Angina is not a disease. It is a pain, a
symptom of another disease, the very common
condition called atherosclerosis, which
affects many arteries. In this case, the
arteries concerned are the coronary arteries
of the heart. These two arteries and their
branches supply the very active muscle of
the heart with the blood it needs to keep
beating. If they can provide enough blood
so that the heart muscle gets the amount
of glucose fuel and oxygen it need for its
energy supply, the heart goes on beating
painlessly.
But if the coronary
arteries have been narrowed and can’t
get the blood to the heart muscle fast enough,
abnormal levels of substances collect in
the muscles to the point of causing pain.
This pain is angina.
The full name for
the symptom is angina pectoris. This is
Latin for ‘pain in the chest’.
The symptom is far more common in men than
in pre-menopausal women. After the menopause,
women who are not on HRT are as likely to
get angina as men are as they no longer
have the same hormone protection.
Causes
Angina occurs when
arteriosclerosis has caused so much narrowing
of the coronary arteries that they are not
able to supply enough blood to the heart
muscle during exercise. In most cases angina
doesn’t occur while you’re at
rest. But the stronger or more prolonged
the exertion, the greater is the amount
of blood that the heart needs.
Healthy coronary arteries
can pass enough blood to allow the heart
to reach its maximum output without pain.
But narrowing of the coronary arteries will
always mean that there is a limit to the
rate at which blood can get to the heart
muscle, in spite of its needs.
Angina symptoms develop
when the heart demands more oxygen than
can be supplied or when the supply drops
below demand.
Treatment
The drug glyceryl
trinitrate (nitroglycerine) is highly effective
in controlling the pain of angina. You can
take it as a tablet that dissolves under
your tongue, and the pain is usually relieved
in two to three minutes. The drug is also
available in skin patches (transdermal patches)
and as a spray (again for under the tongue),
and all forms are available from a pharmacy
without prescription. Nitrates have a powerful
action in widening (dilating) arteries,
including the coronary arteries, thus improving
the blood supply to the heart muscle.
| 
Angina
