Coronary artery disease
The leading cause of heart attacks
Coronary artery disease (CAD) is a blockage of the arteries leading to the heart. While symptoms can take different forms, they all have the same cause: the heart muscle isn't getting enough blood and oxygen.
To work normally, the heart muscle (myocardium) needs a continuous supply of oxygen-rich blood. But as the coronary arteries get narrower, ischemia (inadequate blood supply) can develop. The most common cause of myocardial ischemia is coronary artery disease. Coronary artery disease causes heart attacks.
But the best approach to CAD is prevention, and many of the risk factors can be avoided or minimized with relatively simple lifestyle modifications.
Coronary artery disease can cause angina pectoris (chest pain), congestive heart failure, and sudden death. All of these effects of CAD have one thing in common: not enough oxygen is reaching the heart.
The risk of CAD increases with elevated levels of total cholesterol and low-density lipoprotein cholesterol (LDL, or "bad cholesterol") in the blood, but decreases when your levels of high-density lipoprotein (HDL, or "good cholesterol") increase. In other words, the higher your total and bad cholesterol levels are, the more likely you are to develop CAD.
Symptoms often don't appear until coronary artery disease reaches an advanced stage, but the numerous effective treatments for CAD range from lifestyle modifications to drugs to surgery.
How Common Is CAD?
In the United States, CAD is the leading cause of death in both genders, accounting for about one-third of deaths each year. The American Heart Association estimates that more than 12 million people have some form of CAD.
Goals of Treatment
The immediate goal in treating coronary artery disease is to halt or at least slow its progress. Your doctor may prescribe medications to help lower cholesterol levels if diet modifications and other lifestyle approaches fail. Drug therapy can also help control high blood pressure and diabetes, two other risk factors.
Lifestyle changes diet, exercise, and smoking cessation are critical. Cigarette smoking is the most important preventable risk factor in CAD.
Once you're diagnosed with CAD, your doctor will begin monitoring your overall health status, keeping a close watch on your blood pressure and your cholesterol and triglyceride levels. Your doctor can direct you to helpful resources for dietary counseling and smoking cessation if necessary.
The following treatments are general measures aimed at keeping CAD under control:
- Aerobic exercise: 30 to 45 minutes, four to five times a week at moderate intensity
- Weight loss, if needed, to reach and maintain normal body weight
- Low-fat, low-cholesterol, high-fiber diet
- Correction and control of abnormal blood-cholesterol levels
- Smoking cessation
- Maintenance of normal blood pressure and normal blood sugar levels
- Stress reduction
Blood-pressure-lowering agents that may include dieuretics, beta-blockers, calcium channel blockers, ACE inhibitors, vasodilators, and others
The two most commonly performed procedures to unblock the blood vessels leading to the heart are angioplasty and coronary bypass surgery, but a relatively new treatment called transmyocardial revascularization also shows promise for certain people. The location and severity of the disease in the coronary arteries determine which procedure is chosen.
- Coronary bypass surgery
- Transmyocardial revascularization
Healthcare Professionals Who May Be Involved in Treatment
The types of doctors who may be involved in treating and managing this condition include:
- Family physicians
- Critical care physicians
- Thoracic surgeons
- Cardiac surgeons
Activity & Diet Recommendations
Exercise is an important component of treating the underlying cause of CAD and is especially helpful in preventing development of heart disease. A program of aerobic exercise can improve circulation, reduce cholesterol, and control obesity and diabetes, among other factors contributing to coronary artery disease.
The connection between diet and heart disease is well established and many experts recommend a low-fat, high-fiber diet for patients with coronary artery disease. Here are some general guidelines for healthier eating:
- Avoid foods high in saturated fats, such as meats, eggs, cheeses, and other dairy products
- Eat plenty of whole grains, breads, and cereals instead of white and refined grains
- Eat lots of fresh fruits and vegetables with meals and as snacks
- Eat legumes such as beans, peas, and lentils in soups and salads
Monitoring the Condition
Keep a close watch on your cholesterol and triglyceride levels. Stick to your exercise and diet programs.
Possible complications of CAD include the following:
- Angina pectoris and unstable angina
- Heart attack
- Sudden cardiac death due to arrhythmias
- Congestive heart failure
Quality of Life
Depending on the severity and stage of coronary artery disease, available treatments range from lifestyle adjustments to major surgery. Which treatment is right for you depends on your individual situation. Making lifestyle changes, like improving your diet, quitting cigarettes, gradually increasing exercise, and reducing stress, can improve your overall quality of life and reduce your risk of the serious consequences of CAD, such as a heart attack.
Considerations for Women
Some studies suggest that estrogen replacement therapy after menopause in women with coronary artery disease may decrease your chances of experiencing angina. Talk to your doctor about whether this option is right for you.
Considerations for Older People
Older people are particularly at risk for coronary artery disease because the effects of risk factors such as high blood pressure build up over time. The coronary arteries nourishing the heart also become thicker and lose their elasticity with age. Stress associated with loneliness or depression can also put you at risk for any illness.
Considerations for Children and Adolescents
Coronary artery disease doesn't develop overnight. Fatty streaks and deposits can begin forming in children as young as three years old. Establishing healthy habits in childhood such as eating right and exercising can prevent serious health consequences in adulthood.
Last updated 23 May 2012
- Arteriosclerotic heart disease
- Coronary heart disease
- Coronary arteriosclerosis
- Ischemic heart disease
- Coronary artery insufficiency
Over time, fatty deposits (called atheromas or plaques) gradually build up in the large branches of the two main coronary arteries that supply the heart with blood. This gradual process is known as atherosclerosis. Plaque deposits bulge into the arteries and narrow them. As the deposits get bigger, pieces may rupture and enter the bloodstream, or small blood clots may form on their surfaces.
As the arteries narrow, blood flow to the heart decreases. Less blood equals less oxygen and decreased heart function.
The many risk factors for CAD include the following:
- High blood pressure
- Elevated LDL (low-density lipoprotein)
- Decreased HDL (high-density lipoprotein)
- Cigarette smoking
- Diabetes mellitus (uncontrolled)
- Sustained psychological stress
- Sedentary lifestyle
- Increasing age
- Male gender
- Family history of CAD and/or cholesterol disorder
- Elevated levels of fats (triglycerides)
Symptoms & Diagnosis
Some people with CAD have no tell-tale symptoms, but most people experience one or more of the following:
- Chest discomfort or pain (angina)
- Shortness of breath
- Irregular heart rhythm
- Foot swelling
- Quickened heart pace
Conditions That May Be Mistaken for Coronary Artery Disease
Several other conditions may simulate CAD since they also cause chest pain and shortness of breath:
- Gastrointestinal disorders such as peptic ulcer, indigestion, hiatal hernia, gallbladder disease, and spasms or inflammation of the esophagus
- Chronic shortness of breath (dyspnea)
- Blood clot in the lung, pneumonia, or pleurisy
- Inflammation of the membrane around the heart (pericarditis)
- Inflammation of or damage to the ribs
- Disease of the spinal nerve roots (radiculopathy)
- Inflammation of the gallbladder (cholecystitis)
- Psychological disorders due to panic or anxiety
- Cervical or thoracic spine disease
- Aortic aneurysm: injury of the tissue in the wall of aorta (the major artery carrying blood out of the heart)
How Is Coronary Artery Disease Diagnosed?
Checking your blood-cholesterol level should be part of your routine physical if you are over age 30. Men over 45 and women over 55 should have a cholesterol test annually. If your physician suspects that you have coronary artery disease, further testing is required to confirm the diagnosis:
- Your medical history and physical exam, including blood pressure
- Blood tests
- Electrocardiogram (EKG or ECG)
- Exercise testing
- Various methods of imaging
Laboratory blood tests for diabetes and for detecting levels of triglycerides, total cholesterol, LDL, and HDL are usually helpful to the diagnosis.
- Electrocardiogram (EKG)
- Exercise stress tests measure blood pressure, heartbeat, and breathing rate as well as an EKG, during exercise. This test can show if not enough blood (or oxygen) is reaching the heart during exercise.
Imaging allows your physician to locate the narrowed artery, which is helpful in determining which therapy is best for your condition.
- Coronary arteriography: A doctor guides a thin plastic tube through an artery in your arm or leg and into the coronary arteries, and then injects a liquid dye visible in x-rays through the catheter. High-speed X-ray movies show the liquid as it flows through the arteries. Doctors can identify blockages in the arteries by tracing the liquid's flow.
- Radionuclide scintigraphy: An imaging technique that involves the use of radioactive elements to demonstrate blood flow in the heart.
- Stress echocardiography: A diagnostic procedure that studies the structure and motion of the heart.
- Stress thalium: Imaging test to measure cardiac function and blood flow.
Self care & Prevention
Preventing Coronary Artery Disease
Preventive measures can substantially lower your risk for heart disease. The following lifestyle choices are particularly helpful in preventing the underlying coronary artery disease that can cause a heart attack:
- Stop smoking
- Lose weight
- Exercise regularly
- Reduce stress
- Eat a healthy, low-fat diet high in fiber and complex carbohydrates