Final answer:
Aortic regurgitation is a condition where the aortic valve does not close properly, leading to a backward flow of blood from the aorta into the left ventricle.
Step-by-step explanation:
Aortic regurgitation is a condition where the aortic valve does not close properly, resulting in a backward flow of blood from the aorta into the left ventricle. This occurs when one of the cusps of the valve is forced backward by the force of the blood, causing the closure mechanism to fail. The disruption to the normal flow of blood produces a heart murmur that can be detected using a stethoscope.