Angina Pectoris

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Angina Pectoris

ANGINA PECTORIS

Submitted by: Course: SBI OAO To: Date:


CONTENTS


3 Introduction
4 The Human Heart
5 Symptoms of Coronary Heart Disease
5 Heart Attack
5 Sudden Death
5 Angina
6 Angina Pectoris
6 Signs and Symptoms
7 Different Forms of Angina
8 Causes of Angina
9 Atherosclerosis
9 Plaque
10 Lipoproteins
10 Lipoproteins and Atheroma
11 Risk Factors
11 Family History
11 Diabetes
11 Hypertension
11 Cholesterol
12 Smoking
12 Multiple Risk Factors
13 Diagnosis
14 Drug Treatment
14 Nitrates
14 Beta-blockers
15 Calcium antagonists
15 Other Medications
16 Surgery
16 Coronary Bypass Surgery
17 Angioplasty
18 Self-Help
20 Type-A Behaviour Pattern
21 Cardiac Rehab Program
22 Conclusion
23 Diagrams and Charts
26 Bibliography

INTRODUCTION

In today's society, people are gaining medical knowledge at quite a fast
pace. Treatments, cures, and vaccines for various diseases and disorders are
being developed constantly, and yet, coronary heart disease remains the number
one killer in the world.

The media today concentrates intensely on drug and alcohol abuse, homicides,
AIDS and so on. What a lot of people are not realizing is that coronary heart
disease actually accounts for about 80% of all sudden deaths. In fact, the
number of deaths from heart disease approximately equals to the number of deaths
from cancer, accidents, chronic lung disease, pneumonia and influenza, and
others, COMBINED.

One of the symptoms of coronary heart disease is angina pectoris.
Unfortunately, a lot of people do not take it seriously, and thus not realizing
that it may lead to other complications, and even death.

THE HUMAN HEART

In order to understand angina, one must know about our own heart. The human
heart is a powerful muscle in the body which is worked the hardest. A double
pump system, the heart consists of two pumps side by side, which pump blood to
all parts of the body. Its steady beating maintains the flow of blood through
the body day and night, year after year, non-stop from birth until death.

The heart is a hollow, muscular organ slightly bigger than a person's
clenched fist. It is located in the centre of the chest, under the breastbone
above the sternum, but it is slanted slightly to the left, giving people the
impression that their heart is on the left side of their chest.

The heart is divided into two halves, which are further divided into four
chambers: the left atrium and ventricle, and the right atrium and ventricle.
Each chamber on one side is separated from the other by a valve, and it is the
closure of these valves that produce the "lubb-dubb" sound so familiar to us.
(see Fig. 1 - The Structure of the Heart)

Like any other organs in our body, the heart needs a supply of blood and
oxygen, and coronary arteries supply them. There are two main coronary arteries,
the left coronary artery, and the right coronary artery. They branch off the
main artery of the body, the aorta. The right coronary artery circles the right
side and goes to the back of the heart. The left coronary artery further divides
into the left circumflex and the left anterior descending artery. These two left
arteries feed the front and the left side of the heart. The division of the left
coronary artery is the reason why doctors usually refer to three main coronary
arteries. (Fig. 2 - Coronary Arteries)SYMPTOMS OF CORONARY HEART DISEASE


There are three main symptoms of coronary heart disease: Heart Attack,
Sudden Death, and Angina.

Heart Attack

Heart attack occurs when a blood clot suddenly and completely blocks a
diseased coronary artery, resulting in the death of the heart muscle cells
supplied by that artery. Coronary and Coronary Thrombosis2 are terms that can
refer to a heart attack. Another term, Acute myocardial infarction2, means death
of heart muscle due to an inadequate blood supply.

Sudden Death

Sudden death occurs due to cardiac arrest. Cardiac arrest may be the first
symptom of coronary artery disease and may occur without any symptoms or warning
signs. Other causes of sudden deaths include drowning, suffocation,
electrocution, drug overdose, trauma (such as automobile accidents), and stroke.
Drowning, suffocation, and drug overdose usually cause respiratory arrest which
in turn cause cardiac arrest. Trauma may cause sudden death by severe injury to
the heart or brain, or by severe blood loss. Stroke causes damage to the brain
which can cause respiratory arrest and/or cardiac arrest.

Angina

People with coronary artery disease, whether or not they have had a heart
attack, may experience intermittent chest pain, pressure, or discomforts. This
situation is known as angina pectoris. It occurs when the narrowing of the
coronary arteries temporarily prevents an adequate supply of blood and oxygen to
meet the demands of working heart muscles.ANGINA PECTORIS

Angina Pectoris (from angina meaning strangling, and pectoris meaning
breast) is commonly known simply as angina and means pain in the chest. The term
"angina" was first used during a lecture in 1768 by Dr. William Heberden. The
word was not intended to indicate "pain," but rather "strangling," with a
secondary sensation of fear.

Victims suffering from angina may experience pressure, discomfort, or a
squeezing sensation in the centre of the chest behind the breastbone. The pain
may radiate to the arms, the neck, even the upper back, and the pain may come
and go. It occurs when the heart is not receiving enough oxygen to meet an
increased demand.

Angina, as mentioned before, is only temporarily, and it does not cause any
permanent damage to the heart muscle. The underlying coronary heart disease,
however, continues to progress unless actions are taken to prevent it from
becoming worse.

Signs and Symptoms

Angina does not necessarily involve pain. The feeling varies from
individuals. In fact, some people described it as "chest pressure," "chest
distress," "heaviness," "burning feeling," "constriction," "tightness," and many
more. A person with angina may feel discomforts that fit one or several of the
following descriptions:

- Mild, vague discomfort in the centre of the chest, which
may radiate to the left shoulder or arm - Dull ache, pins and
needles, heaviness or pains in the
arms, usually more severe in the left arm - Pain that feels like
severe indigestion - Heaviness, tightness, fullness, dull ache, intense

pressure, a burning, vice-like, constriction, squeezing
sensation in the chest, throat or upper abdomen - Extreme tiredness,
exhaustion of a feeling of collapse - Shortness of breath, choking
sensation - A sense of foreboding or impending death accompanying
chest discomfort - Pains in the jaw, gums, teeth, throat or ear lobe
- Pains in the back or between the shoulder blades

Angina can be so severe that a person may feel frightened, or so mild that
it might be ignored. Angina attacks are usually short, from one or two minutes
to a maximum of about four to five. It usually goes away with rest, within a
couple of minutes, or ten minutes at the most.

Different Forms of Angina

There are several known forms of angina. Brief pain that comes on exertion
and leave fairly quickly on rest is known as stable angina. When angina pain
occurs during rest, it is called unstable angina. The symptoms are usually
severe and the coronary arteries are badly narrowed. If a person suffers from
unstable angina, there is a higher risk for that person to develop heart attacks.
The pain may come up to 20 times a day, and it can wake a person up, especially
after a disturbing dream.

Another type of angina is called atypical or variant angina. In this type
of angina, pain occurs only when a person is resting or asleep rather than from
exertion. It is thought to be the result of coronary artery spasm, a sort of
cramp that narrows the arteries.

Causes of Angina

The main cause of angina is the narrowing of the coronary arteries. In a
normal person, the inner walls of the coronary arteries are smooth and elastic,
allowing them to constrict and expand. This flexibility permits varying amounts
of oxygenated blood, appropriate to the demand at the time, to flow through the
coronary arteries. As a person grows older, fatty deposits will accumulate on
the artery walls, especially if the linings of the arteries are damaged due to
cigarette smoking or high blood pressure.

As more and more fatty materials build up, they form plaques which causes
the arteries to narrow and thus restricting the flow of blood. This process is
known as atherosclerosis. However, angina usually does not occur until about
two-thirds of the artery's diameter is blocked. Besides atherosclerosis, there
are other heart conditions resulting in the starvation of oxygen of the heart,
which also causes angina.

The nerve factor - The arteries are supplied with nerves, which allow them
to be controlled directly by the brain, especially the hypothalamus - an area at
the centre of the brain which regulates the emotions. The brain controls the
expanding and narrowing of the arteries when necessary. The pressures of modern
life: aggression, hostility, never-ending deadlines, remorseless, competition,
unrest, insecurity and so on, can trigger this control mechanism. When you
become emotional, the chemicals that are released, such as adrenaline,
noradrenaline, and serotonin, can cause a further constriction of the coronary
arteries. The pituitary gland, a small gland at the base of the brain, under the
control of the hypothalamus, can signal the adrenal glands to increase the
production of stress hormones such as cortisol and adrenaline even further.

Coronary spasm - Sudden constrictions of the muscle layer in an artery can
cause platelets to stick together, temporarily restricting the flow of flow.
This is known as coronary spasm. Platelets are minute particles in the blood,
which play an essential role both in the clotting process and in repairing any
damaged arterial walls. They tend to clump together more easily when the blood
is full of chemicals released during arousal, such as cortisol and others.

Coronary spasm causes the platelets to stick together and to the wall of
the artery, while substances released by the platelets as they stick together
further constrict the blood vessels. If the artery is already narrowed, this can
have a devastating effect as it drastically reduces the blood flow. (Fig. 3 -
Spasm in a coronary artery)

When people are very tense, they usually overbreathe or hold their breath
altogether. Shallow, irregular but rapid breathing washes out carbon dioxide
from the system and the blood will become over-oxygenated. One might think that
the more oxygen in the blood the better, but overloaded blood actually does not
give up oxygen as easily, therefore the amount of oxygen available to the heart
is reduced. Carbon dioxide is present in the blood in the form of carbonic acid,
when there is a loss in carbonic acid, the blood becomes more basic, or alkaline,
which leads to spasm of blood vessels, almost certainly in the brain but also in
the heart.

ATHEROSCLEROSIS

The coronary arteries may be clogged with atherosclerotic plaques, thus
narrowing the diameter. Plaques are usually collections of connection tissue,
fats, and smooth muscle cells. The plaque project into the lumen, the passageway
of the artery, and interfere with the flow of blood. In a normal artery, the
smooth muscle cells are in the middle layer of the arterial wall; in
atherosclerosis they migrate into the inner layer. The reason behind their
migration could hold the answers to explain the existence of atherosclerosis.
Two theories have been developed for the cause of atherosclerosis.

The first theory was suggested by German pathologist Rudolf Virchow over
100 years ago. He proposed that the passage of fatty material into the arterial
wall is the initial cause of atherosclerosis. The fatty material, especially
cholesterol, acts as an irritant, and the arterial wall respond with an
outpouring of cells, creating atherosclerotic plaque.

The second theory was developed by Austrian pathologist Karl von Rokitansky
in 1852. He suggested that atherosclerotic plaques are aftereffects of blood-
clot organization (thrombosis). The clot adheres to the intima and is gradually
converted to a mass of tissue, which evolves into a plaque.

There are evidences to support the latter theory. It has been found that
platelets and fibrin (a protein, the final product in thrombosis) are often
found in atherosclerotic plaques, also found are cholesterol crystals and cells
which are rich in lipid. The evidence suggests that thrombosis may play a role
in atherosclerosis, and in the development of the more complicated
atherosclerotic plaque. Though thrombosis may be important in initiating the
plaque, an elevated blood lipid level may accelerate arterial narrowing.

Plaque

Inside the plaque is a yellow, porridge-like substance, consisting of blood
lipids, cholesterol and triglycerides. These lipids are found in the bloodstream,
they combine with specific proteins to form lipoproteins. All lipoprotein
particles contain cholesterol, triglycerides, phospholipids, and proteins, but
the proportion varies in different particles.Lipoproteins

Lipoproteins all vary in size. The largest lipoproteins are called
Chylomicra, and consist mostly of triglycerides. The next in size are the pre-
beta-lipoproteins, then the beta lipoproteins. As their size decreases, so do
their concentration of triglycerides, but the smaller they are, the more
cholesterol they contain. Pre-beta-lipoproteins are also known as low density
lipoproteins (LDL), and beta lipoproteins are also called very low density
lipoproteins (VLDL). They are most significant in the development of atheroma.
The smallest lipoprotein particles, the alpha lipoproteins, contain a low
concentration of cholesterol and triglycerides, but a high level of proteins,
and are also known as high density lipoproteins (HDL). They are thought to be
protective against the development of atherosclerotic plaque. In fact, they are
transported to the liver rather than to the blood vessels.

Lipoproteins and Atheroma
Continues for 13 more pages >>