- Fear can kill.
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- People died of fear during the Los Angeles
earthquake.
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- Scientists are launching a study to try
to predict which people are in danger of dying from fright.
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- According to New Scientist magazine,
researchers are now convinced that there is some truth in the old saying
"I was scared to death".
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- In some cases, the body's own fight-or-flight
response to danger appears to backfire and stop the heart completely. It
may also trigger fatal heart attacks.
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- Doctors might be able to prevent this
type of heart attack if they can identify the people at risk.
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- Dr James Muller, of Kentucky University,
in Lexington, examines the causes of heart attacks.
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- Next month he begins a study of 2,000
people who have cardiac defibrillators implanted in their chests because
they have already suffered one near-fatal heart attack.
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- He hopes to get a clearer picture of
what types of physical and emotional stresses can induce abnormal heart
rhythms.
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- Earth-shattering proof
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- Compelling evidence for the theory that
fear can kill was provided by a study of deaths following the 1994 Los
Angeles earthquake.
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- Dr Robert Kloner, a cardiologist at the
Good Samaritan Hospital in Los Angeles, reviewed the records of the Los
Angeles county coroner's department for the week before the earthquake,
the day of the earthquake and corresponding control periods in 1991, 1992
and 1993.
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- His team found that on the day of the
quake, the coroner recorded five times more sudden cardiac deaths than
would ordinarily be expected.
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- This was nothing to do with people physically
exerting themselves as they dug themselves out of the rubble, they said.
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- Dr Kloner said: "The typical story
was that a patient clutched his chest, described chest pain, and dropped
over dead."
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- A similar phenomenon occurred when the
Iraqis launched missile strikes on Israel during the Gulf War in 1991.
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- During the early hours of 18 January,
when the first attack occurred, 147 deaths were recorded.
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- Records for previous years showed that
under normal circumstances only 93 deaths would have been expected during
this time.
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- Most of these deaths were from heart
attacks, and the increased mortality was limited to the first day of missiles.
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- Most people who die from fear have a
long-standing condition - such as cholesterol problems - that puts them
at additional risk.
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- But, in a tiny minority of cases, a healthy
person may become so terrified that the brain triggers the release of a
mix of chemicals so potent that it induces a massive influx of calcium
into the heart cells.
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- This causes the heart to contract so
fiercely that it never relaxes again.
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- Fight or flight
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- Terror, or any extreme emotional response,
stimulates the fight-or-flight response.
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- The brain's hypothalamus tells the adrenal
glands to start pumping hormones such as adrenaline and noradrenaline -
also known as catecholamines - into the bloodstream.
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- The effect is to:
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- Constrict blood vessels; Increase the
ability of the blood to coagulate thereby reduce bleeding; Dilate the pupils
for better vision; Increase the heart rate; Divert blood from the gastrointestinal
tract to the muscles.
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- The brain also stimulates organs by causing
nerves to secrete catecholamines directly into them - thus triggering the
deadly contraction.
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- It appears the more common types of heart
attacks can also be triggered by fear.
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- The release of hormones causes arteries
to clamp down, for example, and platelets start to aggregate in readiness
for clotting.
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- Blood rushing through narrowed vessels
also generates shear forces against cholesterol plaques stuck to blood
vessel walls.
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- If a plaque breaks, the debris can cause
a clot and block blood flow to the heart muscle.
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