The Changing Heart
At one time, nothing could be done about heart disease. As
someone clutched their heart and gasped, we could do nothing
but look on in pain. As we learned more about the heart, we
developed drugs and learned how to cut open the body and
partially repair the heart. Today, the death rate for all
heart-related diseases is 45 percent of what it was in 1963.
Many claim that drugs and surgery are the reasons for
this.
But, if this is so, why is "progress" slowing down?
According to the Harvard Health Letter (January 1998),
there appears to be a slight rise in the incidences of stroke
and kidney disease, and a leveling of the death rate from
heart disease among U.S. adults. In other words, perhaps the
well-established paradigm - drugs and surgery - is not the
best answer. Perhaps it is time to review our past and see
what we can learn. Perhaps it is time to change the
paradigm.
History
The
history of the heart and its diseases, like all medical
history, is a history of ideas: an initial idea, reinforcement
of the idea, rebukes to the challenges, and, perhaps, a new
idea.
One of he first ideas was put forth by Erasistratus of
Alexandria, who dissected animals and humans (probably
Egyptian mummies) 2,300 years ago. He discovered the veins,
arteries, and nerves, and postulated that the heart is nothing
more than their junction and that the arteries contain not
blood, but air, spirit, or soul (called pneuma). This entered
the body through the nose.
Parts of this idea were reconfirmed, but many more were
challenged and disproved. The great physician of the Roman
Empire, Galen, confirmed that veins contain blood, but did
away with the idea of pneuma. He saw that the heart is more
than a "circulation junction" and that blood flows throughout
the body, but believed it ebbs and flows with the heartbeat.
Galen was such a great influence upon the medical world that
his ideas became "medicine" . They were codified, made rigid,
and acknowledged as the "limit" to medical information.
| Cardiovascular
diseases (CVD) - which encompass events such as heart
attack, stroke, angina pectoris, atherosclerosis and
arteriosclerosis, and high blood pressure - are the No.
1 killer in North America. In the United States,
somebody dies from heart disease every 33 seconds, and
from a heart attack every minute. In Canada, in 1992,
CVD accounted for 38 percent of all
deaths. |
The Renaissance
saw the first revolt against the dogmatic rules that Galen's
ideas had become. The Swiss physician Paracelsus rejected much
of Galen's thought and spoke forcefully against the tendency
to accept Galen's ideas as truth:
"Who does not know that doctors make terrible mistakes,
greatly to the harm of their patients? Who does not know that
this is because they cling too anxiously to the teachings of
Hippocrates, Galen . . . "
For daring to challenge the status quo, he was condemned to
a nomadic existence, traveling from town to town.
Andreas Vesalius, born in 1514, continued the challenge to
the medical status quo. He compiled the complete anatomy of
the human body and, in doing so, discovered and exposed more
than 200 errors by Galen. In undermining much of this medical
authority, he became controversial at best, and a pariah at
worst. He was attacked by many of the pro-Galen forces and
retired from academic pursuits embittered and
disillusioned.
William Harvey, known as the grandfather of cardiology,
drove a stake into the heart of the old school of cardiology.
He understood that the heart and blood are elements within a
closed system, described correctly how blood flows through the
heart, and saw that the heart is the engine that pumps blood.
He saw that the heart, lungs, and blood vessels are
interdependent and that what we call heart disease may
actually originate somewhere other than the heart, especially
in the arterial systems.
A common thread that runs throughout this brief history
(and, as we shall see, continues today) is that ideas become a
rigid status quo (often through no fault of the ideas'
originators) and that when they are challenged, the challenger
is repudiated, discredited, and often driven out. It is
reported that even Harvey, after publishing his ideas,
suffered an immediate decline in number of patients because of
his "strange theories."
"Strange theories" . .
.
The notion that new ideas are "strange
theories" continues in modern times. In the '60s and '70s,
Nathan Pritkin was persecuted as a quack and incompetent rebel
when he concluded that most heart disease is reversible
through a combination of diet, exercise, and stress
management. The medical profession was relentless in its
criticism, accusing him of giving patients false hope and
defrauding them by selling them his program of lifestyle
changes ot prevent heart disease.
The 1960s saw another alternative opinion shot down by the
medical community. Kilmer S. McCully, M.D., then a professor
of pathology at Harvard University Medical School, went
against the "killer cholesterol" tide when his studies pointed
to an amino acid, homocysteine, as a major cause of heart
disease.
McCully had come across research that noted that some
mentally retarded children were dying of heart disease before
reaching puberty, and the reason was due to high blood levels
of homocysteine. In 1969, after studying this issue, McCully
proposed that many Americans suffer from cardiovascular
disease due to high homocysteine levels, not cholesterol. More
radically, he proposed that all one has to do is take
B-complex vitamins to solve this problem.
| McCully's
Theory |
| One drawback to
the "cholesterol is king" theory of cardiovascular
disease (CVD) is that many people with no risk factors
suffer from heart problems.
Indeed, an article in the June 26, 1996, issue of
the Journal of the American Medical Association
notes that the traditional CVD risk factors (age,
genetics, gender, smoking, blood pressure, cholesterol,
sedentary lifestyle, diabetes, weight, stress) only
explain about 50 percent of all CVD. The amino acid
homocysteine may be the reason.
Homocysteine is formed when the body breaks down
protein, especially the protein found in meat. Meat
protein contains the essential amino acid methionine,
and when methionine is digested, it produces
homocysteine. According to McCully's theory, if
homocysteine levels increase, the result is the buildup
of plaque, which, of course, may lead to
atherosclerosis, heart attacks, strokes, and death.
Homocysteine builds up if we eat too much meat or do
not get sufficient amounts of vitamins B6 and B12 and
folic acid. These three vitamins are integral in the
process of recycling and excreting homocysteine. If we
do not have sufficient amounts of these vitamins,
homocysteine levels rise. |
For the next few years, McCully struggled against the
cholesterol tide and in 1978, had to leave Harvard. In his
book, The Homocysteine Revolution, he notes that hew
was told he had "failed to prove his theory."
Become
Mainstream
Pritkin and McCully, like Vesalius
and Harvey before them, were proven correct. In the late '80s,
Surgeon General C. Everett Koop took the bold step of
reversing decades of medical thought when he declared that 75
percent of the deaths in America are caused by lifestyle
decisions on diet, smoking, and consumption of alcohol. Today,
the National Heart Association publishes a list of dietary
recommendations that echo Pritkin's earlier conclusions.
McCully was also vindicated. Articles on homocysteine began
reappearing and, in 1995, studies in the Journal of the
American Medical Association reported that homocysteine is
a major risk factor in CVD. Today, homocysteine is considered
an independent risk factor - it is not influenced by other
factors, such as smoking, cholesterol, and physical activity.
It is also acknowledged that adequate amounts of vitamins B12
and B6 and folic acid can reduce high homocysteine levels and
lower the risk of CVD.
Today, there is more and more emphasis on lifestyle as the
key to cardiovascular health. Virtually all heart
organizations acknowledge that diet and exercise are keys in
preventing heart disease and recommend a diet that is low in
total fat, saturated fat, and cholesterol and rich in fruits,
vegetables, and fiber.
The paradigm
changes
The paradigm underlying these new ideas
is that we are responsible for our health. If bad lifestyle
decisions are responsible for 75 percent of the deaths in
America; if most heart disease is reversible through a
combination of diet, exercise, and stress management; if
nutrition combats high homocysteine and cholesterol levels, it
means that we have it in our power to control our health
destiny. We do not have to wait until the crisis and then rush
to the doctor or hospital; we can take steps to lower our risk
of, and prevent, CVD.
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