Between left ventricle and aorta; includes noncoronary (posterior semilunar),
right coronary (semilunar) and left coronary (semilunar) cusps
Opens during systole; blood is ejected from left ventricle into aorta.
Closes during diastole; prevents reflux from aorta into left ventricle.
Importance in cardiovascular diseases:
Aortic stenosis (genetic or acquired), aortic regurgitation.
Importance in device delivery:
Artificial valves - bioprosthetic (xenograft, homograft) and mechanical.