Cardiovascular involvement is not well studied in children with sickle cell disease. The aim of this study was to evaluate the echocardiographic parameters of children with sickle cell disease. We performed a transversal and case-control study including 80 subjects of six months to 16 years of age divided into four groups of 20 children each: heterozygous sickle cell disease, homozygous sickle cell anemia, anemia of other causes than sickle cell, and healthy children. All children had a complete physical examination, biological screening including hemogram and hemoglobin electrophoresis, chest x-ray, electrocardiogram, and Doppler echocardiogram. Data were compared using the chi 2 method and the Student's t-test. The mean age was 8.5 years and the sex-ratio was 1. Echocardiographic abnormalities were observed in seven patients with anemia unrelated to sickle cell, 15 children with heterozygous anemia and all the homozygous patients. The main abnormalities were: left ventricular enlargement (ten homozygous patients, one heterozygous subject, five of the patients with another cause of anemia), increased contractility of the heart (18 homozygous patients, seven heterozygous patients, five in the anemia group) and mild to moderate mitral or tricuspid regurgitation (12 homozygous, five heterozygous and five patients in the anemia group). One homozygous child had a dilated and hypokinetic cardiomyopathy with pulmonary hypertension. The parameters of left ventricular systolic function and left heart chamber dimensions were lower in the control group (P < 0.04). This study shows the frequency of heart chamber dilatation with left ventricular hyperkinesis usually described in the literature. The lack of case of chronic cor pulmonale may be due to the young age of our patients. One case of dilated and hypokinetic cardiomyopathy suggests that other causes than anemia should be considered, particularly myocardial ischemia, which could not be demonstrated because of our limited investigative methods. These results emphasize the frequency of the heart involvement in sickle cell disease, particularly in the homozygous type, and point out the importance of the cardiologic screening of these patients.