A heart cycle corresponds to one heartbeat. During the cycle, the left and right sides of the heart are synchronized. When the cardiac muscle (myocardium) relaxes, the blood carried by the veins fills the heart cavities (atriums and ventricles). When the myocardium contracts, the blood is forced out of the heart into the arteries.
A visualization in three phases of the cardiac cycle.
Check the heart cycle rhythm (normal or slow motion) that you want to observe.