Your doctor has diagnosed the pain or discomfort in your chest as angina. Angina pectoris, or angina, is a recurring discomfort. It usually lasts no more than a few minutes. It’s often in the center of the chest, behind the breastbone. People describe it as heaviness, tightness, pain, fullness, uncomfortable pressure or squeezing. Sometimes, the pain or discomfort spreads to one or both arms, or the back, neck, jaw, or stomach. It may also cause numbness in the shoulders, arms or wrists.
Angina occurs when your heart muscle doesn’t get the blood supply (and oxygen) it needs. That’s why you feel angina most often during physical activities or emotional stress. These are times when your heart rate and blood pressure increase and your heart muscles need more oxygen.
Angina and heart attack
Both angina and heart attack involve inadequate blood flow to the heart muscle, but there’s a key difference. In angina, the blood flow is reduced, especially when the heart must do more work. This temporarily reduced blood flow leads to chest discomfort.
In a heart attack, blood flow to part of the heart muscle is suddenly cut off when a coronary artery is blocked. The coronary arteries supply the heart muscle with blood. This resulting chest pain is usually more severe and lasts longer.
Angina attacks don’t permanently damage the heart muscle. However, the underlying problems that cause angina can lead to a heart attack, which does cause permanent damage. Other people only develop angina after a heart attack.
Your body has a way to increase the blood flow to the heart muscle when a coronary artery is partly blocked. Other nearby arteries may expand and tiny branches may open up to carry more blood to the affected area. This is called collateral circulation. If the collateral circulation becomes well developed, angina symptoms may decrease or even go away. This extra blood flow to the heart muscle can help prevent a heart attack. If a heart attack does occur, the permanent heart damage may be less severe.
Angina and heart attack have the same root cause atherosclerosis (see diagram). This is the buildup of deposits of fatty substances such as cholesterol, in the coronary arteries. Atherosclerosis usually starts early in life. Everyone has it to some degree by middle age.
Stable vs. unstable angina
Stable angina usually occurs following a certain amount of exertion, or a particular level of emotion. On the other hand, unstable angina often comes on suddenly out of the blue. The basic symptoms are the same as stable angina, but unstable angina may occur with little if any exertion, happens more often, and is far more severe, so the uncomfortable sensations of pressures and squeezing are painful.
Stable angina is often a manage-and-monitor situation. The unstable version, however, is a medical emergency that almost invariably involves a trip to the hospital and a battery of tests. Indeed, unstable angina is sometimes referred to as preinfarction angina to drive home the point that the risk of heart attack is high.
Diagnosis
Usually, your doctor can diagnose angina from your description of symptoms. Almost every angina patient, though, will get an electrocardiogram (ECG), which senses the electrical activity of the heart. An ECG can detect myocardial ischemia even when it isn’t producing angina. It can also help a doctor discover an irregular heartbeat that might be caused by ischemia or a myocardium (the heart muscles) thickened by chronic overwork.
Your resting ECG, though, can be entirely normal. That’s why your doctor may recommend an exercise test to increase your heart’s demand for blood and oxygen. An ECG recorded during an exercise test (called a stress test) can show if your heart isn’t getting enough oxygen.
Some patients go on to have echocardiograms, which use ultrasound waves to produce images of the heart. Others may get tests designed to show whether a coronary artery is blocked. High-speed CT scanners are increasingly used for this purpose, but the coronary angiogram, which involves injecting a dye into the arteries with a catheter so they show up better on an x-ray, remains the definitive exam for coronary artery blockage.
Experts have come up with “if this, then that” pathways for angina diagnosis. It’s beyond the scope of this article to delineate the many possibilities of those flowcharts: There are just too many contingencies. Suffice it to say that if the angina is unstable, many more tests will be ordered, and that the overriding purpose of the tests is to find out if a heart attack has started or is about to start. In either case, immediate treatment is started.
Treatment
Mild to moderate stable angina will almost always be treated with medications. Nitroglycerin is the iconic drug, and it remains the mainstay for quick relief from an angina episode, although there are also long-acting nitrate drugs that can be taken on a regular preventive basis.
Nitroglycerin is a potent vasodilator: It widens and relaxes arteries and veins, although its main effect seems to be on the veins. Wider veins decrease blood return to the heart, lessening its workload. Most often taken as a pill that dissolves on the tongue, nitroglycerin starts working in just a few minutes.
People with stable angina are also usually prescribed a beta blocker. By interfering with the action of epinephrine and norepinephrine, beta blockers slow down the heart so its need for blood is a little less urgent. If beta blockers are ineffective or the side effects are intolerable, calcium channel blockers are an alternative. They dilate the coronary arteries and also reduce the heart’s energy demands. Angiotensin-converting enzyme (ACE) inhibitors and angiotensin-receptor blockers (ARBs) also make demand-side adjustments, lowering blood pressure and relaxing arteries throughout the body.
Antiplatelet therapy is another prong in the angina treatment strategy. Platelets are cell-like particles in the blood that help it clot. Antiplatelet therapy makes platelets less “sticky,” reducing the risk that the clots that cause heart attacks (and strokes) will form. Tried-and-tested aspirin is the antiplatelet workhorse, but clopidogrel (Plavix) has come on strong as an alternative, especially for people who don’t respond to aspirin. An increasing number of angina patients are prescribed both drugs.
Angioplasty and coronary bypass are the two main “revascularization” procedures. Angioplasty, which involves using a catheter to open up the artery and then inserting a stent to keep it open, is less invasive than coronary bypass and is usually seen as the first choice if the atherosclerosis isn’t too severe. Coronary bypass, which uses arteries from other parts of the body to reroute coronary circulation, is a major operation and, as a rule, reserved for treatment of more complicated or widespread atherosclerosis.
What you can do
You can change your way of life to reduce the chance of angina attacks. The suggestions that follow can help you live more comfortably with angina.
• Control your physical activity. Moderate physical activity helps control weight and stress, and may be good for you. Still, take it easy at first. Ask your doctor about the best types and amounts of physical activity for you.
• Avoid emotional upsets. Any kind of emotional upset, including outbursts of temper, can trigger angina. Learning to control your emotions will help you control your angina.
• Adopt good eating habits. Like exercise, digestion causes your heart to work harder. Try to avoid large meals and rich foods that make you feel stuffed. Relax for a while after eating.
• Check with your doctor about alcohol. If you drink alcohol, do so in moderation. This means an average of one to two drinks per day for men and one drink for women. Drinking a moderate amount of alcohol helps some people relax and may be good for you, but drinking too much alcohol may be dangerous because it affects the heart.
• Don’t smoke cigarettes and avoid others’ smoke. Cigarette smoking is bad for everyone. If you have angina or any form of heart disease, it’s critical to stop smoking. Smoking increases the strain on your heart by causing blood vessels to constrict. It also causes your heart to beat faster, reduces oxygen in your blood, and makes it easier for blood to form clots. These effects often make angina worse.
• Control high blood pressure. High blood pressure increases the risk of developing heart disease, heart failure, and other circulatory disorders. It also increases the heart’s work and can make angina worse. Controlling blood pressure is essential, so follow your doctor’s advice about treatment.
The bottom line is: If you have angina, see your doctor. It can be life-saving!