Coloured axial computed tomography (CT) scan through the aortic valve of a 48 year old with aortic valve insufficiency. This is a heart valve disease where the aortic valve can no longer control the flow of blood from the left ventricle into the aorta. The scan shows a leak of the aortic valve, measuring the size of an isosceles triangle with a 1cm side (in diastolic phase). Aortic valve insufficiency can be treated by aortic valve replacement or valve repair.