What are the coronary arteries?
Coronary arteries supply blood to the heart muscle. Like all other tissues
in the body, the heart muscle needs oxygen-rich blood to function, and
oxygen-depleted blood must be carried away. The coronary arteries run
along the outside of the heart and have small branches that supply blood
to the heart muscle.
What are the different coronary arteries?
The 2 main coronary arteries are the left main and right coronary arteries.
Right coronary artery (RCA). The right coronary artery supplies blood to the right ventricle, the right
atrium, and the SA (sinoatrial) and AV (atrioventricular) nodes, which
regulate the heart rhythm. The right coronary artery divides into smaller
branches, including the right posterior descending artery and the acute
Additional smaller branches of the coronary arteries include the obtuse
marginal (OM), septal perforator (SP), and diagonals.
Why are the coronary arteries important?
Since coronary arteries deliver blood to the heart muscle, any coronary
artery disorder or disease can reduce the flow of oxygen and nutrients
to the heart, which may lead to a heart attack and possibly death. Atherosclerosis
is inflammation and a buildup of plaque in the inner lining of an artery
causing it to narrow or become blocked. It is the most common cause of
What is coronary artery disease?
Coronary heart disease, or coronary artery disease (CAD), is characterized
by inflammation and the buildup of and fatty deposits along the innermost
layer of the coronary arteries. The fatty deposits may develop in childhood
and continue to thicken and enlarge throughout the life span. This thickening,
called atherosclerosis, narrows the arteries and can decrease or block
the flow of blood to the heart.
The American Heart Association estimates that over 16 million Americans
suffer from coronary artery disease--the number one killer of both men
and women in the U.S.
What are the risk factors for coronary artery disease?
Risk factors for CAD often include:
High LDL cholesterol, high triglycerides levels, and low HDL cholesterol
High blood pressure (hypertension)
High saturated fat diet
Controlling risk factors is the key to preventing illness and death from CAD.
What are the symptoms of coronary artery disease?
The symptoms of coronary heart disease will depend on the severity of the
disease. Some people with CAD have no symptoms, some have episodes of
mild chest pain or angina, and some have more severe chest pain.
If too little oxygenated blood reaches the heart, a person will experience
chest pain called angina. When the blood supply is completely cut off,
the result is a heart attack, and the heart muscle begins to die. Some
people may have a heart attack and never recognize the symptoms. This
is called a "silent" heart attack.
Symptoms of coronary artery disease include:
Heaviness, tightness, pressure, or pain in the chest behind the breastbone
Pain spreading to the arms, shoulders, jaw, neck, or back
Shortness of breath
Weakness and fatigue
How is coronary artery disease diagnosed?
In addition to a complete medical history and physical exam, tests for
coronary artery disease may include the following:
Electrocardiogram (ECG or EKG). This test records the electrical activity of the heart, shows abnormal
rhythms (arrhythmias), and detects heart muscle damage.
Stress test (also called treadmill or exercise ECG). This test is given while you walk on a treadmill to monitor the heart
during exercise. Breathing and blood pressure rates are also monitored.
A stress test may be used to detect coronary artery disease, or to determine
safe levels of exercise after a heart attack or heart surgery. This can
also be done while resting using special medicines that can synthetically
place stress on the heart.
Cardiac catheterization. With this procedure, a wire is passed into the coronary arteries of the
heart and X-rays are taken after a contrast agent is injected into an
artery. It's done to locate the narrowing, blockages, and other problems.
Nuclear scanning. Radioactive material is injected into a vein and then is observed using
a camera as it is taken up by the heart muscle. This indicates the healthy
and damaged areas of the heart.
Treatment for coronary heart disease
Treatment may include:
Modification of risk factors. Risk factors that you can change include smoking, high cholesterol levels,
high blood glucose levels, lack of exercise, poor dietary habits, being
overweight, and high blood pressure.
Medicines. Medicine that may be used to treat coronary artery disease include:
Antiplatelets. These decrease blood clotting. Aspirin, clopidogrel, ticlopidine, and prasugrel
are examples of antiplatelets.
Antihyperlipidemics. These lower lipids (fats) in the blood, particularly low density lipid
(LDL) cholesterol. Statins are a group of cholesterol-lowering medicines,
and include simvastatin, atorvastatin, and pravastatin, among others.
Bile acid sequestrants--colesevelam, cholestyramine and colestipol--and
nicotinic acid (niacin) are other medicines used to reduce cholesterol levels.
Antihypertensives. These lower blood pressure. Several different groups of medicines work
in different ways to lower blood pressure.
Coronary angioplasty. With this procedure, a balloon is used to create a bigger opening in the
vessel to increase blood flow. Although angioplasty is done in other blood
vessels elsewhere in the body, percutaneous coronary intervention (PCI)
refers to angioplasty in the coronary arteries to permit more blood flow
into the heart. PCI is also called percutaneous transluminal coronary
angioplasty (PTCA). There are several types of PCI procedures, including:
Balloon angioplasty. A small balloon is inflated inside the blocked artery to open the blocked area.
Coronary artery stent. A tiny mesh coil is expanded inside the blocked artery to open the blocked
area and is left in place to keep the artery open.
Atherectomy. The blocked area inside the artery is cut away by a tiny device on the
end of a catheter.
Laser angioplasty. A laser used to "vaporize" the blockage in the artery.
Coronary artery bypass. Most commonly referred to as simply "bypass surgery" or CABG
(pronounced "cabbage"), this surgery is often done in people
who have chest pain (angina) and coronary artery disease. During the surgery,
a bypass is created by grafting a piece of a vein above and below the
blocked area of a coronary artery, enabling blood to flow around the blockage.
Veins are usually taken from the leg, but arteries from the chest or arm
may also be used to create a bypass graft. Sometimes, multiple bypasses
may be needed to fully restore blood flow to all regions of the heart.