Dr. MJ Bazos MD,
What Is Angina?
Angina pectoris ("angina") is a
recurring pain or discomfort in the chest that happens when some part of the
heart does not receive enough blood. It is a common symptom of coronary heart
disease (CHD), which occurs when vessels that carry blood to the heart become
narrowed and blocked due to atherosclerosis
Angina feels like a pressing or
squeezing pain, usually in the chest under the breast bone, but sometimes in the
shoulders, arms, neck, jaws, or back. Angina is usually precipitated by
exertion. It is usually relieved within a few minutes by resting or by taking
prescribed angina medicine.
Brings on Angina?
Episodes of angina
occur when the heart's need for oxygen increases beyond the oxygen available
from the blood nourishing the heart. Physical exertion is the most common
trigger for angina. Other triggers can be emotional stress, extreme cold or
heat, heavy meals, alcohol, and cigarette smoking.
Does Angina Mean a Heart Attack Is
About to Happen?
An episode of angina
is not a heart attack. Angina pain means that some of the heart muscle in not
getting enough blood temporarily—for example, during exercise, when the
heart has to work harder. The pain does NOT mean that the heart muscle is
suffering irreversible, permanent damage. Episodes of angina seldom cause
permanent damage to heart muscle.
contrast, a heart attack occurs when the blood flow to a part of the heart is
suddenly and permanently cut off. This causes permanent damage to the heart
muscle. Typically, the chest pain is more severe, lasts longer, and does not go
away with rest or with medicine that was previously effective. It may be
accompanied by indigestion, nausea, weakness, and sweating. However, the
symptoms of a heart attack are varied and may be considerably milder.
When someone has a repeating but
stable pattern of angina, an episode of angina does not mean that a heart attack
is about to happen. Angina means that there is underlying coronary heart
disease. Patients with angina are at an increased risk of heart attack compared
with those who have no symptoms of cardiovascular disease, but the episode of
angina is not a signal that a heart attack is about to happen. In contrast, when
the pattern of angina changes—if episodes become more frequent, last
longer, or occur without exercise—the risk of heart attack in subsequent
days or weeks is much higher.
who has angina should learn the pattern of his or her angina—what cause an
angina attack, what it feels like, how long episodes usually last, and whether
medication relieves the attack. If the pattern changes sharply or if the
symptoms are those of a heart attack, one should get medical help immediately,
perhaps best done by seeking an evaluation at a nearby hospital emergency room.
Is All Chest Pain "Angina?"
No, not at all. Not all chest pain is
from the heart, and not all pain from the heart is angina. For example, if the
pain lasts for less that 30 seconds or if it goes away during a deep breath,
after drinking a glass of water, or by changing position, it almost certainly is
NOT angina and should not cause concern. But prolonged pain, unrelieved by rest
and accompanied by other symptoms may signal a heart attack.
How Is Angina Diagnosed?
Usually the doctor can diagnose angina
by noting the symptoms and how they arise. However one or more diagnostic tests
may be needed to exclude angina or to establish the severity of the underlying
coronary disease. These include the electrocardiogram (ECG) at rest, the stress
test, and x- rays of the coronary arteries (coronary "arteriogram" or
The ECG records
electrical impulses of the heart. These may indicate that the heart muscle is
not getting as much oxygen as it needs ("ischemia"); they may also indicate
abnormalities in heart rhythm or some of the other possible abnormal features of
the heart. To record the ECG, a technician positions a number of small contacts
on the patient's arms, legs, and across the chest to connect them to an ECG
For many patients with
angina, the ECG at rest is normal. This is not surprising because the symptoms
of angina occur during stress. Therefore, the functioning of the heart may be
tested under stress, typically exercise. In the simplest stress test, the ECG is
taken before, during, and after exercise to look for stress related
abnormalities. Blood pressure is also measured during the stress test and
symptoms are noted.
A more complex
stress test involves picturing the blood flow pattern in the heart muscle during
peak exercise and after rest. A tiny amount of a radioisotope, usually thallium,
is injected into a vein at peak exercise and is taken up by normal heart muscle.
A radioactivity detector and computer record the pattern of radioactivity
distribution to various parts of the heart muscle. Regional differences in
radioisotope concentration and in the rates at which the radioisotopes disappear
are measures of unequal blood flow due to coronary artery narrowing, or due to
failure of uptake in scarred heart muscle.
The most accurate way to assess the
presence and severity of coronary disease is a coronary angiogram, an x-ray of
the coronary artery. A long thin flexible tube (a "catheter") is threaded into
an artery in the groin or forearm and advanced through the arterial system into
one of the two major coronary arteries. A fluid that blocks x-rays (a "contrast
medium" or "dye") is injected. X-rays of its distribution show the coronary
arteries and their narrowing.
is angina treated?
coronary artery disease that causes angina should be attacked by controlling
existing "risk factors." These include high blood pressure, cigarette smoking,
high blood cholesterol levels, and excess weight. If the doctor has prescribed a
drug to lower blood pressure, it should be taken as directed. Advice is
available on how to eat to control weight, blood cholesterol levels, and blood
pressure. A physician can also help patients to stop smoking. Taking these steps
reduces the likelihood that coronary artery disease will lead to a heart attack.
Most people with angina learn to
adjust their lives to minimize episodes of angina, by taking sensible
precautions and using medications if necessary.
Usually the first line of defense involves
changing one's living habits to avoid bringing on attacks of angina. Controlling
physical activity, adopting good eating habits, moderating alcohol consumption,
and not smoking are some of the precautions that can help patients live more
comfortably and with less angina. For example, if angina comes on with strenuous
exercise, exercise a little less strenuously, but do exercise. If angina occurs
after heavy meals, avoid large meals and rich foods that leave one feeling
stuffed. Controlling weight, reducing the amount of fat in the diet, and
avoiding emotional upsets may also help.
Angina is often controlled by drugs.
The most commonly prescribed drug for angina is nitroglycerin, which relieves
pain by widening blood vessels. This allows more blood to flow to the heart
muscle and also decreases the work load of the heart. Nitroglycerin is taken
when discomfort occurs or is expected. Doctors frequently prescribe other drugs,
to be taken regularly, that reduce the heart's workload. Beta blockers slow the
heart rate and lessen the force of the heart muscle contraction. Calcium channel
blockers are also effective in reducing the frequency and severity of angina
What if Medication Fails
to Control Angina?
recommend surgery or angioplasty if drugs fail to ease angina or if the risk of
heart attack is high. Coronary artery bypass surgery is an operation in which a
blood vessel is grafted onto the blocked artery to bypass the blocked or
diseased section so that blood can get to the heart muscle. An artery from
inside the chest (an "internal mammary" graft) or long vein from the leg (a
"saphenous vein" graft) may be used.
Balloon angioplasty involves inserting
a catheter with a tiny balloon at the end into a forearm or groin artery. The
balloon is inflated briefly to open the vessel in places where the artery is
narrowed. Other catheter techniques are also being developed for opening
narrowed coronary arteries, including laser and mechanical devices applied by
means of catheters.
Can a Person
With Angina Exercise?
Yes. It is
important to work with the doctor to develop an exercise plan. Exercise may
increase the level of pain-free activity, relieve stress, improve the heart's
blood supply, and help control weight. A person with angina should start an
exercise program only with the doctor's advice. Many doctors tell angina
patients to gradually build up their fitness level—for example, start with
a 5-minute walk and increase over weeks or months to 30 minutes or 1 hour. The
idea is to gradually increase stamina by working at a steady pace, but avoiding
sudden bursts of effort.
the difference between "stable" and "unstable" angina?
It is important to distinguish between
the typical stable pattern of angina and "unstable" angina.
Angina pectoris often recurs in a
regular or characteristic pattern. Commonly a person recognizes that he or she
is having angina only after several episodes have occurred, and a pattern has
evolved. The level of activity or stress that provokes the angina is somewhat
predictable, and the pattern changes only slowly. This is "stable" angina, the
most common variety.
appearing gradually, angina may first appear as a very severe episode or as
frequently recurring bouts of angina. Or, an established stable pattern of
angina may change sharply; it may by provoked by far less exercise than in the
past, or it may appear at rest. Angina in these forms is referred to as
"unstable angina" and needs prompt medical attention.
The term "unstable angina" is also
used when symptoms suggest a heart attack but hospital tests do not support that
diagnosis. For example, a patient may have typical but prolonged chest pain and
poor response to rest and medication, but there is no evidence of heart muscle
damage either on the electrocardiogram or in blood enzyme tests.
Are There Other Types of Angina?
There are two other forms of angina
pectoris. One, long recognized but quite rare, is called Prinzmetal's or variant
angina. This type is caused by vasospasm, a spasm that narrows the coronary
artery and lessens the flow of blood to the heart. The other is a recently
discovered type of angina called microvascular angina. Patients with this
condition experience chest pain but have no apparent coronary artery blockages.
Doctors have found that the pain results from poor function of tiny blood
vessels nourishing the heart as well as the arms and legs. Microvascular angina
can be treated with some of the same medications used for angina pectoris.