mon birth defects in the United States. Some con-
genital heart defects are life-threatening, such as
tetralogy of Fallot and transposition of the great
arteries (TGA), and require extensive surgical
reconstruction or HEART TRANSPLANTATION for the
infant to survive. Many congenital heart anom-
alies are correctable with surgery or treatable with
medications, allowing the child relatively normal
life experiences and life expectancy. Researchers
do not know the causes of many of these defects,
which arise early in embryonic development.
Though some of the most exciting technological
advances in modern medicine are those that
improve treatment for cardiovascular conditions
such as heart failure, health experts believe lifestyle
measures could prevent as much as 90 percent of
acquired cardiovascular disease. Cardiovascular
health depends on four key lifestyle factors:
- not smoking
- nutritious eating habits
- daily physical exercise
- maintaining healthy weight
These factors maintain the cardiovascular sys-
tem in optimal health. Yet despite the overwhelm-
ing evidence that these factors do in fact prevent
cardiovascular disease, two thirds of the US popu-
lation is overweight and three fourths do not get
the minimum recommended physical exercise.
Two lifestyle-related health conditions that
strongly influence cardiovascular disease are dia-
betes and OBESITY. Type 2 diabetes, the most com-
mon form of diabetes among American adults,
and obesity are closely linked. When these two
conditions coexist, some form of cardiovascular
disease is almost certainly present as well.
Traditions in Medical HistoryThe heart mystified ancient physicians. Though all
cultures recognized the relationship between the
heart and life itself, they differed vastly in their
interpretations of what that relationship was. The
Egyptians held the heart to be the base of intellect
and emotion in life and the measure of that life’s
worth upon a person’s passage to the afterworld.
Mesopotamian and Sumerian physicians used
MEDICINAL HERBS AND BOTANICALSto treat ailments
such as pounding of the pulse and heart weak-
ness—perhaps references to conditions contempo-
rary doctors might diagnose as PALPITATIONSand
HEART FAILURE.
Ancient Chinese physicians speculated that the
heart circulated all of the body’s vital substances,
including air, through a complex network of ves-
sels and passageways. Within the tenets of primi-
tive Chinese medicine the pulse spoke to the
physician, its rhythms and patterns presenting the
story of the body’s health and illnesses. A gifted
physician could interpret hundreds of details from
numerous pulse points. Intricate readings of the
pulse remain integral to TRADITIONALCHINESE MEDI-
CINE(TCM) as practiced today.
In Western medicine, Greek and Roman physi-
cians of antiquity postulated that the LIVERpro-
duced the body’s supply of blood from the food a
person ate. The veins carried the blood from the
liver to the other organs, which consumed it. The
arteries, in this scheme, arose from the heart
though carried air. The role of the heart itself was
somewhat ambiguous, with some physicians
believing the heart pulled air into the arteries
through pores in the skin and others that it had
nothing to do with any sort of circulation but
instead gave rise to emotions and thoughts.
The Greek physician GALEN (130–200) both
consolidated and expanded the understandings of
human anatomy and physiology of his time into
the principles and practices that became the foun-
dation of Western medicine for the ensuing 1,200
years. In Galen’s view, the veins delivered to the
heart blood the liver made, and the arteries car-
ried the air drawn into the body through pores in
the skin. Other pores between the chambers of the
heart, according to Galen, mixed the blood and
the air. Each beat of the heart then propelled this
mixture through the arteries to the organs of the
body. Though this schematic makes little sense in
the context of current knowledge, despite its fun-
damental inaccuracies it came fairly on target in
its projections of the body’s need for oxygen and
the role of the cardiovascular system to deliver it.
In Galen’s day, the concept was the ideal blend of
the many understandings and misunderstandings
about the functions of the body.6 The Cardiovascular System