After reporting a clinical case of a patient with a Staphylococcus Aureus Acute Endocarditis involving the aortic valve being complicated with cardiac failure irresponsive to medical treatment, which required a surgical procedure, the authors describe the preoperative echocardiography features. These features have the particularity of identifying a pseudoaneurysm rising in the outflow tract of the left ventricle, that involves the annulus and the anterior mitral leaflet, opening into the left atrium. They also take the opportunity to review the main local complications of Infective Endocarditis, affecting native or prosthetic valves, and make some comments on the diagnostic echocardiographic possibilities.