In humans, the heart is approximately the size of a closed fist and is located between the lungs, in the middle compartment of the chest, called the mediastinum. [4]

Heart, organ that serves as a pump to circulate the blood. It may be as simple as a straight tube, as in spiders and annelid worms, or as complex as the four-chambered double pump that is the center of the circulatory system in humans, other mammals, and birds.

Learn about the anatomy of the heart and how its chambers, valves, and vessels work together to maintain effective blood circulation throughout the body to sustain life.

Your heart is the main organ of your cardiovascular system, a network of blood vessels that pumps blood throughout your body.

This image shows the four chambers of the heart and the direction that blood flows through the heart. Oxygen-poor blood, shown in blue-purple, flows into the heart and is pumped out to the lungs.

How the Heart Works - What the Heart Looks Like | NHLBI, NIH

Knowing your heart location helps categorize your chest pain, but this is not the only clue. Learn how to tell if the pain is cardiac or non-cardiac in origin.

American Heart Association | To be a relentless force for a world of ...

The heart is an organ, about the size of a fist. The heart is made of muscle and pumps blood through the body. Blood is carried through the body in blood vessels called arteries and veins. The process of moving blood through the body is called circulation. Together, the heart and vessels make up the cardiovascular system.