Within a physiologic range,an increase in left ventricular end-diastolic volume (preload)leads to a(n):
A) increased force of contraction.
B) decrease in refractory time.
C) increase in afterload.
D) increase in repolarization.

Question

Quizplus · Accepted Answer

An increase in left ventricular end-diastolic volume (preload) leads to stretching of the myocardium, which is one of the factors regulating the force of contraction. This is known as the Frank-Starling mechanism, which states that the greater the stretch, the greater the force of contraction. Therefore, an increase in preload leads to an increased force of contraction.

Within a Physiologic Range,an Increase in Left Ventricular End-Diastolic Volume