The aortic valve is one of four heart valves that help control the flow of blood through the heart. The aortic valve controls the blood flow of oxygenated blood from the left ventricle into the rest of the body. The valve's other job is to prevent blood from flowing backwards into the heart. However, if the aortic valve doesn't work properly, aortic valve regurgitation may occur. That is when the valves don't close properly and some of the blood leaks back into the heart. Another problem that can occur is aortic valve stenosis. This is when the valve has narrowed and cannot open completely. Find out more about the aortic valve and various treatments.