The
term "heart failure" makes it sound like the heart is no longer
working at all and there's nothing that can be done. Actually, heart failure
means that the heart isn't pumping as well as it should be.
Your
body depends on the heart's pumping action to deliver oxygen- and nutrient-rich
blood to the body's cells. When the cells are nourished properly, the body can
function normally.
With
heart failure, the weakened heart can't supply the cells with enough blood (View an animation of heart failure) . This results in fatigue and shortness of
breath. Everyday activities such as walking, climbing stairs or carrying
groceries can become very difficult.
Heart
failure is a serious condition, and usually there's no cure. But many people
with heart failure lead a full, enjoyable life when the condition is managed
with heart failure
medications and healthy lifestyle changes. It's also helpful to have the support of
family and friends who understand your condition.
How the normal heart works
The
normal healthy heart is a strong, muscular pump a little larger than
a fist. It pumps blood continuously through the circulatory system.
The
heart has four chambers, two on the right and two on the left:
- Two upper chambers called atria
(one is an atrium)
- Two lower chambers called
ventricles
Oxygen-rich
blood travels from the lungs to the left atrium, then on to the left ventricle,
which pumps it to the rest of the body.
The
right atria takes in oxygen-depleted blood from the rest of the body and sends
it back out to the lungs through the right ventricle.
The
heart pumps blood to the lungs and to all the body's tissues by a sequence of
highly organized contractions of the four chambers. For the heart to function
properly, the four chambers must beat in an organized way.
What is heart failure?
Heart
failure is a chronic, progressive condition in which the heart muscle is unable
to pump enough blood through to meet the body's needs for blood and
oxygen. Basically, the heart can't keep up with its workload.
At
first the heart tries to make up for this by:
- Enlarging. When the heart
chamber enlarges, it stretches more and can contract more strongly, so it
pumps more blood.
- Developing more muscle mass.
The increase in muscle mass occurs because the contracting cells of the
heart get bigger. This lets the heart pump more strongly, at least
initially.
- Pumping faster. This helps to
increase the heart's output.
The
body also tries to compensate in other ways:
- The blood vessels narrow to
keep blood pressure up, trying to make up for the heart's loss of power.
- The body diverts blood away
from less important tissues and organs to maintain flow to the most vital
organs, the heart and brain.
These
temporary measures mask the problem of heart failure, but they don't solve it.
Heart failure continues and worsens until these substitute processes no longer
work.
Eventually
the heart and body just can't keep up, and the person experiences the fatigue,
breathing problems or other symptoms that usually prompt a trip to the doctor.
The
body's compensation mechanisms help explain why some people may not become
aware of their condition until years after their heart begins its decline.
(It's also a good reason to have a regular checkup with your doctor.)
Heart
failure can involve the heart's left side, right side or both sides. However,
it usually affects the left side first.
Learn
about:
"This
content was last reviewed on 08/20/2012."