The aortic orifice connects the aorta with the left ventricle. It is occupied by the aortic semilunar valve. This has a dovetail structure. It is equipped with semi-lunar valvular flaps (shaped, of course, of half-moon):
- left and right anterior semilunar flaps called coronary semilunars (as there are the orifices of coronary artery origin).
- posterior semilunar flap
The three flaps present, at the free margin, that is, the one facing the orifice lumen, a fibrous thickening called Aranzio's nodule whose function is to guarantee a better closure of the valve.
The contraction and relaxation of the valve are mediated by blood pressure and papillary muscles, as is the case for the tricuspid valve.