The following webpage offers some of the best layperson information on heart
attacks and heart disease that I have yet come across on the web:
<http://webmd.lycos.com/content/dmk/dmk_article_40043>
In light of the fact that heart disease is so common in the West today, group
members would be well advised to read the entire article. This is how the
article begins:
<What Is a Heart Attack?
The heart is the human body's hardest working organ. Throughout life it
continuously pumps blood enriched with oxygen and vital nutrients through a
network of arteries to all parts of the body's tissues. It has its own
network of arteries, known as coronary arteries, that carry oxygen-rich blood
to the heart's muscular walls (the myocardium). If blood flow to the
myocardium is interrupted, an injury known as an infarct occurs, in other
words, a myocardial infarction, more commonly known as a heart attack.
In most cases of myocardial infarction, this restriction of blood flow to the
heart results from atherosclerosis, a process in which atheromas, layers of
yellowish plaque made up of cholesterol, fats, and other particles, are
deposited on the walls of arteries. The cholesterol plaques slowly thicken,
narrowing the arteries (a condition known as stenosis) until blood flow is
reduced. When the body's demand for oxygen exceeds its supply, ischemia, the
deficiency of oxygen in vital tissues, occurs. Prolonged periods of ischemia
can lead to tissue injury, which may be severe enough to cause a heart
attack.
Although atherosclerosis is ultimately responsible for almost all heart
attacks, the attack itself is triggered by a particular event. Most often a
blood clot, or thrombus, forms on the fatty plaque, completely blocking the
already narrowed coronary artery. In other cases, the plaque can rupture or
the artery can go into spasm; both of these events may also block the
coronary artery, depriving a portion of the heart muscle of its vital oxygen.
The severity of a heart attack depends upon the amount of the heart muscle
involved, how long the ischemia lasts, and the extent of the infarction.
....... >
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Dr Mel C Siff
Denver, USA
http://groups.yahoo.com/group/Supertraining/
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