Which of the Following is Most Likely to Increase Stroke

Question

Which of the following is most likely to increase stroke volume?
A) A (+) inotropic drug
B) A vagolytic drug
C) A (-) chronotropic drug
D) A beta1-adrenergic blocker

Accepted Answer

A (+) inotropic drug increases the strength of cardiac muscle contractions, leading to an increase in stroke volume (the amount of blood ejected by the heart with each beat). Vagolytic drugs block the action of the parasympathetic nervous system, which can increase heart rate but not necessarily stroke volume. (-) Chronotropic drugs decrease heart rate but do not necessarily affect stroke volume. Beta1-adrenergic blockers block the action of epinephrine and norepinephrine on the heart, reducing both heart rate and contractility, which can lead to a decrease in stroke volume.