In terms of cardiac cycle phases, what happens during systole?

During systole, the primary event that occurs is the contraction of the ventricles. This phase of the cardiac cycle is crucial for the efficient pumping of blood from the heart into the arteries. As the ventricles contract, they create pressure that forces blood out of the right ventricle into the pulmonary artery and out of the left ventricle into the aorta, delivering oxygen-rich blood throughout the body and facilitating the circulation of blood necessary for various physiological functions.

The contraction of the ventricles is initiated by electrical impulses generated by the sinoatrial node and transmitted through the cardiac conduction system, leading to increased intraventricular pressure. This pressure rise is what propels the blood into the respective arteries. Systole is typically followed by diastole, where the chambers of the heart fill with blood again in preparation for the next cycle. Understanding this phase is essential, as it plays a critical role in determining cardiac output and overall cardiovascular health.