Systolic Ejection sounds occur shortly after the first heart sound, at the time of ventricular ejection.  Normally, the opening of the aortic or pulmonic valves and the onset of ventricular ejection is not audible. In certain cardiac conditions extra sounds are heard shortly after the first heart sound, S1.   They are produced by the opening of the aortic or pulmonic valves, either when one of these valves is diseased (valvular) or when ejection is rapid through a normal valve (vascular).

Aortic ejection sounds of valvular origin are heard in patients with coarctation of the aorta usually associated with congenital bicuspid aortic valve, valvular aortic stenosis, aortic insufficiency, or aneurysm of the ascending aorta. Valvular ejection sounds may be heard in clinical conditions associaated with forceful left ventricular ejection, such as thyrotoxicosis, anemia, pregnancy, exercise, high cardiac output states.
Aortic ES is loudest at aortic area and cardiac apex with no respiratory variations.

Pulmonic ejection sounds are associated with dilatation of the main pulmonary artery, including pulmonary hypertension and valvular pulmonary stenosis. Pulmonary ES is best heart at pulmonic area and decreases coincident with inspiration.