Coronary artery disease (CAD) is the narrowing of the arteries
supply blood to the heart, called the coronary artery. This
occurs because of a build up of fatty deposits along the inner
wall of the artery. This process is known as atherosclerosis.
CAD is a progressive disease, which increases the risk of heart
attack and sudden death.
is going on in the body?
In order for the heart
to pump normally, the heart muscle needs a continuous supply
of oxygen-enriched blood. This blood is delivered by the coronary
arteries. Two main vessels branch out to supply blood to the
entire muscle of the heart. The heart needs more oxygen during
exercise and strenuous activity. It requires less when a person
is resting. When the arteries become blocked, less blood can
get through. The blockage can be small. In other cases, it completely
obstructs blood flow. Blockage can occur in one or many coronary
arteries. Small blockages may not always affect the heart's
performance. The person may not have symptoms until the the
heart demands a greater amount of oxygen-rich blood than the
arteries can supply. This commonly occurs during exercise or
other activity. The resulting pain is called stable angina.
If a blockage is large, angina pain can occur with little or
no activity, and is known as unstable angina . In this case,
the flow of blood to the heart is so limited that the person
cannot perform daily tasks without bringing on an angina attack.
When the blood flow to an area of the heart is completely blocked,
a heart attack occurs.
are the signs and symptoms of the disease?
of CAD vary widely. Also, a person's symptoms do not always
indicate the severity the condition. The classic indicator of
CAD is angina. This is characterized by chest pain that radiates
to the neck, jaw or left arm. It also includes shortness of
breath. The pain is often described as a crushing, burning or
squeezing sensation. Some people may have no symptoms at all
until they suffer a heart attack. Their physical exams may be
completely normal, as well.
are the causes and risks of the disease?
affects people of all races. It can be caused by a combination
of unhealthy lifestyle and genetics. Coronary risk factors that
increase the risk of CAD include:
high in sodium
Genetic factors that affect heart disease risk
are beyond a person's control. These include a strong family
The genetic tendency for CAD makes a person's health
habits particularly important. Avoiding lifestyle risks can
prevent or delay the development of CAD.
can be done to prevent the disease?
to unhealthy lifestyle habits can be reduced by:
a healthy diet
A healthy lifestyle may also help delay or prevent
the development of CAD in people with a genetic tendency toward
the disease. A person who is at high risk should strictly comply
with treatments to lower cholesterol
and blood pressure.
is the disease diagnosed?
A first step in diagnosing
the disease is to take the person's medical history. Important
factors to consider include:
and duration of angina
of coronary risk factors
Also useful is an electrocardiogram, or ECG.
This test may show indications of the effects of high blood
pressure, areas of the heart deprived of blood, or scarring
of the heart due to previous heart
attack. An ECG may be normal between attacks of angina.
Another type of test, a stress test, is basically
an ECG taken before, during and after exercise. It is designed
to bring on an attack of angina and record the changes that
occur in the heart on an ECG. Sometimes the person is injected
with a substance called thallium during the stress test. Special
pictures are then taken of the heart. The thallium scan can
reveal areas of the heart that are damaged.
The most reliable test for diagnosing CAD, however,
remains the coronary angiogram . In this procedure, a long and
very thin hollow tube or catheter is inserted into an artery
in the leg or arm. It is then advanced through the artery and
into the coronary artery. A dye is injected into the tube. Pictures
are taken as the dye is pumped into the coronary arteries. This
illuminates blockages. Other techniques that are being used
to help in the diagnosis CAD include stress echocardiograms
and new generations of CT
are the long-term effects?
CAD is a progressive
disease that can lead to heart attack and sudden death.
are the risks to others?
The genetic tendency for
the disease can be passed on from generation to generation.
Otherwise there is no risk to others.
are the treatments?
Treatment of CAD varies widely.
It must be tailored for each person. The goal of treatment is
to either reduce the amount of oxygen demanded by the heart
or increase the oxygen supply. Two types of heart medications
are commonly used for this purpose. The first reduces the work
the heart has to do and therefore its oxygen needs. The other
type relaxes the coronary arteries so more blood can get through
to the heart. Medications that lower blood pressure and cholesterol
are also very important. Other drugs such as aspirin are used
to reduce the risk of blood clots.
In addition to medication, controlling risk
factors such as poor diet and smoking is recommended for all
people with CAD.
If the disease is severe, a person may need
surgery or other procedures to alleviate the blockage in the
arteries. One such procedure is a less invasive technique is
called balloon angioplasty . A special balloon-tipped catheter
is threaded into the coronary artery. It is similar to the catheter
used to inject the dye when x-rays are taken of the arteries.
Once the catheter is positioned at the point of the blockage,
the balloon is then inflated to expand the narrowed area. The
goal is to improve blood flow through the artery. Another option
is heart bypass surgery to bypass the narrowed area. Blood flow
is routed around the blockage using a blood vessel borrowed
from another part of the body. This vessel is grafted to the
coronary artery beyond the narrowed area providing an alternate
route for blood flow to the heart. This procedure is commonly
called coronary artery bypass graft, or CABG. Multiple vessels
can be bypassed if more coronary artery is affected.
are the side effects of the treatments?
are associated side effects. These may include headache, dizziness
and upset stomach. Blood thinning medications may increase the
risk of bleeding and hemorrhage. Balloon angioplasty carries
the risk that the vessel may become blocked again. Sometimes
the angioplasty is not successful and CABG must be preformed
at that time. The risk of CABG includes, bleeding, infection
happens after treatment?
People who have surgery
or angioplasty are carefully watched to for bleeding, reocclusion
of the artery and a return to the normal structure and function
of the heart. Individuals are also helped to make needed lifestyle
changes. Also, people will start special cardiac rehabilitation
programs. It is important that individuals strictly adhere to
their treatment plans.
is the disease monitored?
People will need to
visit the healthcare provider regularly to have their medictaions
adjusted and their blood pressure and weight measured. Individuals
should report the return or worsening of symptoms to the providrer.
Periodic stress testing is required to make sure that there
is proper blood flow to the heart.
Eric Berlin, MD Source: Healthy Answers