A clinical consideration of systemic embolism complicated to infective endocarditis in Korea

Infective endocarditis is still one of the important fatal diseases in Korea, especially when systemic embolisms are supervene. So, identification of patients who are in the high risk of embolism and who can be helped by early surgical intervention is very important. Considering these, we tried to elaborate the risk factors for the systemic embolism in patients with an infective endocarditis and the influence of systemic embolism on the mortality and morbidity in patients with an infective endocarditis.

We retrospectively reviewed the clinical records of 97 patients who were admitted with the infective endocarditis between January 1983 and October 1993.

Among 97 patients, 80 patients met our diagnostic criteria. The mean age of patients was 38 years old. There were 43 males and 37 females. The mean duration of fever since the fever developed by history was 38 days. Valvular heart disease was the most frequent underlying heart disease. Mitral regurgitation and aortic regurgitation were the most common among valvular heart diseases. Pneumonia and acute pharyngotonsillitis were the most frequent predisposing factors of infective endocarditis. Blood cultures were positive in 51 patients (63.8%). Streptococcus viridans was the organism isolated most frequently, and Staphylococcus aureus was the second most frequently isolated one. Vegetations were detected in 58 patients (76.3%) by an echocardiography. Mitral valve and aortic valve were the most frequently involved incidence rate of embolism was 50% and the most frequent embolism site was the central nervous system and extremities were the next. Embolism occurred at the mean of 37 days after onset of fever. Overall in-hospital mortality rate was 26.3% and a cardiac-origin was the major cause of death. The only statistically significant risk factor for mortality was systemic embolism. The analysis of the relation between an incidence of embolism and the multivariables (age, presence of vegetation, location of vegetation, size of vegetation, causative organisms) showed that only the growth of Staphylococcus aureus had a significant trend toward a risk of subsequent systemic embolism.

This study suggests that systemic emboli increases the mortality rate in patients with infective endocarditis. Age of patients, presence of vegetation, size and location of vegetation are not the risk factors for embolism, while certain organism, especially Staphylococcus aureus, could be a risk factor for the systemic embolism.