The reasoning: MAP = CO × SVR; pulse pressure = SV ÷ compliance
- MAP ≈ DBP + ⅓(SBP − DBP) at resting heart rates (diastole is longer); MAP − RAP = CO × SVR.
- Systolic reflects SV, ejection velocity and arterial stiffness (plus wave reflection — earlier return of reflected waves in stiff arteries augments late systolic pressure).
- Diastolic reflects SVR, heart rate and elastic recoil (falls with stiffening and runoff, e.g. AR).
- Pulse pressure widens with larger SV (AR, exercise, hyperdynamic states) or reduced compliance (ageing → isolated systolic hypertension); narrows with low SV (shock, AS, tamponade).
- Pulse amplification: systolic pressure is higher in peripheral than central arteries in young people.