Coronary artery disease, also called coronary heart disease, or simply, heart disease, is the No. 1 killer in America, affecting more than 13 million Americans.
Heart disease is a result of plaque buildup in your arteries, which blocks blood flow and heightens the risk for heart attack and stroke.
What Is Coronary Artery Disease?
Heart disease is a result of plaque buildup in your coronary arteries -- a condition called atherosclerosis -- that leads to blockages. The arteries, which start out smooth and elastic, become narrow and rigid, restricting blood flow to the heart. The heart becomes starved of oxygen and the vital nutrients it needs to pump properly.
How Does Coronary Artery Disease Develop?
From a young age, cholesterol-laden plaque can start to deposit in the blood vessel walls. As you get older, the plaque burden builds up, inflaming the blood vessel walls and raising the risk of blood clots and heart attack. The plaques release chemicals that promote the process of healing but make the inner walls of the blood vessel sticky. Then, other substances, such as inflammatory cells, lipoproteins, and calcium that travel in your bloodstream start sticking to the inside of the vessel walls.
Eventually, a narrowed coronary artery may develop new blood vessels that go around the blockage to get blood to the heart. However, during times of increased exertion or stress, the new arteries may not be able to supply enough oxygen-rich blood to the heart muscle.
In some cases, a blood clot may totally block the blood supply to the heart muscle, causing heart attack. If a blood vessel to the brain is blocked, usually from a blood clot, an ischemic stroke can result. If a blood vessel within the brain bursts, most likely as a result of uncontrolled hypertension (high blood pressure), a hemorrhagic stroke can result.
What Is Ischemia?
Cardiac ischemia occurs when plaque and fatty matter narrow the inside of an artery to a point where it cannot supply enough oxygen-rich blood to meet your heart's needs. Heart attack can occur - with or without chest pain and other symptoms.
Ischemia is most commonly experienced during:
Exercise or exertion
Excitement or stress
Exposure to cold
Coronary artery disease can progress to a point where ischemia occurs even at rest. And ichemia can occur without any warning signs in anyone with heart disease, although it is more common in people with diabetes.