Hypoxia is said to have a negative inotropic effect on the heart, which means:

Question

A) The heart rate will slow down, so the atria and ventricles can fill better.
B) The cardiac output will decrease to cause less work for the heart.
C) The heart will adjust so that less time will be spent in diastole and filling of the ventricles will shorten.
D) There will be interference in the generation of ATP, which is needed for muscle contraction.

Answer 1

Ans: D
Feedback:
An inotropic influence is one that modifies the contractile state of the myocardium independent of the Frank-Starling mechanism. Hypoxia exerts a negative inotropic effect by interfering with the generation of ATP, which is needed for muscle contraction. Hypoxia does not directly slow the heart rate, decrease cardiac output, or interfere with filling times. However, these can develop if the ability of the muscle to contract becomes severe and is not treated promptly.