The Heart
Explore the four chambers, valves, major vessels, and external anatomy of the organ that powers circulation.
The heart as a double pump
The heart is a muscular organ with four chambers. Its right side receives oxygen-poor blood and pumps it toward the lungs, while its left side receives oxygen-rich blood and pumps it toward the systemic circulation.
Interactive external heart anatomy
Rotate the model to inspect the external surface and the major vessels attached to the heart.
Four chambers
The two atria receive blood, while the two ventricles pump blood out of the heart. The right and left sides are separated by the septum.
The internal anatomy of the heart
A labeled cross-sectional diagram makes the chambers, valves, and great vessels easier to identify.
Receives systemic blood
Receives oxygen-poor blood returning from the body through the systemic veins.
Pumps to the lungs
Sends blood through the pulmonary circulation toward the lungs.
Receives pulmonary blood
Receives oxygen-rich blood returning from the lungs.
Pumps to the body
Sends oxygen-rich blood into the systemic circulation.
Why valves matter
Heart valves help maintain one-way blood flow through the chambers. They open and close in response to pressure differences as the heart contracts and relaxes.
The heart is two pumps working at the same time.
The right side sends blood to the lungs. The left side sends blood to the rest of the body.