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Untitled Essay Research Paper QUESTION What is

Untitled Essay, Research Paper

QUESTION: What is Angina? And

what is the cure?

================================

RESPONSE:

Angina refers to the pain arising from lack of adequate blood supply to the

heart muscle. Typically, it is a crushing pain behind the breastbone in the

center of the chest, brought on by exertion and relieved by rest. It may at

times radiate to or arise in the left arm, neck, jaw, left chest, or

back. It is frequently accompanied by sweating, palpitations of the

heart, and generally lasts a matter of minutes. Similar pain syndromes

may be caused by other diseases, including esophagitis, gall bladder

disease, ulcers, and others.

Diagnosis of angina begins with the recognition of the consistent

symptoms. Often an exercise test with radioactive thallium is performed

if the diagnosis is in question, and sometimes even a cardiac

catheterization is done if the outcome is felt necessary to make

management decisions. This is a complex area which requires careful

judgment by physician and patient.

Angina is a manifestation of coronary artery disease, the same

disease leading to heart attacks. Coronary artery diseas refers to

those syndromes caused by blockage to the flow of blood in those

arteries supplying the heart muscle itself, i.e., the coronary arteries.

Like any other organ, the heart requires a steady flow of oxygen and

nutrients to provide energy for rmovement, and to maintain the delicate

balance of chemicals which allow for the careful electrical rhythm

control of the heart beat. Unlike some other organs, the heart can

survive only a matter of minutes without these nutrients, and the rest

of the body can survive only minutes without the heart–thus the

critical nature of these syndromes.

Causes of blockage range from congenital tissue strands within or

over the arteries to spasms of the muscular coat of the arteries

themselves. By far the most common cause, however, is the deposition of

plaques of cholesterol, platelets and other substances within the

arterial walls. Sometimes the buildup is very gradual, but in other

cases the buildup is suddenly increased as a chunk of matter breaks off

and suddenly blocks the already narrowed opening.

Certain factors seem to favor the buildup of these plaques. A strong

family history of heart attacks is a definite risk factor, reflecting

some metabolic derangement in either cholesterol handling or some other

factor. Being male, for reasons probably related to the protective

effects of some female hormones, is also a relative risk. Cigarette

smoking and high blood pressure are definite risks, both reversible in

most cases. Risk also increases with age. Elevated blood cholesterol

levels (both total and low density types) are risks, whereas the high

density cholesterol level is a risk only if it is reduced. Possible,

but less well-defined factors include certain intense and hostile or

time-pressured personality types (so-called type A), inactive lifestyle,

and high cholesterol diets.

Medications are increasingly effective for symptom control, as well

as prevention of complications. The oldest and most common agents are

the nitrates, derivatives of nitroglycerine. They include

nitroglycerine, isosorbide, and similar agents. Newer forms include

long acting oral agents, plus skin patches which release a small amount

through the skin into the bloodstream over a full day. They act by

reducing the burden of blood returning to the heart from the veins and

also by dilating the coronary arteries themselves. Nitrates are highly

effective for relief and prevention of angina, and sometimes for

limiting the size of a heart attack. Used both for treatment of

symptoms as well as prevention of anticipated symptoms, nitrates are

considered by many to be the mainstay of medical therapy for angina.

The second group of drugs are called "beta blockers" for their

ability to block the activity of the beta receptors of the nervous

system. These receptors cause actions such as blood pressure elevation,

rapid heart rate, and forceful heart contractions. When these actions

are reduced, the heart needs less blood, and thus angina may be reduced.

The newest group of drugs for angina is called the calcium channel

blockers. Calcium channels refer to the areas of the membranes of heart

and other cells where calcium flows in and out, reacting with other

chemicals to modulate the force and rate of contractions. In the heart,

they can reduce the force and rate of contractions and electrical

excitability, thereby having a calming effect on the heart. Although

their final place in heart disease remains to be seen, they promise to

play an increasingly important role.

When me




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