These widenings are between the wall of the aorta and each of the three cusps of the aortic valve.

[2] The aortic sinuses cause eddies which prevent the valve cusps from touching the internal surface of the aorta and obstructing the openings of the coronary arteries.

These give rise to coronary arteries:[4][better source needed] The aortic sinuses are typically more prominent than the pulmonary sinuses.

[5] If the coronary arteries arise from the wrong aortic sinuses, this can put the heart's ventricles at risk of ischaemia.

[6] This is often only discovered when a heart attack has already occurred, usually before the age of 20 and during exercise.