Kawasaki disease in young children with myocarditis and coronary artery vasculitis affecting the heart can have a significant impact on the child later in life. Once an arterial aneurysm or coronary artery calcification, occlusion or narrowing due to arteritis develops, it can affect the blood supply to the heart muscle and may usually induce myocardial infarction and cardiac dysfunction, which can affect the child’s future growth and development as well as survival. In the case of aneurysms, a rupture can be life-threatening. However, most children who do not have a heart attack have a better prognosis.