In transposition of the great vessels, which arrangement describes the great arteries?

• A. Aorta arises from the right ventricle and the pulmonary arteries arise from the left ventricle
• B. Aorta arises from the left ventricle and the pulmonary arteries arise from the right ventricle
• C. Vessels cross each other
• D. Ventricles are in normal arrangement

Answer: (A)

Transposition of the great arteries is defined by the great arteries arising from the opposite ventricles, creating two parallel circulations instead of the normal series flow. The arrangement where the aorta arises from the right ventricle and the pulmonary arteries arise from the left ventricle matches this swapped configuration exactly. In a normal heart, the aorta comes from the left ventricle and the pulmonary artery from the right ventricle, so that description would not reflect TGA. Descriptions that merely say the vessels cross or that ventricles are in normal arrangement don’t specify the crucial arterial origins, which is what defines transposition.