Coronary Artery Disease affects the blood vessels (arteries) on the surface of the heart. These arteries bring blood (rich with oxygen and nutrients) to the heart muscle. Ageing and other complex factors cause these ordinarily soft and compliant blood vessels to harden. In addition, fat, cholesterol and minerals from the blood are deposited on the inner surface of the coronary arteries. When this material builds up, they form a plaque. A raised plaque may restrict the blood flow through the coronary artery. A raised plaque may also change the surface of the artery from smooth to rough, and these rough surfaces may stimulate the formation of a blood clot, which may slowly build up and narrow the artery even more. A blood clot can also build up quickly and abruptly close off the artery.
If you have an increased risk of Coronary Artery Disease (CAD) or certain symptoms of the disease, your doctor may recommend a Stress test, or exercise electrocardiogram (ECG). The Stress test measures changes in the electrical activity of your heart as you perform controlled exercice. This test can show if there has been damage to your heart. If the results of the Stress test indicate a need for further testing, your doctor may arrange for you to have a Coronary Angiogram. The coronary angiogram is the most useful test for diagnosing CAD because it allows the doctor to see exactly where the coronary arteries are narrowed or blocked.
Before the angiogram begins, you will received a local anesthetic or pain medicine. The doctor inserts an introducer sheath into an artery in your groin or through an incision in your arm. Then the doctor inserts a long tube called guiding catheter, into the artery and advances it into the blocked artery. By injecting a contrast dye that can be seen on an X-ray screen, the doctor can observe the arteries in your heart. You may be asked to take a deep breath and hold it while the doctor is taking the angiogram. Any narrowing or blockage that exists can then be identified. In some cases, the doctor performs a primary angioplasty, or balloon procedure, immediately following the angiogram in order to open the coronary artery for blood flow.
If a coronary artery suddenly closes, blood flow to a part of the heart may stop completely. In this case, some of the heart muscle may be permanently damaged. This is often accompanied by severe chest pain that won't go away. This is called myocardial infarction, or more commonly, a heart attack. The heart muscle can heal but muscle is replaced by scar tissue that doesn't contract. If the scar is small, recovery can be complete. If the scar is large it may permanently affect the pumping ability of the heart. It is therefore important that blood supply to the heart muscle should be restored before a heart attack can occur.
Your doctor will discuss the risks that specifically relate to your condition.