Coronary artery disease
What is coronary artery disease?
Coronary artery disease (CAD) is the accumulation of fatty deposits in the inner layer of the coronary arteries. The fatty deposits may begin to develop in childhood and they continue to thicken and enlarge during a person’s lifetime. This thickening, known as atherosclerosis, narrows the arteries and can decrease or block the flow of blood to the heart.
The American Heart Association estimates that more than 16 million Americans suffer from coronary artery disease — the No. 1 killer of both men and women in the U.S.
Coronary artery disease symptoms vary based on the severity of the disease. Some people with CAD have no symptoms, while others can experience mild to severe chest pain.
The chest pain, also called angina, is the result of too little oxygenated blood reaching your heart. When the blood supply is completely cut off, the result is a heart attack and the heart muscle begins to die. Some people can have a heart attack and never recognize the symptoms; this is called a "silent" heart attack.
When symptoms of coronary artery disease are present, they may include:
- Shortness of breath
- Weakness and fatigue
- Pain radiating in the arms, shoulders, jaw, neck and/or back
- Heaviness, tightness, pressure and/or pain in the chest behind the breastbone
Risk factors for CAD often include:
- Physical inactivity
- A diet high in saturated fats (found in many animal products, including meat and cheese)
- High blood pressure (hypertension)
- High and low LDL cholesterol, high triglyceride levels
Controlling risk factors is the key to preventing illness and death from CAD.
In addition to a complete medical history and physical examination, diagnostic procedures for coronary artery disease may include any, or a combination of, the following:
- An electrocardiogram (ECG or EKG)
This is a test that records the electrical activity of the heart, shows abnormal rhythms (arrhythmias or dysrhythmias), and detects heart muscle damage.
- A stress test (also called treadmill or exercise ECG)
This test is given while a patient walks 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, and/or to determine safe levels of exercise following a heart attack or heart surgery.
- Cardiac catheterization
With this procedure, X-rays are taken after a contrast agent is injected into an artery to locate the narrowing, occlusions and other abnormalities of specific arteries.
- Nuclear scanning
During this procedure, radioactive material is injected into a vein and observed using a camera as it is taken up by the heart muscle. This indicates the healthy and damaged areas of the heart.
Specific treatment will be determined by your doctor based on:
- Extent of the disease
- Your opinion or preference
- Expectations for the course of the disease
- Your age, overall health, and medical history
- Your tolerance for specific medications, procedures or therapies
Treatment may include:
- Modification of risk factors
- Controlling risk factors will help you manage the disease
- Risk factors that may be modified include smoking, elevated cholesterol levels, elevated blood glucose levels, lack of exercise, poor dietary habits, being overweight/obese and elevated blood pressure.
Medications that may be used to treat coronary artery disease include:
- Antiplatelet medications - These are medications that are used to prevent platelets in the blood from sticking together and causing clots. These drugs may include: aspirin, clopidogrel (Plavix), ticlopidine (Ticlid), and prasugrel.
- Antihyperlipidemic Medications - used to lower lipids (fats) in the blood, particularly low-density lipid (LDL) cholesterol. Statins are a group of antihyperlipidemic medications and include simvastatin (Zocor), atorvastatin (Lipitor), and pravastatin (Pravachol), among others. Bile acid sequestrants — colesevelam, cholestyramine and colestipol — and nicotinic acid (niacin) are two other types of medications that may be used to reduce cholesterol levels.
- Antihypertensives - These are medications used to lower blood pressure. There are several different groups of medications that act in different ways to lower blood pressure
With this procedure, a balloon is used to create a bigger opening in the vessel to increase blood flow. Although angioplasty is performed 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 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 performed in people who have angina (chest pain) and coronary artery disease (where plaque has built up in the arteries). 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 obstruction. Veins are usually taken from the leg, but arteries from the chest or arm may also be used to create a bypass graft.