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About the Heart

Home > Medical Group Services > Cardiology > About the Heart

The heart is a muscular, hollow organ that constantly pumps blood throughout the body.

The heart is made up of four chambers. There are two chambers on the left side, and two chambers on the right. The upper chamber on each side, called the atrium, receives and collects blood. The lower chamber on each side, called a ventricle, pumps blood.

Four valves direct the flow of blood within the heart. They act like one-way doors, allowing blood to move in only one direction.

The four chambers work together to contract and pump blood. As it circulates, blood delivers oxygen and nutrients throughout the body.

In order to keep pumping day after day, the heart needs its own supply of oxygen. The coronary arteries are the vessels that carry oxygen-rich blood to the heart muscle.

As blood leaves the left ventricle, it is pumped into the aorta, the body’s main artery. At the beginning of the aorta, near the top of the heart, two coronary arteries emerge. They are referred to as the “left” and “right” coronary arteries. These two arteries and their branches are what carry oxygen rich blood to the heart.