Cardiac Cycle Overview

Study Notes

Cardiac Cycle Overview

The cardiac cycle is the series of events that occur during one heartbeat. It involves two main phases: diastole and systole. During these stages, the heart contracts and relaxes, pumping blood through the body's circulatory system. This process is crucial for maintaining various bodily functions such as tissue respiration and temperature regulation.

Diastole Phase

During this phase, the heart chambers fill with blood from the atria, which is then directed into the ventricles. The septum, a muscular wall separating the right and left sides of the heart, prevents mixing between oxygenated and deoxygenated blood.

Atrial Contraction

Atrial contraction, also known as atrial systole, occurs when the walls of the atria contract and push blood into the ventricles. This phase allows for efficient filling of the ventricles.

Systole Phase

In contrast to diastole, during systole, the heart contracts. The right side pumps oxygen-poor blood to the lungs while the left side pushes oxygen-rich blood out to the rest of the body.

Ventricular Contraction

Ventricular contraction, commonly referred to as ventricular systole, is when the ventricle muscles contract forcefully to expel blood from the heart. This action propels blood throughout the body via arteries.

Preparations for Next Heartbeat

Once the heart has completed its primary role—pumping blood around the body—it begins preparing for the next beat. Both atria and ventricles begin their relaxation processes, allowing them to refill with blood once more.

Despite being less discussed compared to other physiological processes like breathing and eating, understanding the cardiac cycle is critical for comprehending how our bodies function effectively.

Description

Learn about the cardiac cycle, which comprises diastole and systole phases where the heart contracts and relaxes to pump blood through the body. Understand the importance of atrial and ventricular contractions in maintaining circulation and overall bodily functions.