Diastolic pressure is the lowest pressure in the arteries before ventricular contraction
Preload is the amount the ventricle stretch at the end of diastole
The more muscle fibers are stretched, the greater the contraction force 
The maximum pressure when ventricles contract is systolic pressure
Afterload is the pressure that the heart must work against to eject blood during systole (ventricular contraction)
Force of contraction increases when arterial pressure is below normal
Heart rate increases when arterial pressure is below normal
Vasodilation happens when pressure is above normal
