Congenital heart disease in children with Down's syndrome: Turkish experience of 13 years.

Background: Down's syndrome (DS) is the most common chromosomal abnormality due to a trisomy of chromosome 21 commonly associated with congenital heart defects (CHDs). This study aimed to evaluate the frequency and types of CHD patterns in Turkish children with DS.
Method: The data relate to paediatric patients with DS who underwent cardiologic screening between 1994 and 2007 and were reviewed in our Paediatric Cardiology unit.
Results: Four hundred and twenty-one out of the 1042 paediatric patients with DS studied over a 13-year period had associated CHD. Of these, 320 (77.6%) had a single cardiac lesion, while the remaining 92 patients (22.4%) had multiple defects. The most common single defect was an atrioventricular septal defect (AVSD) found in 141 patients (34.2%), followed by 69 patients (16.7%) showing secundum type atrial septal defect, and ventricular septal defect in 68 patients (16.5%). AVSDs were the leading type, isolated or combined with other cardiac anomalies with an overall occurrence of 19.8% of paediatric patients with DS, and 49.2% of paediatric patients with both DS and CHD.
Conclusion: This is the first study concerning the frequency and type of CHD observed in Turkish children with DS. The high frequency of AVSD in Turkish children with DS implied that early screening for CHDs by echocardiography is crucial. The correction of AVSDs in paediatric patients with DS should be performed in the first 6 months of life to avoid irreversible haemodynamic consequences of the defect.