Bma Illustrated Medical Dictionary

include fainting, lack of energy, chest

pain on exertion due to angina, and

breathing difficulty.

Chest X-ray, ECG, and echocardiogra-

phymay be carried out to diagnose

aortic stenosis. A cardiac catheter can

be used to demonstrate the degree of

stenosis (see catheterization,cardiac).

Heart-valve surgerymay be needed to

widen or replace the damaged valve.

aortitisInflammation of the aorta(the

main artery of the body). Aortitis is a

rare condition that occurs in people

with arteritisor untreated syphilisand in

some people with ankylosing spondylitis.

Aortitis may cause part of the aorta to

widen and its walls to become thinner.

This may lead to an aneurysm(balloon-

ing of the artery). Aortitis may damage

the ring around the aortic valve in the

heart, leading to aortic incompetence.

aortographyAn imaging technique that

enables the aorta(the main artery of the

body) and its branches to be seen clear-

ly on X-ray film following injection of a

contrast medium(a substance that is

opaque to X-rays). Aortography is used

if surgery is needed to treat an aneu-

rysm(ballooning of the aorta).

aperientA mild laxative drug.

apex The uppermost surface of a struc-

ture, for example the top, end, or tip of

an organ such as a lung or the heart.

apex beat A normal hearbeat felt

through the chest wall. As the heart con-

tracts, its tip hits the chest wall and can

be felt between the 5th and 6th ribs on

the left side of the chest. The apex beat

is displaced when the heart is enlarged.

Apgar scoreA system designed to

assess the condition of a newborn baby.

Five features are scored 1 minute and

again 5 minutes after birth. These are

breathing, heart-rate, colour, muscle

tone, and response to stimulation.

aphakiaThe absence of the lensfrom

the eye. Aphakia may be congenital,

may result from surgery (for example,

cataract surgery), or may be due to a

penetrating injury. Aphakia causes sev-

ere loss of focusing in the affected eye

and requires correction by implanting a

lens or with contact lenses or glasses.

aphasiaA complete absence of previ-

ously acquired language skills, caused

by a brain disorder that affects the abil-

ity to speak and write, and/or the ability

to comprehend and read. Related dis-

abilities that may occur in aphasia are

alexia (word blindness) and agraphia

(writing difficulty).

Language function in the brain lies in

the dominant cerebral hemisphere (see

cerebrum). Two particular areas in this

hemisphere, Broca’s and Wernicke’s

areas, and the pathways connecting the

two, are important in language skills.

Damage to these areas, which most

commonly occurs as a result of stroke

or head injury, can lead to aphasia.

Some recovery from aphasia is usual

following a stroke or head injury,

although the more severe the aphasia,

the less the chances of recovery. Speech

therapyis the main treatment. (See also

dysphasia; speech; speech disorders.)

apheresisA procedure in which blood

is withdrawn from a donor and is re-

infused after one or more selected

components have been separated and

removed. In plasmapheresis, antibodies

that are causing a disease are removed;

and in leukapher-

esis, white blood

cells are removed.

aphoniaComplete

loss of the voice,

which may result

from surgery to the

larynx, or it may

be sudden in onset

and due to emo-

tional stress. (See

also dysphonia.)

aphrodisiacAny

substance that is

AORTITIS APHRODISIAC

A

SIGN

Heart-rate

Breathing

Muscle tone

Response to

stimulation

Colour

SCORE 0

None

None

Limp

None

Pale; blue

SCORE 1

Below 100 beats

per minute

Weak cry; irregular

breathing

Some muscle

tone

Grimace or

whimpering

Blue extremities

SCORE 2

Over 100 beats

per minute

Strong cry; regular

breathing

Active

movement

Cry, sneeze

or cough

Pink

APGAR SCORE