ABSTRACT
The case of a six year old girl with a congenital aortic stenosis is presented. A few months before being admitted to the Instituto Nacional de Cardiologia; her clinical manifestations suggested a bacterial endocarditis. The existance of an aneurismatic area in the ascending aorta and the later development of a crisis of angor pectoris, suggested a mycotic aneurism of the ascending aorta as a possible diagnosis; and the dissection or migration of septic material to the aneurism was found, it has a sacular form of 3.5 by 3.8 cm in the ascending aorta. There was also dissection into the left coronary artery at the ostium level. Microscopic study showed areas of recent myocardial necrosis on the free wall of the left ventricle and in the lower part of the interventricular septum. The etiopathogeny, clinical manifesations, radiology, evolution and treatment of mycotic aneurism were considered. The need of an early clinical diagnosis and early medical and surgical treatment is emphasized.
