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During cardiac examination of a newborn infant, a murmur is detected, and the diagnosis of patent ductus arteriosus is made. Which of the following best describes the direction of blood flow through the patent ductus arteriosus in this infant?
A. From aorta to left pulmonary artery
B. From aorta to left pulmonary vein
C. From aorta to right pulmonary artery
D. From left pulmonary artery to aorta
E. From right pulmonary artery to aorta


I know its from aorta to pulmonary artery (not sure about R or L) but i guess from aorta to R pulmonary art :oops:


I will choose A. :?:


The correct answer is A.

The ductus arteriosus connects the left pulmonary artery to the aortic arch. It is derived from the left sixth aortic arch.

During prenatal life, the pressure gradient causes blood to flow from the left pulmonary artery to the aorta. However, after birth, the pressure gradient reverses, and if the ductus arteriosus remains patent, the flow is from the aorta to the left pulmonary artery.

The ductus arteriosus does not connect to the pulmonary veins or the right pulmonary artery (choices B, C, and E).

The flow through the ductus arteriosus is from the left pulmonary artery to the aorta (choice D) prior to birth, but reverses after birth.

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