In order to appreciate what has happened to your heart, you first need to know how the heart works.
The heart is a hollow, four-chamber organ that pumps blood through the arteries to feed all parts of the body. Blood contains the oxygen and nutrients needed by the body to function. Veins return blood containing carbon dioxide and other waste products back to the right side of the heart, where it is filtered by the lungs. The lungs then provide a new oxygen supply to the blood before it is recirculated.
The left side of the heart receives oxygen-rich blood from the lungs and pumps it out to the entire body through the aorta, or main artery. Inside your heart are four valves that open and shut with each heart beat. These valves keep blood moving in one direction.
Each heart beat originates from an electrical current within the heart. This electrical activity is automatic and stimulates the heart muscle to contract. View an image of the electrical system
The Coronary Arteries
Your heart needs oxygen and nutrition like any other muscle. The coronary arteries lie on the surface of the heart and provide fuel for the heart to work.
The right coronary artery supplies the bottom and back of the heart. The left coronary artery divides to serve the top, front, left side and back of the heart.