Chest pain or pressure,
tightness, squeezing, burning, aching, or heaviness in the chest,
lasting longer than 10 minutes. The pain or discomfort is usually
located in the center of the chest just under the breastbone
and may radiate down the arm (especially the left arm), up into
the neck, or along the jaw line.
or a feeling of impending doom.
occur with a silent heart attack.
When To Call Your Doctor
an ambulance if you experience crushing chest pain with or without
nausea, vomiting, profuse sweating, breathlessness, weakness,
or intense feelings of dread.
an ambulance if chest pain from previously diagnosed angina does
not subside after 10 to 15 minutes.
an ambulance the first time you experience intense chest pain.
What Is It?
A heart attack, also called a myocardial infarction,
is a medical emergency that occurs when a portion of the heart
is deprived of oxygen because of blockage of one of the coronary
arteries, which supply the heart muscle with blood. Lack of oxygen
causes characteristic chest pain and death of heart muscle tissue.
Heart attacks are more likely to occur when arteries
have already been substantially narrowed by years of coronary
heart disease. Plaquecomposed of cholesterol-rich fatty
deposits, collagen and other proteins, and excess smooth muscle
cellsbuilds up in the arterial walls, a process known as
atherosclerosis. Arterial walls thicken and narrow, inhibiting
the flow of blood to the heart. When arterial walls have been
roughened by plaque deposits, it becomes much easier for blood
clots to form along the surface of the plaque. If the clots grow,
or if they detach from their place of origin and are carried
along to a narrower section of artery, they may block a coronary
artery completely, causing a heart attack. Arteries may also
narrow suddenly as a result of an arterial spasm.
One third of all heart attacks occur with no prior
warning signs. In the remainder, attacks of chest pain (angina)
brought on by stress or exertion occur periodically for months
or years prior to a heart attack. In some cases a mild heart
attack produces no symptomsa so-called silent heart attack.
Prompt emergency medical attention is crucial:
If treatment is received within a few hours of the onset of a
heart attack, chances for survival are good. Improved treatment
methodsincluding the administration of thrombolytic (clot
dissolving) drugs and angioplasty (inflation of a tiny balloon
at the site of the blockage to widen the artery and permit the
flow of blood through the artery)have led to a steady decrease
in the death rate from heart attacks. However, the best treatment
remains prevention. The process of atherosclerosis may be halted
or even reversed with fairly simple measures, and the risk of
heart attack can thus be reduced.
What Causes It?
that block a coronary artery are the most common cause of heart
attacks. Clots develop on plaque in a coronary artery. Pieces
of a clot may also be carried along the coronary artery and cause
arteries due to atherosclerosis underlie the development of a
high blood pressure, high blood cholesterol levels, a diet rich
in saturated fat (especially animal fat), obesity, lack of exercise,
and diabetes all promote atherosclerosis and thus increase the
risk of heart attack.
A family history
of early or premature heart attacks (before the age of 55 in
men and 65 in women) increases the risk of heart attack.
Men have a
significantly higher risk of heart attack than premenopausal
women. But the risk for postmenopausal women approaches that
of men as estrogen production decreases with menopause.
with age: Heart attacks are most common after age 65.
A spasm of
the muscles of the arterial walls may cause a heart attack by
narrowing an artery. Spasms may be triggered by smoking, extreme
emotional stress, or exposure to very cold air or water.
Abuse of cocaine
or amphetamines may cause a sudden heart attack even in those
with no signs of heart disease.
such as shoveling snow or carrying heavy objects up stairs, and
severe emotional stress may trigger a heart attack.
a heart attack increases the risk of future heart attacks.
smoke. Your doctor may recommend methods for quitting, including
nicotine replacement therapy.
Eat a diet
low in fat, cholesterol, and salt.
See your doctor
regularly for blood pressure and cholesterol monitoring.
Pursue a program
of moderate, regular aerobic exercise. People over age 50 who
have led a sedentary lifestyle should check with a doctor before
beginning an exercise program.
if you are overweight.
may advise you to take a low dose of aspirin regularly. Aspirin
reduces the tendency for the blood to clot, thereby decreasing
the risk of heart attack. However, such a regimen should only
be initiated under a doctors recommendation.
and physical examination are needed. Diagnosis will often be
made immediately by a doctor or emergency response technician.
(ECG) will be performed. This test measures changes in the electrical
activity of the heart that result from abnormalities in the flow
measure enzymes that are released from the damaged heart muscle
into the bloodstream.
(using a tiny catheter inserted into an artery in the groin and
threaded up the artery to the heart) is performed to locate the
arterial blockage prior to angioplasty or bypass surgery. A contrast
material is then injected from the end of the catheter into the
coronary arteries, and a series of x-rays is taken.
It is advised
to chew on an aspirin at the onset of the symptoms of a heart
attack. It may help break up the blood clot.
and immediate hospitalization is necessary.
If the heart
has stopped beating, it must be restarted immediately by cardiopulmonary
resuscitation (CPR) or by a device known as an electrical defibrillator.
or clot-dissolving, drugs such as tissue plasminogen activator
(tPA), streptokinase, or urokinase may be injected immediately
to dissolve the arterial blockage. This technique is most effective
within three hours of the onset of a heart attack.
such as morphine or meperidine are administered to relieve pain.
may be given to reduce the oxygen demands of the heart and to
lower blood pressure.
drugs such as beta-blockers, ACE inhibitors, or calcium channel
blockers may also be administered to lower blood pressure and
to reduce the hearts oxygen demand. The effect of these
drugs may be enhanced by diuretics.
be administered through nasal tubes.
such as heparin, aspirin, or warfarin may be administered to
reduce the risk of further blood clots.
may be prescribed in some cases to strengthen heart muscle contractions.
(In the United States, digoxin is the most commonly prescribed
type of digitalis.)
dobutamine may be administered to increase blood flow to the
heart and strengthen the heartbeat.
may be opened or widened by percutaneous transluminal coronary
angioplasty (PTCA). In this procedure a small balloon is inserted
into an artery in the groin, guided with a catheter to the narrowed
point in the coronary artery, and then inflated. This compresses
the plaque, widens the passageway, and improves blood flow.
surgery may be performed to restore adequate blood flow to the
heart muscle. A mammary artery or a vein from the leg is grafted
onto the narrowed coronary artery to circumvent the blocked portion.
implants such as a pacemaker or a defibrillator may be attached
to the heart to maintain strong, regular contractions of the
A heart transplant
may be advised in severe cases when heart tissue has been badly
damaged. The survival rate for heart transplant is 85 percent
after one year and 65 percent after five years.
follow prevention tips to reduce the risk of another heart attack.
local chapter of the American
Heart Association for information about support groups.
Hopkins Symptoms and Remedies, the complete home medical
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