5.3 Heart disease
Learning outcomes
Students should understand the following:
 Atheroma as the presence of fatty material within the
walls of arteries.
 The link between atheroma and the increased risk of
aneurysm and thrombosis.
 Myocardial infarction and its cause in terms of an
interruption to the blood flow to heart muscle.
Diseases of the heart and circulation are called
cardiovascular disease:
 Atheroscelrosis – build up of fatty deposits on the inner
linings of arteries (atheroma) .
 Coronary heart disease (CHD)- an atheroma in coronary
arteries.
 Aneurysm – a weakened and ballooning area of an
artery.
 Cerebrovascular accident – blockage of a blood vessel in
the brain (stroke).
Condition
Atherosclerosis
(atheroma)
Coronary heart
disease (CHD)
Aneurysm
Cerebrovascular
accident
(Stroke)
Description
Diagram
Atherosclerosis
Build up of fatty deposits on the inner
linings of arteries (atheroma).
Fat is transported in the body as
lipoproteins:
 Low density lipoproteins (LDL)
from saturated fats more likely to
cause atheroma.
 High density lipoproteins (HDL)
from polyunsaturated fats are less
likely to be deposited.
Atheroma
 Most commonly form in larger arteries and are made
up of deposits of cholesterol, fibres and dead muscle
cells.
 They bulge into the lumen and cause a narrowing and
therefore restriction of blood flow.
Atheroma increase the chance of a blood clot forming.
 Thrombus – stationary
blood clot
 Embolism – mobile blood
clot
Coronary heart
disease (CHD)
An atheroma in coronary arteries.
Narrowing of the coronary arteries
may restrict blood flow and starve
an area of cardiac muscle of oxygen – angina
Blood clots may form in these narrowed blood vessels
causing a blockage and depriving cardiac muscle of it’s
blood supply. These areas of heart muscle do not
function properly and my die. If the cardiac muscle
does not contract this can lead to a myocardial
infarction (heart attack).
Coronary Heart disease 1.swf
Aneurysm
A weakened and ballooning area of an
artery, due to damage or loss of
elastic tissue.
A burst aneurysm may cause serious internal bleeding.
Aneurysm occur most frequently in the cerebral arteries
and brain.
Aneurysms can only be treated by surgery.
Cerebrovascular
accident (stroke)
Blockage of a blood vessel in the
brain or a burst aneurysm in a
cerebral artery. The effects are:
 confined to one side of the brain;
 range from slight to severe paralysis;
 speech is often effected;
 damage may be permanent or may
make gradual recovery
Strokes are more common in older people.
Stroke.swf
Learning outcomes
Students should understand the following:
 Atheroma as the presence of fatty material within the
walls of arteries.
 The link between atheroma and the increased risk of
aneurysm and thrombosis.
 Myocardial infarction and its cause in terms of an
interruption to the blood flow to heart muscle.