Increased Afterload (E.g.,hypertension)

Question

Increased afterload (e.g.,hypertension)
A) is usually caused by arteriolar dilation.
B) increases the work of the heart.
C) can only occur when preload increases.
D) is usually caused by intense parasympathetic (vagal) discharge.

Accepted Answer

Afterload refers to the amount of resistance the heart must overcome to eject blood from the left ventricle, and an increase in afterload (such as with hypertension) means there is more resistance. This increases the work the heart must do to overcome the resistance and eject blood, leading to increased oxygen demand and potential damage to the heart over time. Arteriolar constriction (not dilation) can contribute to increased afterload, and preload (the amount of blood that fills the heart before each beat) is separate from afterload. Parasympathetic discharge would decrease heart rate and decrease contractility, which would reduce afterload, not increase it.