Afterload is best determined by?
High-Yield Explanation
Ans. c (Peripheral resistance). (Ref.; Gangong, Physiology, 22 nd/pg.p 572)PRE-LOAD AND AFTER-LOAD# After-load is the pressure in the arteries against which the ventricle pumps out the blood.- After-load = diastolic arterial pressure (proportional to peripheral resistance).- Vasodilators (e.g., hydralazine) decrease after-load.# The degree of filling of ventricles is pre-load.- Pre-load pumps up the heart.- Pre-load = ventricular end-diastolic volume- Venous dilators (e.g., nitroglycerin) decrease pre-load.- Pre-load increases with exercise (slightly) and with increase in the blood volume (overtransfusion) and excitement (sympathetics).