysm of the Mitral–Aortic Intervalvular Fibrosa

The mitral–aortic intervalvular fibrosa is an avascular fibrous structure between the anterior mitral leaflet and the aortic annulus. Pseudoaneurysm formation of the mitral–aortic intervalvular fibrosa is a rare but known entity most commonly caused by infective endocarditis or valve surgery. We present a 29-year-old patient with a mitral–aortic intervalvular fibrosa pseudoaneurysm of no evident cause who was successfully managed surgically.