Adult Echocardiography Practice Exam

Endocardial cushion defects, also known as atrioventricular septal defects, are significant congenital heart defects that result from the failure of the endocardial cushions to develop properly during fetal development. These defects are characterized by a combination of atrial septal defect and ventricular septal defect, along with a common atrioventricular valve.

These defects are notably prevalent in individuals with Down's syndrome (trisomy 21). This genetic condition is associated with a range of congenital anomalies, including cardiac defects. The presence of endocardial cushion defects in Down's syndrome patients is attributed to the chromosomal abnormalities affecting the development of cardiac structures during embryogenesis.

Other conditions listed, while they may have associated cardiac anomalies, do not share the same strong correlation with endocardial cushion defects as Down's syndrome does. For instance, Marfan's syndrome is mainly associated with aortic dilation and mitral valve prolapse but not typically with endocardial cushion defects. Acromegaly is caused by excess growth hormone and is more related to other systemic effects rather than specific congenital heart defects. Fitz-Hugh Curtis syndrome is an inflammatory condition linked to pelvic inflammatory disease and does not involve congenital heart anomalies.

Hence, the high occurrence of endocardial