Diagram :- Stages of one cardiac cycle

Cardiac cycle

Stages of cardiac cycle :- There are three stages 

1. Atrial systole :- Contractions of atria ( 0.1 seconds ) 

2. Ventricular systole :- Contraction of ventricles ( 0.3 seconds ) 

3. Complete Cardiac cycle :- relaxation of the atria and ventricles ( 0.4 seconds )

The total period of 1 cycle = 0.8 seconds