Heart disease

To better understand a heart condition, you must first understand how the heart works and how common heart conditions, such as coronary artery disease, atrial fibrillation and congestive heart failure, occur.

How it works

The heart is a pump made of muscle tissue. Like any muscle, it needs a constant supply of oxygen and nutrients, which are carried to the heart by the blood through the coronary arteries.

After circulating through the body, oxygen-poor blood returns to the heart through the right atrium. This chamber empties blood into the right ventricle. As the right ventricle contracts, it pumps blood into the lungs, where it receives fresh oxygen.

The oxygen-enriched blood enters the left atrium, where it collects until it is pushed into the left ventricle, the main pumping chamber of the heart. The left ventricle pumps the blood through the aorta and into the circulatory system, where it is distributed to the entire body.

To do its work, the heart muscle needs its own set of blood vessels (coronary arteries) to provide oxygen and nutrients.