It's a clinical diagnosis and it's a
syndrome i.e. a collection of symptoms and
signs, but the standard textbook
definition is that it's a situation
where the heart cannot meet the demands
of the circulation.
It's not the same as
a heart attack, you can have a heart
attack without having heart failure, it's
not the same as a cardiac arrest, which
is a rhythm disorder, but it's a specific
condition which doctors recognise where
congestion occurs in the lungs and in
the tissues because the heart cannot
pump properly.
So the most common cause is
where the heart muscle actually fails to
contract properly, there are several
clinical and medical reasons why that
can happen.
When the heart fails to contract
it's just pumping weakly, but nowadays
we see a different sort of heart
failure where the heart can contract
properly but doesn't actually relax
and this relaxation abnormality is often
called diastolic heart failure, which is
really only recently being increasingly recognised.
Well, the symptoms of heart failure
relate to the fact that looking
at it simplistically there's back
pressure because the pump isn't working.
If we take the lungs, if the lungs which are
normally like two dry sponges.
If they become congested with fluid
they become like wet sponges, which are more
difficult to move, so the first symptom
is breathlessness, and this can be
breathlessness initially on climbing
stairs or walking up an incline but it
gets worse it can become breathlessness
on walking on the flat on doing things
like bed making or housework or pushing
a shopping trolley, and then when the
lungs become really congested the
patient will notice as they lie flat in
bed at night their lungs fill up with
fluid and they can't lie flat, they have
to sleep sitting up.
That's the left side
of the heart when the right side of the
heart fails it's the peripheral tissues
that get congested, the commonest thing
that happens is that the ankles swell it
abdomen may swell because the liver
enlarges they may be fluid at the base
of the spine and the patient may get
very very fatigued and lethargic.
Well, any condition that damages the heart muscle
can lead to heart failure and
this can be due to blocked arteries, the
coronary arteries which supply the heart
with blood, if the heart becomes short of
blood and has lots of heart attacks the
heart will stop beating.
Then there are diseases of the valves that open and
shut and if they're left too long
without treatment, that can put a strain
on the heart that can damage it and
there are conditions that can primarily
affect the heart muscle which we call
cardiomyopathies which is specifically
abnormalities of heart muscle for example
such as drinking too much alcohol,
such as certain drugs, such as even viruses
that can damage the heart muscle.
It may well be underlying causes as well such
as anaemia, where the heart is asked to do
more work, or even a change in the heart rhythm
There's a very common arrhythmia called
atrial fibrillation, where the upper
chambers of the heart go out of rhythm
and a patient may have no symptoms until
they develop this arrhythmia and then
the heart can fail.
Now there are other
less common causes such as some
infiltrative diseases which can particularly
affect the relaxation, and one of the most
common of those is long-standing,
untreated high blood pressure which can
commonly cause heart failure if it's not
treated properly.
So, obviously prevention
is better than cure, but if someone has
heart failure there are several
treatments available.
First of all let's
correct the underlying cause so treat
the anaemia, treat the rhythm disorder,
reduce salt intake, treat the high blood pressure.
But then there are drugs known
as diuretics, which are commonly known as
water tablets, which can be given by
mouth or intravenously, which make the
kidneys get rid of the excess fluid and
clear the congestion.
There are other
drugs we use to take the strain off the
heart several groups of drugs:
Ace inhibitors, beta blockers, and nitrates
all of which have beneficial effects and
ease the load on the strained heart.
Apart from drugs there are things like
there are some devices that we can use
to improve the function of a heart for
example there are special sorts of
pacemaker called resynchronisation
pacemakers, which force the chambers of
the heart to beat more synchronously and
improve function and can actually
improve life expectancy, and they can
often be combined with a device called a
defibrillator which will administer a
life-saving electric shock if a patient
with heart failure, becomes, goes into
unstable, life-threatening rhythm.
In certain circumstances surgery
can be indicated to correct an abnormal valve,
or to bypass the coronary artery.