CO = SV × HR
Cardiac output = CO (mL/minute or liters/minute)
Stroke volume = SV (mL/beat)
Heart rate = HR (beat/minute)
resting cardiac output differs among individuals of different size
cardiac output is often expressed as a flow (L/min) per body surface area (m2) and is called cardiac index (L/min/m2)
Cardiac index normally ranges from 2.6 to 4.2 L/min/m2.