[Cardiac abscess in infectious endocarditis. Apropos of 25 anatomo-clinical cases].

Although rarely suspected clinically, cardiac abscesses are a serious and not uncommon complication of infective endocarditis (IE). Twenty-five cardiac abscesses were found at autopsy in 125 cases of IE on native valves. The anatomoclinical features of these cases are described. Cardiac abscesses usually occur in patients with previous valvular heart disease (21/25) and more commonly in aortic valve endocarditis (15/25) especially when complicating calcific aortic stenosis (9/25). The predominant infecting organism was staphylococcus aureus (9 cases). An iatrogenic portal on entry was confirmed in 9/25 cases. Conduction defects (14/25) commonly led on to sudden death (9 cases) despite attempts at temporary pacing (14/25) commonly led on to sudden death (9 cases) despite attempts at temporary pacing (2 cases%. The clinical history was shorter than 2 months in 4/5 cases. The average age of the patients was 53.3 years. The commonest site of infection was the aortic valve (16/25), affecting the posterior cusp in all cases. It is difficult to summarise the localisation of the abscesses as collection of pus extended in all directions. Involvement of the valve rings (aortic 10 cases--mitral 5 cas), of the interventricular septum (15 cases), of the LV free wall (17 cases), was common, sometimes in association, and fistula formation between two different cavities was observed in 4 cases. The abscess may communicate with a cardiac chamber or remain enclosed in the parietal structures (17 cas) reaching an average size of 2 cm diameter. Histological examination distinguished collected forms with an identifiable pyogenic membrane from the extensive, gangrenous, necrotic form with detectable microbial colonies in 9 cases.(ABSTRACT TRUNCATED AT 250 WORDS)