The aortic valve separates the lower left chamber (left ventricle) of the heart and the aorta, the large artery that carries blood from the heart to the rest of the body.

The aortic valve works like a one-way gate, opening so that blood from the left ventricle—the heart's main pump—can be pushed into the aorta. When the heart rests between beats, the aortic valve closes to keep blood from flowing backward into the heart.