Question

Vasoconstriction is a response to decreased cardiac output. What does this result in?

A) Increased afterload
B) Decreased preload
C) Vasodilation
D) Increased cardiac output

Answer 1

Vasoconstriction, in response to decreased cardiac output, results in an increased afterload due to the greater resistance against which the heart has to pump blood.

Step-by-step explanation:

Vasoconstriction is the narrowing of blood vessels resulting from contraction of the vascular smooth muscle. In response to decreased cardiac output, vasoconstriction occurs to help increase blood pressure and improve blood flow back to the heart. One consequence of vasoconstriction is an increase in afterload, which is the tension the ventricles must overcome to pump blood out of the heart. An increased afterload is due to the greater resistance that the contracting heart must work against when the blood vessels are narrowed. Therefore, the correct answer to the question is A) Increased afterload.