Coronary heart disease
Your heart is a pump that circulates blood to your lungs and the rest of your body. The surface of your heart is covered with blood vessels called coronary arteries, which supply your heart muscle with blood.
Coronary heart disease happens when fatty deposits build up on the walls of your coronary arteries. This is known as atherosclerosis.
In atherosclerosis, fat and cholesterol in your blood builds up on your artery walls, forming a plaque or atheroma. The plaque can prevent your heart muscle from getting the blood supply it needs. Because of the reduced blood flow and the rough edges of the plaque, a blood clot sometimes forms, blocking your artery.
Sometimes the plaque may rupture, which also causes your blood to clot. This is called atherothrombosis. Atherothrombosis stops an area of your heart muscle receiving blood and oxygen, leading to a heart attack. If a lot of your heart muscle is damaged, your heart may stop beating regularly. Sometimes the damage causes your heart to stop beating altogether, which is fatal.