How does angiotensin II increase the workload of the heart after a myocardial infarction (MI)?
A)By increasing the peripheral vasoconstriction
B)By causing dysrhythmias as a result of hyperkalemia
C)By reducing the contractility of the myocardium
D)By stimulating the sympathetic nervous system

Question

Quizplus · Accepted Answer

Angiotensin II is released during myocardial ischemia and contributes to the pathogenesis of a myocardial infarction (MI) in several ways, including causing peripheral vasoconstriction and fluid retention. These homeostatic responses increase myocardial work and thus exacerbate the effects of the loss of myocyte contractility. Angiotensin II does not cause hyperkalemia and dysrhythmias; it does not reduce cardiac contractility, and it does not stimulate the SNS.

How Does Angiotensin II Increase the Workload of the Heart