[Infective endocarditis: a complication of idiopathic hypertrophic subaortic stenosis (author's transl)]

The idiopathic hypertrophic subaortic stenosis (IHSS) is thought to be infrequently complicated by infective endocarditis. Because IHSS is a disorder of the myocardium and not endocardium is not generally considered to have increased risk of infective endocarditis. Some Authors found, however, that approximately 5% of patients with IHSS develop bacterial endocarditis, because hemodynamically IHSS is like to valvular diseases. Therefore the incidence of endocarditis in IHSS is the same of valvular diseases. The vegetations can be found on anterior mitral valve leaflet, aortic cusps and subaortic endocardium. Some patients have dental surgery prior to the onset of endocarditis and others are infected with oral streptococci. For these reasons prophylactic antibiotics should be administered to patients with IHSS undergoing dental manipulation and in other settings where the risk of developing bacteremia is high. We describe one case of IHSS complicated with streptococcus viridans endocarditis. Vegetations, determined with echocardiography, were present on anterior mitral valve leaflet, aortic right coronary cusp and interventricular septum. In a review of literature we are been able to find twenty-seven cases of IHSS complicated with endocarditis.