circulatory system library

The heart is a hollow, muscular organ that maintains blood circulation throughout the body. Learn how the circulatory system - your heart, blood vessels and blood - bring nutrients to the body.

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Cardiac Conduction System

Cardiac conduction is the process that causes the heart muscles to expand and contract rhythmically. This medical animation illustrates the process.

Cardiovascular System

The blood vessels and heart make up the cardiovascular system. This animation explains the component parts of blood and their functions in the body.

Coronary Artery Disease

Coronary artery disease can cause blockage to the coronary artery and can lead to a heart attack. This animation shows how it happens.

Irregular Heartbeat Waveforms

There are a number of different forms of irregular heartbeats. Click on the waveform text to see the waveform of different rhythms.

Nutrient Exchange

Nutrients and waste materials are carried by the red blood cells and distributed through diffusion at the capillaries. This animation shows how the process occurs.

Red Blood Cell Production

Blood is often referred to as the "river of life." Red blood cells transport oxygen to the body's tissues in exchange for carbon dioxide. This animation illustrates how red blood cells work.

Tachycardia

Tachycardia is the condition of a heart beating at more than 100 beats per second. This animation illustrates how the condition occurs inside the body.

The Heart

The heart is made up of four main chambers two ventricles and two atria. This animation illustrates the flow of blood through the heart to and from the four main vessels that connect to it.