Like any muscle, the heart needs a constant source of oxygen and nutrients that are taken to it by the blood in the coronary arteries. When the coronary arteries become narrowed or clogged and cannot supply enough blood to the heart, the result is CHD. If not enough oxygen-carrying blood gets to the heart, the heart may react with suffering called angina. The pain is usually felt in the chest or sometimes in the left arm and shoulder. (However, the same insufficient blood supply may cause no indicators, a circumstance known as silent angina.)

When the blood supply is cut off completely, the end result is a heart attack. The portion of the heart that does not acquire oxygen starts to die, and many of the heart muscle may be completely impaired.

So what leads to CHD? CHD is caused by a thickening of the inside walls of the coronary arteries. This thickening, known as atherosclerosis, narrows the space through which blood can move, reducing and oftentimes entirely cutting off the source of oxygen and nutrients to the heart.

Atherosclerosis generally occurs when a person has high quantities of cholesterol, a fat-like substance, in the blood. Cholesterol and fat, going in the blood, build up on the walls of the arteries. The build-up narrows the arteries and can easily impede or block the flow of blood. When the amount of cholesterol in the blood is high, there is a bigger prospect that it will be deposited onto the artery walls. This progression begins in most people during childhood and the teenage years, and worsens as they get older.

In addition to high blood cholesterol, high blood pressure and smoking likewise add to CHD. On the average, each of these doubles your probability of getting heart disease. Because of this, a person who has all three risk factors is eight times more likely to acquire heart disease than someone who has none. Obesity and physical lack of exercise are other aspects that can contribute to CHD. Being obese increases the likelihood of developing high blood cholesterol and high blood pressure, and a sedentary lifestyle increases the dangers of heart attack. Regular exercising, good food regimen, and smoking cessation are critical to curbing the risk variables for CHD.

Among its symptoms are chest pain (angina) or shortness of breath, which may be the first evidence of CHD. A person may experience heaviness, tightness, agony, burning, pressure, or squeezing, usually behind the breastbone but often also in the arms, neck, or jaws. These signs usually bring the patient to a doctor for the first time. Nevertheless, some people suffer heart attacks without ever getting any of these symptoms.

It is important to learn that there is a huge range of seriousness for CHD. Some people have no symptoms at all, some have moderate irregular chest pain, and some have more pronounced and regular ache. Still others have CHD that is serious enough to make regular daily actions difficult.

Because CHD may differ so significantly from one person to another, the way a doctor diagnoses and treats CHD will also change a lot. The following explanations are standard guidelines to some exams and treatments that may or may not be employed, depending on the unique situation.

There is no one simple test--some or all of the following types of treatments may be needed. These diagnostic procedures are employed to determine CHD, to ascertain its particular degree and severity, and to rule out other likely reasons of the symptoms.

After taking a careful medical history and doing a physical examination, the doctor may employ some tests to observe how advanced the CHD is. The only certain means to detect and assess the level of CHD is coronary angiography (see below); other tests can indicate a problem but do not show exactly where it is.

An examination for CHD may include the following tests:

An electrocardiogram (ECG or EKG) is a graphic record of the electrical activity of the heart as it contracts and rests. Unusual heartbeats and some areas of injury, insufficient blood flow, and heart enlargement can be found on the records.

A stress test (also called a treadmill test or exercise ECG) is employed to document the heartbeat during exercise. This is accomplished since several heart problems only pop up when the heart is working hard. In the test, an ECG is done before, during, and after exercising on a treadmill; breathing rate and blood pressure may be measured as well. Exercise tests are useful but are not completely reliable; false positives (showing a problem where none exists) and false negatives (showing no problem when something is wrong) are fairly common.

Nuclear scanning is sometimes used to show damaged areas of the heart and reveal problems with the heart's pumping action. A tiny amount of radioactive material is injected into a vein, usually in the arm. A scanning camera tracks the nuclear material that is taken up by heart muscle (healthy areas) or not taken up (damaged areas).

Coronary angiography (or arteriography) is a test used to investigate the coronary arteries. A fine tube (catheter) is put into an artery of an arm or leg and passed through the tube into the arteries of the heart. The heart and blood vessels are then filmed while the heart pumps. The picture that is seen, called an angiogram or arteriogram, will show problems such as a blockage caused by atherosclerosis.

CHD is treated in a number of ways, depending on the severity of the disease. For many people, CHD is managed with lifestyle changes and medications. Others with severe CHD may need surgery. In any case, once CHD develops, it involves lifelong management.