The heart is a complex organ that pumps blood throughout the body. It sits in the chest, slightly left of center, behind the breastbone, and between the lungs. A heart that is not healthy does not ...

The heart has four chambers that contract and relax in a specific rhythm to oxygenate blood and pump it throughout the body. The heart’s electrical system coordinates muscle contractions to maintain a ...

As the central part of the circulatory system, the heart is responsible for pumping blood, supplying oxygen and nutrients, and removing metabolic waste such as carbon dioxide from all the tissues in ...