1. Nervous Control

Both heart rate and stroke volume are controlled by autonomic nerves.

Control of heart rate is achieved via pacemaker cells in the sino-atrial node. Factors which affect heart rate are said to have a chronotropic effect.

Control of stroke volume is achieved by controlling the force of contraction (contractility) of cardiac muscle cells particularly those in the ventricles. Factors which affect contractility are said to have an inotropic effect.