Angina, also called angina
pectoris, is chest pain or discomfort that occurs when the muscle of the heart (see cardiac muscle) doesn't get
enough blood. It may feel like pressure or a squeezing pain in the chest.
The pain may also occur in the 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. CAD 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, which decreases the oxygen supply to the heart muscle.
The three types of angina are stable, unstable, and variant (Prinzmetal's).
It is very important to know the differences among the types.
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.
- 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 recognize the pattern and can predict when it will
- 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.
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 (CAD). Sometimes, other types
of heart disease or uncontrolled high
blood pressure can cause angina.
In CAD, 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
- By forming blood clots that partially or totally block the artery
|An artery with normal blood flow (figure A) and an
artery containing plaque buildup (figure B). Credit: National Institutes
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
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 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 or 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?
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 percent of cases of
angina. People with variant angina are often younger than those with other
forms of angina.
Signs and symptoms
Pain and discomfort are the main symptoms of angina. These symptoms
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
- 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
Symptoms vary based on the type of 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
The pain or discomfort:
- Often occurs at rest, while sleeping at night, or with little physical
- 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
The pain or discomfort:
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.
- Usually occurs at rest and during the night or early morning hours
- Tends to be severe
- Is relieved by angina medicine
To find out if you have angina, your doctor will:
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:
- 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
- Electrocardiogram (ECG or EKG). This test measures the rate and regularity of your heartbeat.
Some people with angina have a normal EKG.
- Stress test. Some heart
problems are easier to diagnose when your heart is working harder and
beating faster than when it's at rest. During stress testing, you exercise
(or are given medicine if you are unable to exercise) to make your heart
work harder and beat faster while heart tests are performed.
During exercise stress testing, your blood
pressure and EKG readings are monitored while you walk or run on
a treadmill or pedal a bicycle. Other heart tests, such as nuclear heart
scan or echocardiography (see below for more information on these tests),
also can be done at the same time. These would be ordered if your doctor
needs more information than the exercise stress test can provide about
how well your heart is working.
If you are unable to exercise, a medicine can be injected through an
intravenous line (IV) into your bloodstream to make your heart work
harder and beat faster, as if you are exercising on a treadmill or bicycle.
Nuclear heart scanning or echocardiography is then usually done.
During nuclear heart scanning, radioactive tracer is injected into your
bloodstream, and a special camera shows the flow of blood through your
heart and arteries. Echocardiography uses sound waves to show blood
flow through the chambers and valves of your heart and to show the strength
of your heart muscle.
Your doctor also may order two newer tests along with stress testing
if more information is needed about how well your heart works. These
new tests are magnetic
resonance imaging (MRI) and positron
emission tomography (PET) scanning of the heart. MRI shows detailed
images of the structures and beating of your heart, which may help your
doctor better assess if parts of your heart are weak or damaged. PET
scanning shows the level of chemical activity in different areas of
your heart. This can help your doctor determine if enough blood is flowing
to the areas of your heart. A PET scan can show decreased blood flow
caused by disease or damaged muscles that may not be detected by other
- 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 provides your doctor with moving pictures of the blood passing
through your heart's chambers and arteries and shows the level of blood
flood to the heart muscle. A small amount of a radioactive tracer is
injected into your bloodstream through a vein, usually in your arm.
A special camera is placed in front of your chest to show where the
tracer lights up in healthy heart muscle and where it doesn't light
up (in heart muscle that has been damaged or has a blocked artery).
There are different types of nuclear heart scans. Most scans have two
phases – taking pictures of the heart at rest and while it is
beating faster (called a stress test), although sometimes only a rest
scan is done. Many heart problems show up more clearly when your heart
is stressed than when it is at rest. By comparing the nuclear heart
scan of your heart at rest to your heart at "stress," your doctor can
determine if your heart is functioning normally or not.
- Echocardiogram. This
test uses sound waves to create a moving picture of your heart. Echocardiogram
provides information about the size and shape of your heart and how
well your heart chambers and valves are functioning. The test also can
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. There are several different types
of echocardiograms, including a stress echocardiogram. During this test,
an echocardiogram is done both before and after your heart is stressed
either by having you exercise or by injecting a medicine into your bloodstream
that makes your heart beat faster and work harder. A stress echocardiogram
is usually done to find out if you have decreased blood flow to your
heart (coronary artery disease).
- Cardiac catheterization.
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 catheterization. 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
Your doctor may also order blood tests,
- A fasting lipoprotein profile to check your cholesterol levels.
- Fasting glucose test to check your blood
- 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 hemoglobin in your blood. Hemoglobin is the part of red blood cells that carries
oxygen to all parts of your body.
Treatment for angina includes lifestyle changes, medicine, special procedures,
and cardiac rehabilitation. The main goals of treatment are to:
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.
- Reduce the frequency and severity of symptoms
- Prevent or lower the risk of heart attack and death
The first thing that you need to do is change your living habits to avoid
bringing on an episode of angina.
You can also make other lifestyle changes, for example:
- 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
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:
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
- Relieve an episode that is occurring by using the medicine when the
- 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
Other medicines can be used to treat angina:
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.
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
- Coronary artery
bypass grafting. 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.
Your doctor may prescribe cardiac
rehabilitation (rehab) for angina or after bypass surgery, angioplasty,
or a heart attack.
The cardiac rehab team may include:
Rehab has two parts:
- Your family doctor
- A heart specialist
- A surgeon
- Exercise specialists
- Physical therapists and occupational therapists
- Psychologists or other behavior therapists
- 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, counseling, 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
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
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:
After several episodes, you will learn to recognize 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:
- What causes the pain to occur
- What it feels like
- How long it usually lasts
- Whether it is relieved by 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.
- Occurring more often
- Lasting longer
- Being more severe
- Occurring without exertion
- Not going away with rest or medicine
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:
Long-acting nitrate preparations should be used regularly as prescribed
by your doctor.
- 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.
Men with impotence (erectile dysfunction) who take sildenafil (ViagraŽ)
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, 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 counseling 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
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:
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.
- 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
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.
Source: U.S. National
Heart, Lung and Blood Institute