Afterload is readily broken into components; aortic pressure and/or the pressure the ventricle must overcome to eject blood.

Afterload is largely dependent upon aortic pressure.

Since aortic pressure is higher than pulmonary pressure, a continuous murmur occurs.

Studies have shown the importance of central aortic pressure and its implications in assessing the efficacy of antihypertensive treatment with respect to cardiovascular risk factors.

This results in the slight increase in aortic pressure caused by the elastic recoil of the semilunar valves and aorta.

Since pressure is also lower than the aortic pressure, the aortic valve is closed as well.

At point B, pressure becomes higher than the aortic pressure and the aortic valve opens, initiating ejection.

At the end of this phase, pressure lowers again and falls below aortic pressure.

When the pressure in the left ventricle decreases, the aortic pressure forces the aortic valve to close.

Elevated afterload (commonly measured as the aortic pressure during systole) reduces stroke volume.