What is a Heart Attack?
Every
year, tens of thousands of Americans survive heart
attack, go back to work and enjoy a normal life.
You have every reason to be confident of a full
recovery. Your heart is healing and with each
passing day you’ll get stronger and more active.
The following questions and answers will help
you better understand what has happened to you
and how you get started on the road to recovery.
Why
did I have a heart attack?
Your heart muscle needs oxygen to survive.
A coronary attack (heart attack) occurs when the
blood flow that brings oxygen to the heart muscle
is severely reduced or cut off completely. This
happens because coronary arteries that
supply the heart with blood can slowly become
thicker and harder from a buildup of fat, cholesterol
and other substances that together are called
plaque. This slow process is known as atherosclerosis
. When a plaque in a heart artery breaks, a
blood clot forms around the plaque. This
blood clot can block the artery and shut off blood
flow to the heart muscle. When the heart muscle
is starved for oxygen and nutrients, it is called
ischemia . When damage or death of part of the
heart muscle occurs as a result of ischemia, it
is called a heart attack or myocardial
infarction (MI).
Why
didn’t I have any warning?
Atherosclerosis has no symptoms. One reason
there may be no warning signs is that sometimes
when a coronary artery becomes narrowed, other
nearby vessels that also bring blood to the heart
sometimes expand to help compensate. The network
of expanded vessels is called collateral
circulation and helps protect some people
from heart attacks by getting needed blood to
the heart. Collateral circulation can also develop
after a heart attack to help the heart muscle
recover.
Is
my heart permanently damaged?
When a heart attack occurs, the heart muscle
that has lost blood supply begins to die. The
amount of damage to the heart muscle depends on
the size of the area supplied by the blocked artery
and the time between injury and treatment. Damage
to the heart muscle from a heart attack heals
by forming scar tissue. It usually takes a month
to several weeks for your heart muscle to heal.
The length of time depends on the extent of your
injury and your own rate of healing. The heart
is a very tough organ. Even though a part of it
may have died, the rest keeps working. But because
your heart has been damaged, it is weaker and
can’t pump as much blood as usual. However, with
proper treatment and lifestyle
changes, further damage can be limited or prevented.
Will
I recover from my heart attack?
The answer is most likely yes. The heart muscle
begins to heal soon after a heart attack and usually
takes about eight weeks. Scar tissue will form
in the damaged area, and that scar tissue does
not contract or pump as well as healthy muscle
tissue. That means the heart can’t pump as well
as before. The degree of loss of function depends
on the size and location of the scar tissue. Most
heart attack survivors have some degree of
coronary artery disease (CAD) and will have
to make important lifestyle changes and possibly
take medication to prevent a future heart attack
and lead a full, productive life.
Is all chest pain a heart attack?
No. One very common type of chest pain is
called angina , or angina pectoris. It’s
a recurring discomfort that usually lasts only
a few minutes. Angina occurs when your heart muscle
doesn’t get the blood supply and oxygen that it
needs. The difference between angina and a heart
attack is that angina attacks don’t permanently
damage the heart muscle. Often angina occurs during
exercise or emotional stress when your heart rate
and blood pressure increase and your heart muscle
needs more oxygen.
What are the different medical terms for a
heart attack?
Myocardial infarction – The damaging or death
of an area of the heart muscle (myocardium) resulting
from a blocked blood supply to that area; medical
term for a heart attack.
Coronary
thrombosis – Formation of a clot in one of
the arteries that conduct blood to the heart muscle.
Also called coronary occlusion.
Coronary
occlusion – An obstruction of a coronary artery
that hinders blood flow to some part of the heart
muscle. A cause of heart attack.
Are there other causes of heart attack
besides blockage?
Sometimes a coronary artery temporarily contracts
or goes into spasm. When this happens the artery
narrows and blood flow to part of the heart muscle
decreases or stops. We're not sure what causes
a spasm. A spasm can occur in normal-appearing
blood vessels as well as in vessels partly blocked
by atherosclerosis. A severe spasm can cause a
heart attack.
Is a heart attack the same as cardiac arrest?
No. Heart attacks are caused by a blockage
that stops blood flow to the heart. Cardiac arrest
is caused when the heart’s electrical system malfunctions.
In cardiac arrest (also called sudden cardiac
death or SCD), death results when the heart suddenly
stops working properly. This is caused by abnormal,
or irregular, heart rhythms . This is when the
heart’s lower chambers suddenly start beating
chaotically and don’t pump blood. Death occurs
within minutes after the heart stops. SCD may
be reversed if CPR (cardiopulmonary resuscitation)
is performed and a defibrillator is used to shock
the heart and restore a normal heart rhythm
