Which of the following does NOT directly affect stroke volume of the left ventricle?

Question

Quizplus · Accepted Answer

Parasympathetic stimulation does not directly affect stroke volume of the left ventricle. Rather, it primarily affects heart rate (slowing it down). The other choices all play a role in regulating stroke volume. The degree of stretch of the ventricles (A) affects the force of contraction, and the Frank-Starling law (B) describes the relationship between ventricular stretching and stroke volume. The amount of blood in the ventricle prior to contraction (C) affects the end-diastolic volume, a determinant of stroke volume. Finally, the pressure needed to open the aortic valve (E) affects the ejection of blood from the left ventricle into the aorta, and therefore stroke volume.

Which of the Following Does NOT Directly Affect Stroke Volume