lifestyle impact on CV system

Question 1

different types of stress

Answer 1

Exercise (duration minutes to hours) – Training (months/years)

Hypothermia/hyperthermia (duration hours/days)

Anabolic steroids use (months)

Sustained High sympathetic NS activity i.e. drugs/battlefield (duration months/years)

Sustained periods of high sugar intake (years/decades)

Question 2

total peripheral resistance

Answer 2

If TPR decreases (e.g. in exercise) then CO must increase to maintain arterial pressure and therefore perfusion of essential organs.

Question 3

cellular mechanisms in response to stress: pathological

Answer 3

Pathological hypertrophy generates a larger (hypertrophic) myocardium.
But this myocardium:
Contracts poorly.
Is more prone to arrhythmias and ventricular fibrillation.

Question 4

cellular mechanisms in response to stress: physiological

Answer 4

Physiological hypertrophy generates a larger (hypertrophic) myocardium.
This myocardium:
Contracts normally.
Is not prone to arrhythmias and ventricular fibrillation.
NB larger atria may be more prone to AF