Cardiac cycle

Definition

The cardiac cycle is the sequence of events that occurs in the heart during one complete heartbeat, encompassing both the contraction (systole) and relaxation (diastole) of both atria and ventricles. It ensures blood is pumped effectively throughout the body.

Related terms

Systole: The phase of the heartbeat when the heart muscle contracts and pumps blood from the chambers into the arteries.

Diastole:

The phase of the heartbeat when the heart muscle relaxes and allows the chambers to fill with blood.

Stroke Volume:

The amount of blood ejected by a ventricle of the heart during a single contraction