|Events of cardiac cycle|
|Atrial systole||Atria contract and small amount of blood enters ventricles. AV valves are opened and semi lunar valves are closed. Duration is 0.11 secs.|
|Isometric contraction||All the valves are closed. Pressure in ventricles is raised. Duration is 0.05 secs.|
|Ejection period||Semilunar valves are opened. Ventricles contract and blood is ejected into aorta and pulmonary artery. This period lasts for 0.22 secs.|
|Proto diastole||Semilunar valves are closed. Duration of this period is 0.04 secs.|
|Isometric relaxation||All the valves are closed and pressure in the ventricles is reduced. Duration is 0.06 secs.|
|Rapid and slow filling||AV valves are opened. Ventricles relax and filling occurs. Duration is 0.3 secs.|
Duration of cardiac cycle is 0.8 secs.
Duration of systole is 0.3 secs and diastole is 0.5 secs.
[Sembulingam 4th ed 493/ 5th ed 515]