Prosthetic valve endocarditis (PVE) due to Staphylococcus aureus is associated with high morbidity and mortality. Paravalvular abscess formation is a common complication of PVE at the aortic position, but fistula formation is rarely seen. This report describes an 84-year-old patient with staphylococcal aortic PVE. Although paravalvular involvement was diagnosed early, clinical features associated with high operative mortality precluded surgical treatment. Unexpectedly, abscess drainage with aorto-left atrial fistula formation led to the remission of fever and clinical stabilization. Moreover, the echocardiographic evolution of infective endocarditis is described, from the initial lesion (vegetation) through abscess formation to partial valve dehiscence, abscess drainage, and aorto-left atrial fistula formation, by means of transesophageal echocardiography.