Final answer:
Hypoplastic left heart syndrome (HLHS) is a congenital heart defect characterized by underdevelopment of the left side of the heart. It involves abnormalities in the left atrium, left ventricle, and the aorta. The pulmonary arteries may also be affected.
Step-by-step explanation:
Hypoplastic left heart syndrome (HLHS) is a congenital heart defect characterized by underdevelopment or hypoplasia of the left side of the heart. The anatomic features of HLHS involve abnormalities in the left atrium, left ventricle, and the aorta.
In HLHS, the left atrium and the two auricles may be reduced in size. The primitive heart tube, which forms from the fusion of two endocardial tubes, may not develop properly, resulting in a malformed left ventricle.
The aorta may be very small or entirely absent in HLHS, and the pulmonary arteries may also be affected. The pulmonary arteries are the branches of the pulmonary trunk that carry deoxygenated blood from the heart to each of the lungs. In HLHS, these arteries may be narrowed or malformed, further complicating the condition.