|
|
Introduction
Myocardial infarction or heart attack is damage to the
heart caused by lack of oxygen to the heart muscle as
a result of coronary artery disease. The arteries that
supply blood to the heart itself are called the
coronary arteries. When the coronary arteries are
blocked or damaged, the flow of blood to the
myocardial muscles is interrupted. They become hypoxic
and infraction (death) occurs.
Causes
A heart attack is caused when one or more of the
coronary arteries that supply blood to heart become
completely blocked and blood to the heart muscle is
cut off. The blockage is usually caused by the
build-up of plaque over the years in the artery walls
or a blood clot in a coronary artery. If a plaque
breaks open, the body tries to fix it by forming a
clot around it. The clot can block the artery,
preventing the flow of blood and oxygen to the heart.
This process of plaque buildup in the coronary
arteries is called coronary artery disease, or CAD. In
many people, plaque begins to form in childhood and
gradually builds up over a lifetime. Plaque deposits
may limit blood flow to the heart and cause angina.
But too often, a heart attack is the first sign of
CAD.
Symptoms
The most common symptom of a heart attack is severe
chest pain. Many people describe the pain as
discomfort, pressure, squeezing, or heaviness in the
chest. Other symptoms include pain that spreads to the
shoulders, neck, or arms and chest discomfort
accompanied by lightheadedness, fainting, sweating,
nausea, or shortness of breath.
Treatment
Once a heart attack has been diagnosed, the doctor
may perform cardiopulmonary resuscitation when
necessary to start and keep the patient breathing and
the heart beating. The doctor will usually prescribe
clot-busting drugs and other artery opening treatments
that can stop a heart attack in progress and limit
damage to the heart muscle.
You may be given medicines, including:
Aspirin (if you have not already taken some) and other
medicines to prevent blood clots.
Medicines that break up blood clots (thrombolytics).
To work, these must be given within a few hours of the
start of the heart attack.
Medicines to decrease the heart's workload, ease pain,
and prevent abnormal heart rhythms, which can be
life-threatening.
|
