New lining grows in the artery within a
few weeks of surgery. When narrowing is
widespread, arterial reconstructive sur-
gerymay have to be performed.
endemicA term applied to a disease or
disorder that is constantly present in a
particular region or in a specific group
of people. AIDS, for example, is endem-
ic in central Africa. (See also epidemic).
endocarditisInflammation of the endo-
cardium (the membrane that lines the
inside of the heart), particularly of the
heart valves. Endocarditis is most often
due to infection with bacteria, fungi, or
other microorganisms, which may be
introduced into the bloodstream during
surgery or by intravenousinjection with
dirty needles. People whose endocardi-
um has previously been damaged by
disease are particularly vulnerable to
endocarditis, as are intravenous drug
users and people whose immune sys-
tem is suppressed. Endocarditis is also
a rare feature of some types of cancer.
Endocarditis may be either subacuteor
acute. In the subacute form, symptoms
are general and nonspecific, although
serious damage may be caused to a
heart valve; the sufferer may complain
of fatigue, feverishness, and vague
aches and pains. On physical examina-
tion, the only evident abnormality may
be a heart murmur. Acute endocarditis,
which occurs less frequently, comes on
suddenly, and causes severe chills, high
fever, shortness of breath, and rapid or
irregular heartbeat. The infection pro-
gresses quickly and may destroy the
heart valves, leading to heart failure.
Endocarditis is diagnosed by physical
examination and analysis of blood sam-
ples. Tests on the heart may include
ECG, echocardiography, and angiogra-
phy. Treatment is with high doses of
antibiotic drugs, which are usually given
intravenously. Heart-valve surgerymay
be needed to replace a damaged valve.
endocrine glandA gland that secretes
hormonesdirectly into the bloodstream
rather than through a duct. Examples
include the thyroid gland, pituitary gland,
ovaries, testes, and adrenal glands. (See
also exocrine gland.)
endocrine systemThe collection of
glands around the body that producehormones. These glands include the
thyroid gland, pancreas, testes, ovaries,
and adrenal glands.Their hormones are
responsible for numerous bodily pro-
cesses, including growth, metabolism,
sexual development and function, and
response to stress. Any increase or
decrease in the production of a specific
hormone interferes with the process it
controls. To prevent under- or overpro-
duction, hormone secretion from many
endocrine glands is regulated by the
pituitary gland, which is in turn influ-
enced by the hypothalamusin the brain
according to a feedbackmechanism.
endocrinologyThe study of the endo-
crine system, including the investigation
and treatment of its disorders.
endodonticsThe branch of dentistry
concerned with the causes, prevention,
diagnosis, and treatment of disease and
injury affecting the nerves and pulp in
teethand periapical tissues in the gum.
Common endodontic procedures are
root-canal treatment and pulpotomy.
endogenousOf a disease or disorder
that arises within the body rather than
being caused by external factors. (See
also exogenous.)
endometrial ablationA treatment for
persistent menorrhagia(heavy menstru-
al blood loss) that involves endoscopic
examination of the uterus(see endo-
scopy) and removal of the uterus lining,
the endometrium, by diathermyor laser.
endometrial cancerSee uterus, can-
cer of.
endometriosisA condition in which
fragments of the endometriumare locat-
ed in other parts of the body, usually in
the pelvic cavity.
Endometriosis is most common in
women aged 25–40 and may cause
infertility. The cause of endometriosis is
unclear. In some cases, it is thought to
occur because fragments of the endo-
metrium shed during menstruationdo
not leave the body but instead travel up
the fallopian tubes and into the pelvic
cavity, where they adhere to and grow
on any pelvic organ. These displaced
patches of endometrium continue to
respond to hormones produced in the
menstrual cycle and bleed each month.
This blood cannot, however, escape andENDEMIC ENDOMETRIOSISE