Aortic regurgitation in the heart is caused by deformation, thickening, calcification, and restriction of movement of the aortic valve leaflets, resulting in inadequate closure of the valve and flow of the ejected blood back to the left ventricle. Aortic regurgitation causes a reduction in effective beat volume and is called aortic valve insufficiency, which is mostly combined with varying degrees of aortic stenosis. The most common cause of aortic valve insufficiency is rheumatic heart valve disease. In addition, bacterial endocarditis, Marfan syndrome, congenital aortic valve malformation, and aortic coarctation aneurysm are also common clinical causes of aortic valve insufficiency.