What is angina pectoris?
Angina, or angina pectoris, is a recurring discomfort. It's usually located near the center of the chest. The pain or discomfort occurs when the blood supply to part of the heart muscle doesn't meet the heart's needs. As a result, the heart doesn't get enough oxygen and nutrients. The discomfort occurs most often during exercise or emotional stress. That's when the heart rate and blood pressure increase, and the heart muscle needs more oxygen. Anginal pain or discomfort is usually brief, lasting just a few minutes. People describe it as a heaviness, tightness, oppressive pain, burning, pressure or squeezing. Usually it's located behind the breastbone. Sometimes it spreads to the arms, neck or jaws. It may also cause numbness in the shoulders, arms or wrists.
What is the relationship between angina and a heart attack?
Angina is different from a heart attack. Both relate to the blood flow through the coronary arteries (which bring blood to the heart muscle), but there is a key difference. With angina, the blood flow is reduced, especially when the heart must do more work. This imbalance between oxygen supply and demand is temporary leading to discomfort in the chest.
With a heart attack, the blood flow to part of the heart muscle is suddenly cut off when a coronary artery is blocked. The chest pain that results is usually more severe and lasts longer. As a general rule, attacks of angina don't permanently damage the heart muscle; a heart attack does. Many people who have angina have never had a heart attack, although angina can develop after one.
What causes Angina?
Angina and heart attack have the same root cause: atherosclerosis. This is the narrowing of the coronary arteries caused by deposits of fatty substances such as cholesterol. It usually starts early in life. Everyone has it to some degree by middle age.
How is angina diagnosed?
Usually your doctor can accurately diagnose angina from your description of symptoms. If you're suffering from it, it's possible for your physical examination and resting electrocardiogram to be entirely normal. That's why your doctor may recommend an exercise test to increase your heart's demand for blood and oxygen. An electrocardiogram recorded during an exercise test can show if your heart isn't getting enough oxygen. Sometimes it's hard to diagnose angina even after a medical history, a physical examination and an exercise test. If that's the case, your doctor may order a thallium stress test. This is a special exercise test in which a radioisotope (thallium) is injected into a vein during exercise. It uses radioactivity detectors and computers to measure the blood flow to the heart muscle during exercise.
Your doctor may decide that a coronary arteriogram is necessary. This is an x-ray movie of your coronary arteries. It shows blood flow patterns as a radiopaque substance (a liquid that blocks x-rays) is injected into your arteries. If you have angina, an arteriogram will show if your coronary arteries are blocked or constricted, where the blockage is and how severe it is.
How is angina treated?
Nitroglycerin usually works well to relieve chest discomfort from angina. It can be used to prevent discomfort, too. It's usually taken in tiny tablets, which are put under the tongue to dissolve. It may also be prescribed as an oral spray. Nitroglycerin tablets are inexpensive and act quickly. Keep a fresh, sealed supply of them on hand at all times. As a general rule, avoid moving your tablets from their original, dark glass bottle, because they're sensitive to heat, light and air. And always use the medicine as directed by your doctor. Be sure to carry your nitroglycerin with you at all times. Take a tablet just before starting an activity you know is likely to cause anginal discomfort. Also, take a tablet if your discomfort doesn’t begin to go away within a minute or two after you've stopped the activity, or if discomfort occurs when you aren't active. Tell your doctor what usually causes your angina so he or she can advise you about preventing attacks.
It may take several tablets a day to control your symptoms, Nitroglycerin is safe and not habit forming, so don't be afraid to take it. Ask your doctor what to do if nitroglycerin doesn't completely relieve your angina or if the pain starts to come more often or gets worse. Some people who take nitroglycerin get a short headache or a feeling of fullness in the head. Often these symptoms disappear after they've taken nitroglycerin several times.
If you have this problem and it doesn't get better, your doctor may want to reduce the dosage in each tablet. Long acting forms of nitroglycerine are also available. The come in the form of long acting tablets, patches, and nitroglycerin paste.
How can coronary blood flow be improved?
If medication doesn't control your angina, your doctor may suggest percutaneous transluminal coronary angioplasty (PTCA) or one of its variations. This procedure can increase blood flow in a narrowed blood vessel.
In this treatment the doctor inserts a balloon-tipped catheter into an artery. When the tip is guided to where the blood vessel is narrowed, the balloon is inflated, compressing the plaque. Then the balloon is deflated and the catheter withdrawn. Variations include the use of devices to remove plaque (grinding or shaving devices) and the use of stents (metallic sleeves which help open the artery).
What is the role of heart surgery?
If you keep having frequent or disabling angina despite using medications, or if your coronary arteries are badly blocked, you may need surgery. Your doctor may advise coronary artery bypass surgery on one or more of your arteries. In this operation, a vein taken from the leg or an artery taken from the chest wall is grafted onto the blocked artery, bypassing the blocked area. If more than one artery is blocked, each one may receive a bypass.