Regression of coronary aneurysms in patients with Kawasaki syndrome.

Coronary aneurysms were demonstrated echocardiographically in 34 of 186 patients who presented with Kawasaki syndrome between 1979 and 1983. The aneurysms were confirmed by selective coronary angiography in 27 patients and by postmortem examination in one. The 27 surviving patients with proven aneurysms were followed for 2 to 40 months (mean 15), during which they received low dose (5 to 10 mg/kg) aspirin daily. Progressive improvement and resolution of aneurysms were observed by serial echocardiography in 18 patients and confirmed by angiography in 14. Coronary aneurysms persisted, however, in nine other patients for 14 to 40 months (mean 25.7). The incidence of aneurysm resolution was higher in children less than 1 year of age at the onset of the illness than in patients older than 1 year (100% vs 50%; p less than .001). Aneurysms were more likely to resolve in girls than in boys (100% vs 42%; p less than .001). Fusiform aneurysms tended to resolve more frequently than saccular lesions (80% vs 18%; p less than .025). Aneurysms located distally in the coronary arteries appear to regress more rapidly than proximal ones. We conclude that an age of less than 1 year at the onset of Kawasaki syndrome, female sex, and fusiform aneurysm morphology are significant factors that favor resolution of coronary artery aneurysms. However, important questions remain with regard to the long-term fate and functional capabilities of these healed lesions.