What is the most common congenital heart defect found in patients with Down syndrome?

The most common congenital heart defect associated with Down syndrome is the complete atrioventricular septal defect (AVSD). This condition occurs due to the failure of proper development of the atrial and ventricular septa, leading to a single common atrioventricular valve instead of separate mitral and tricuspid valves. The presence of AVSD is particularly common in individuals with Down syndrome due to the chromosomal abnormalities affecting cardiac development.

Children with complete AVSD tend to have significant hemodynamic changes, leading to heart failure and pulmonary hypertension if not corrected. The association of AVSD with Down syndrome highlights the need for systematic cardiac evaluation in patients with this genetic condition, as early diagnosis and intervention can dramatically improve outcomes.

Other defects such as ventricular septal defects (VSD) and atrial septal defects (ASD) are indeed found in congenital heart disease, but they do not have the same prevalence linked with Down syndrome as complete AVSD. Coarctation of the aorta also occurs in patients with various congenital heart defects but is not specifically associated with Down syndrome to the same extent as complete AVSD. Thus, the recognition of complete atrioventricular septal defect in patients with Down syndrome is essential for both their management and