Online Medicine Resource: ANGINA

What Is Angina?

Angina is chest pain or discomfort that occurs when your heart muscle does not get enough blood. Angina may feel like pressure or a squeezing pain in your chest. The pain may also occur in your shoulders, arms, neck, jaw, or back. It may also feel like indigestion.

Angina is a symptom of coronary artery disease (CAD), the most common type of heart disease. Coronary artery disease occurs when plaque builds up in the coronary arteries. This buildup of plaque is called atherosclerosis. As plaque builds up, the coronary arteries become narrow and stiff. Blood flow to the heart is reduced. This decreases the oxygen supply to the heart muscle.

Types of Angina

The three types of angina are stable, unstable, and variant (Prinzmetal's). It is very important to know the differences among the types.

Stable angina. Stable angina is the most common type. It occurs when the heart is working harder than usual.
- There is a regular pattern to stable angina. After several episodes, you learn to recognise the pattern and can predict when it will occur.
- The pain usually goes away in a few minutes after you rest or take your angina medicine.
- Stable angina is not a heart attack but makes it more likely that you will have a heart attack in the future.
Unstable angina. Unstable angina is a very dangerous condition that requires emergency treatment. It is a sign that a heart attack could occur soon. Unlike stable angina, it does not follow a pattern. It can occur without physical exertion and is not relieved by rest or medicine.
Variant angina. Variant angina is rare. It usually occurs at rest. The pain can be severe and usually occurs between midnight and early morning. It is relieved by medicine.

Not all chest pain or discomfort is angina. Chest pain or discomfort can be caused by a heart attack, lung problems (such as an infection or a blood clot), heartburn, or a panic attack. However, all chest pain should be checked by a doctor.

Other Names for Angina

Angina pectoris
Stable or common angina
Unstable angina
Variant angina
Prinzmetal's angina
Coronary artery spasms
Acute coronary syndrome

What Causes Angina?

Angina is caused by reduced blood flow to an area of the heart. This is most often due to coronary artery disease. Sometimes, other types of heart disease or uncontrolled high blood pressure can cause angina.

In coronary artery disease, the coronary arteries that carry oxygen-rich blood to the heart muscle are narrowed due to the buildup of fatty deposits called plaque. This is called atherosclerosis. Some plaque is hard and stable and leads to narrowed and hardened arteries. Other plaque is soft and is more likely to break open and cause blood clots. The buildup of plaque on the inner walls of the arteries can cause angina in two ways:

By narrowing the artery to the point where the flow of blood is greatly reduced
By forming blood clots that partially or totally block the artery

Stable Angina

Physical exertion is the most common cause of pain and discomfort from stable angina. Severely narrowed arteries may allow enough blood to reach the heart when the demand for oxygen is low (such as when you are sitting). But with exertion, like walking up a hill or climbing stairs, the heart works harder and needs more oxygen. Other causes include:

Emotional stress
Exposure to very hot or cold temperature
Heavy meals
Smoking

Unstable Angina

Unstable angina is caused by blood clots that partially or totally block an artery. If plaque in an artery ruptures or breaks open, blood clots may form. This creates a larger blockage. The clot may grow large enough to completely block the artery and cause a heart attack. Blood clots may form, partly dissolve, and later form again. Chest pain can occur each time a clot blocks an artery.

Variant Angina

Variant angina is caused by a spasm in a coronary artery. The spasm causes the walls of the artery to tighten. This narrows the artery, causing the blood flow to the heart to slow or stop. Variant angina may occur in people with and without CAD. Other causes of spasms in the arteries that supply the heart with blood are:

Exposure to cold
Emotional stress
Medications (vasoconstricting) that constrict or narrow blood vessels
Cigarette smoking
Cocaine use

Who Is At Risk for Angina?

More than 6 million people in the United States have angina.

People with coronary artery disease or who have had a heart attack are more likely to have angina.

Unstable angina occurs more often in older adults.

Variant angina is rare. It accounts for only about 2 out of 100 cases of angina. People with variant angina are often younger than those with other forms of angina.

What Are the Signs and Symptoms of Angina?

Pain and discomfort are the main symptoms of angina. These symptoms

Are often described as pressure, squeezing, burning, or tightness in the chest
Usually start in the chest behind the breastbone
May also occur in the arms, shoulders, neck, jaw, throat, or back
May feel like indigestion

Some people say that angina discomfort is hard to describe or that they can't tell exactly where the pain is coming from. Symptoms such as nausea, fatigue, shortness of breath, sweating, light-headedness, or weakness may also occur.

Symptoms vary based on the type of angina.

Stable Angina

The pain or discomfort:

Occurs when the heart must work harder, usually during physical exertion
Is expected, and episodes of pain tend to be alike
Usually lasts a short time (5 minutes or less)
Is relieved by rest or angina medicine
May feel like gas or indigestion
May feel like chest pain that spreads to the arms, back, or other areas

Unstable Angina

The pain or discomfort:

Often occurs at rest, while sleeping at night, or with little physical exertion
Is unexpected
Is more severe and lasts longer (as long as 30 minutes) than episodes of stable angina
Is usually not relieved with rest or angina medicine
May get continuously worse
May signal that a heart attack will happen soon

Variant Angina

The pain or discomfort:

Usually occurs at rest and during the night or early morning hours
Tends to be severe
Is relieved by angina medicine

Chest pain that lasts longer than a few minutes and is not relieved by rest or angina medicine may mean you are having—or are about to have—a heart attack. Call the emergency services right away.

How Is Angina Diagnosed?

To find out if you have angina, your doctor will:

Do a physical exam
Ask about your symptoms
Ask about your risk factors and your family history of coronary artery disease (CAD) or other heart disease

Sometimes, your doctor can diagnose angina by noting your symptoms and how they occur. Your doctor may order one or more tests to help make a diagnosis of angina. The tests your doctor may order include:

ECG (electrocardiogram). This test measures the rate and regularity of your heartbeat. Some people with angina have a normal ECG.
Exercise stress test. Some heart problems are easier to diagnose when the heart is working hard and beating fast. During stress testing, a patient exercises, or is given medicine, to make the heart work harder and beat fast while heart tests are performed. During exercise stress testing, blood pressure and ECG readings are monitored while the patient runs on a treadmill or pedals a bicycle.

Chest x ray. A chest x ray takes a picture of the organs and structures inside your chest. These include your heart, lungs, and blood vessels.
Nuclear heart scan. This test shows blood flow to the heart and any damage to the heart muscle. A radioactive dye (technetium or thallium) is injected into your bloodstream. A special camera can see the dye and find areas where blood flow is reduced. Nuclear heart scans are often taken while you are at rest and again after exercise. If you cannot exercise, a medicine is given to increase the workload of the heart. The before-and-after exercise scans are compared.
Echocardiogram. This test uses sound waves to create a picture of the heart. The picture is more detailed than an x-ray image. The test shows how well your heart chambers fill with blood and pump it to the rest of the body. An echocardiogram also can help identify areas of poor blood flow to the heart, areas of heart muscle that are not contracting normally, and previous injury to the heart muscle caused by poor blood flow. An echocardiogram can also be used with a stress test.
Cardiac catheterisation. A thin flexible tube (catheter) is passed through an artery in the groin (upper leg) or arm to reach the coronary arteries. Your doctor can determine pressure and blood flow in the heart's chambers, collect blood samples from the heart, and examine the arteries of the heart by x ray.
Coronary angiography. This test is done during cardiac catheterisation. A dye that can be seen by x ray is injected through the catheter into the coronary arteries. Your doctor can see the flow of blood through your heart and the location of blockages.

Your doctor may also order blood tests, such as:

A fasting lipoprotein profile to check your cholesterol levels.
Fasting glucose test to check your blood sugar level.
C-reactive protein (CRP) test. This blood test measures CRP, a protein in the blood that shows the presence of inflammation. Inflammation is the body's response to injury. High levels of CRP may be a risk factor for CAD.
A test to check for low haemoglobin in your blood. Haemoglobin is the part of red blood cells that carries oxygen to all parts of your body.

How Is Angina Treated?

Treatment for angina includes lifestyle changes, medicine, special procedures, and cardiac rehabilitation. The main goals of treatment are to:

Reduce the frequency and severity of symptoms
Prevent or lower the risk of heart attack and death

Lifestyle changes and medicine may be the only treatments needed if your symptoms are mild and are not getting worse. Unstable angina is an emergency condition that requires treatment in the hospital.

Lifestyle Changes

The first thing that you need to do is change your living habits to avoid bringing on an episode of angina.

Slow down or take rest breaks, if angina comes on with exertion.
Avoid large meals and rich foods that leave you feeling stuffed, if angina comes on after a heavy meal.
Try to avoid situations that make you upset or stressed, if angina comes on with stress. Learn techniques to handle stress that can't be avoided.

You can also make other lifestyle changes, for example:

Eat a healthy diet to prevent or reduce high blood pressure, high blood cholesterol, and obesity
Quit smoking, if you smoke
Be physically active, as directed by your doctor
Lose weight, if you are overweight or obese.
Follow your doctor's orders and take all medicines as directed, especially if you have diabetes

Medications

Nitrates are the most commonly used medicines to treat angina. Fast-acting preparations are taken when angina occurs or is expected to occur. Nitrates relax and widen blood vessels, allowing more blood to flow to the heart while reducing its workload.

You can use nitrates in different forms to:

Relieve an episode that is occurring by using the medicine when the pain begins
Prevent an episode from occurring by using the medicine just before pain or discomfort is expected to occur
Reduce the number of episodes that occur by using the medicine regularly on a long-term basis

Nitroglycerin is the most commonly used nitrate for angina. Nitroglycerin that dissolves under your tongue or between your cheeks and gum is used to relieve an angina episode. Nitroglycerin in the form of pills and skin patches is used to prevent attacks of angina. These forms of nitroglycerin act too slowly to relieve pain during an angina attack.

Other medicines can be used to treat angina:

Beta blockers slow the heart rate and lower blood pressure. They can delay or prevent the onset of angina.
Calcium channel blockers relax blood vessels so that more blood flows to the heart, reducing pain from angina. Calcium channel blockers also lower blood pressure.
ACE (angiotensin-converting enzyme) inhibitors lower blood pressure and reduce the strain on the heart. They also reduce the risk of a future heart attack and heart failure.

People who have angina may also use:

Medicines to lower cholesterol levels.
Medicines to lower high blood pressure.
Oral antiplatelet medicines (such as aspirin and clopidigrel), taken daily, to stop platelets from clumping together to form blood clots. Platelets are small blood cells that circulate through your blood vessels and help stop bleeding by sticking together to seal small cuts or breaks in tiny blood vessels. Antiplatelet medicines may not be appropriate for some people because they increase the risk of bleeding. Discuss the benefits and risks with your doctor before starting therapy with aspirin or the other antiplatelet medicines.

Glycoprotein IIb-IIIa inhibitors are potent antiplatelet medicines that prevent clots from forming in your arteries. They are given intravenously in hospitals for the treatment of angina or during and after angioplasty.
Anticoagulants to prevent clots from forming in your arteries and blocking blood flow.

Special Procedures

When medicines and other treatments do not control angina, special (invasive) procedures may be needed. Two commonly used procedures are:

Angioplasty. This procedure opens blocked or narrowed coronary arteries. It can improve blood flow to your heart, relieve chest pain, and possibly prevent a heart attack. Sometimes a stent is placed in the artery to keep it propped open after the procedure.
Coronary artery bypass surgery. This procedure uses arteries or veins from other areas in your body to bypass your blocked coronary arteries. Bypass surgery improves blood flow to your heart, relieves chest pain, and can prevent a heart attack.

Cardiac Rehabilitation

Your doctor may prescribe cardiac rehabilitation (rehab) for angina or after bypass surgery, angioplasty, or a heart attack.

The cardiac rehab team may include:

Doctors
- Your family doctor
- A heart specialist
- A surgeon
Nurses
Exercise specialists
Physical therapists and occupational therapists
Dietitians
Psychologists or other behaviour therapists

Rehab has two parts:

Exercise training. This helps you learn how to exercise safely, strengthen your muscles, and improve your stamina. Your exercise plan will be based on your individual ability, needs, and interests.
Education, counselling, and training. This helps you understand your heart condition and find ways to reduce your risk of future heart problems. The cardiac rehab team will help you learn how to cope with the stress of adjusting to a new lifestyle and to deal with your fears about the future.

How Can Angina Be Prevented?

You can prevent or lower your risk for heart disease and angina by making lifestyle changes and getting treatment for related conditions.

Make Lifestyle Changes

You can prevent or lower your risk for angina and heart disease by making healthy lifestyle choices:

Eat a healthy diet to prevent or reduce high blood pressure, high blood cholesterol, and obesity.
Quit smoking, if you smoke
Be physically active, as directed by your doctor
Lose weight, if you are overweight or obese

Treat Related Conditions

In addition to making lifestyle changes, you can help prevent angina and heart disease by treating related conditions, such as:

High blood cholesterol. If you have high cholesterol, follow your doctor's advice about lowering it. Take medications to lower your cholesterol as directed.
High blood pressure. If you have high blood pressure, follow your doctor's advice about keeping your blood pressure under control. Take blood pressure medications as directed.
Diabetes (high blood sugar). If you have diabetes, follow your doctor's advice about keeping your blood sugar levels under control. Take medicines as directed.
Overweight or obesity. If you are overweight or obese, talk to your doctor about how to lose weight safely.

Living With Angina

Angina is not a heart attack, but it does mean that you are at greater risk of having a heart attack than someone who does not have angina. The risk is even higher if you have unstable angina. For these reasons, it is important that you know:

The usual pattern of your angina, if you have it on a regular basis
About your medicine
How to control your angina
The limits of your physical activity
How and when to seek medical attention

Know the Pattern of Your Angina

Stable angina usually occurs in a pattern. You should know:

What causes the pain to occur
What it feels like
How long it usually lasts
Whether it is relieved by rest or medicine

After several episodes, you will learn to recognise when you are having angina. It is important for you to notice if the pattern starts to change. Changes in the pattern to look for may include:

Occurring more often
Lasting longer
Being more severe
Occurring without exertion
Not going away with rest or medicine

These changes in the pattern may be a sign that your symptoms are getting worse or becoming unstable. You should seek medical attention. Unstable angina suggests that you are at high risk for a heart attack very soon.

Know Your Medicines

You should know what medicines you are taking, the purpose of each, how and when to take them, and possible side effects. It is very important that you know exactly when and how to take fast-acting nitroglycerin or other nitrates to relieve chest pain. They should be taken:

Immediately when pain begins or before stressful activity
Three times spaced 5 minutes apart if pain does not go away

Always sit down before taking nitroglycerin.

Long-acting nitrate preparations should be used regularly as prescribed by your doctor.

Men with impotence (erectile dysfunction) who take sildenafil (Viagra®) should talk with their doctor. Taking sildenafil and nitroglycerin or other nitrates within 24 hours of each other can cause serious problems.

Ask your doctor about your other medicines. Also, see the Treatment section to read descriptions of the medicines that you are taking.

Know How To Control Your Angina

After several episodes, you will know the level of activity, stress, and other things that can bring on your angina. By knowing this, you can take steps to prevent or lessen the severity of episodes.

Physical exertion. Know what level of activity brings on your angina and try to stop and rest before chest pain starts. For example, if walking up a flight of stairs leads to chest pain, then stop halfway and rest before continuing. When chest pain occurs during exertion, stop and rest or take your angina medicine. The pain should go away in a few minutes. If the pain does not go away or lasts longer than usual, call 9–1–1 and get emergency care.
Emotional stress. Anger, arguing, and worrying are examples of emotional stress that can bring on an angina episode. Try to avoid or limit exposure to situations that cause these emotions. Exercise and relaxation can help relieve stress. Alcohol and drug use play a part in causing stress and do not relieve it. If stress is a problem for you, talk with your doctor about getting counselling to help you deal with stress.
Eating large meals. If this leads to chest pain, eat smaller meals. Also, avoid eating rich foods.

Know the Limits of Your Physical Activity

Most people with stable angina can continue their normal activities. This includes work, hobbies, and sexual relations. However, if you engage in very strenuous activity or have a stressful job, you may need to discuss this with your doctor.

Know How and When To Seek Medical Attention

If you have angina, you are at high risk of having a heart attack. Therefore, it is very important that you and your family know how and when to seek medical attention. Talk to your doctor about making an emergency action plan. The plan should include:

The signs and symptoms of a heart attack
Instructions for the prompt use of aspirin and nitroglycerin
How to access emergency medical services in your community
The location of the nearest hospital that offers 24-hour emergency heart care

Be sure to discuss your emergency plan with your family members. Take action quickly if your chest pain becomes severe, lasts longer, or is not relieved by rest or medicine.

Sometimes, it may be difficult to tell the difference between unstable angina and a heart attack. Most heart attack victims wait 2 hours or more after their symptoms begin before they seek medical help. This delay can result in death or lasting heart damage.

Key Points

Angina is chest pain or discomfort that occurs when your heart muscle does not get enough blood. Angina may feel like pressure or a squeezing pain in your chest. The pain may also occur in your shoulders, arms, neck, jaw, or back.
Most people with angina have coronary artery disease, with narrowed arteries due to atherosclerosis. When arteries are narrowed, blood flow to the heart is reduced.
More than 6 million people in the United States have angina.
The most common types of angina are stable angina and unstable angina. A less common type of angina is called variant angina.
Stable angina is chest pain or discomfort that occurs when the heart is working harder than usual. Pain from stable angina goes away when you rest or take your angina medicine. Angina medicine, such as nitroglycerin, helps widen and relax the arteries so that more blood can flow to the heart.
Unstable angina is a very dangerous condition that requires emergency treatment. Unstable angina is a sign that a heart attack could occur soon. Unstable angina can occur without physical exertion. It is not relieved by rest or medicine.
Variant angina is caused by a spasm in a coronary artery. The spasm causes the walls of the artery to tighten. This narrowing of the artery slows or stops blood flow to the heart.
Doctors diagnose angina based on your health history, your family's health history, a physical exam, and the results of various tests.
Angina is usually treated with medicines such as nitrates (nitroglycerin). People with angina may need to take other medicines to lower their blood pressure or cholesterol. They also may take medicine to prevent blood clots.
To prevent and treat angina, it is important to make changes to improve your health. Get regular physical activity, maintain a healthy weight, don't smoke, and eat a healthy diet that is low in saturated fat and cholesterol. A cardiac rehab programme can be helpful for many people with angina.
When medicines and lifestyle changes do not control angina, special procedures may be needed. Angioplasty and coronary artery bypass surgery are two common procedures used to treat angina.
If you have angina, it is important to know the pattern of your angina, about your medicine, how to control your angina, and the limits on your physical activity. You should know how and when to seek medical help