Abstract

Cardiac malformations in children with Down syndrome significantly contribute to morbidity and mortality, principally in the early years of life. Congenital heart diseases are characteristic and are a frequent cause of birth anomalies with an estimated prevalence of 4 to 5 per 1000 live births. The manifestations are primarily related to endocardial cushion defects, which may vary in severity. The most common defects are Atrioventricular Septal Defect (formally called Endocardial Cushion Defect), Ventricular Septal Defect, Persistent Ductus Arteriosus and Tetralogy of Fallot. These are of major concern in these children as they may lead to complications like failure to thrive, congestive heart failure, and pulmonary vascular disease. In addition, Down’s is also associated with ventricular septal defect (VSD), patent ductus arteriosus (PDA), and tetralogy of fallot (TOF). The management of these cardiac abnormalities remains crucial as survival beyond one year of age needs careful cardiology evaluation followed by prompt medical and surgical care. New insights into the genetics of this syndrome have improved our understanding of the pathogenetic mechanisms of cardiac defects. Recent changes in neonatal prevalence of Down syndrome suggest a growing number of children with cardiac malformations, in particular with simple types of defects. Ethnic and sex differences of the prevalence of specific types of congenital heart disease (CHD) have also been underlined. A recent study confirmed that subclinical morphologic anomalies are present in children with trisomy 21, also in the absence of cardiac defects, representing an internal stigma of Down syndrome. The results of cardiac surgery are significantly improved in terms of immediate and long-term outcomes, but specific treatments are indicated in relation to pulmonary hypertension. Particular aspects of the cardiovascular system have been described, clarifying a reduced sympathetic response to stress but also a 'protection' from atherosclerosis and arterial hypertension in these patients.