MCQ – 74440

Best index to measure cardiac afterload is:

A.	Mean arterial pressure
B.	LV end diastolic pressure
C.	LV mean systolic pressure
D.	Total peripheral resistance

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Correct Answer � D Explanation

Ans: D. Total peripheral resistance

(Ref: Ganong 25Ie p544, 24/e p546)

• Cardiac output depends on both preload & afterload.
• The preload is defined by the venous return & left ventricular end-diastolic volume while the afterload is defined by the mean arterial pressure, which then fitrther depends on total peripheral resistance.