CV Response To Exercise

Question 1

Describe the CV response to exercise

Answer 1

CO increases in proportion of Vo2 required

Stroke volume
Preload, contractility

Heart rate
SNS via epinephrine and norepinephrine and
Higher brain, proprioceptors, chemoreceptors, baroceptors
Hormonal
Ions/ chemicals

Blood pressure
As SV increases the force exerted on the vessel walls will proportionally increasing blood pressure. Generally there is steady rise in systolic blood pressure and diastolic pressure is maintained.

Note: a decrease in a systolic pressure could be caused by the vasodilation of large vessel during exercise for example the legs.

A decrease in diastolic pressure could be caused by a more forceful systolic contraction requiring a longer period of relaxation

Question 2

Discuss two pathologies that may affect a patients response to exercise

Answer 2

MI
An area of image of ischemic tissue will be replaced by non contractile scar tissue. This does not have the ability to respond to the increase in contraction following preload via the frank starling law.

PVD
This may reduce perfusion at the working muscles causing intermittent claudication causing the patient to stop exercise due to pain.