heart normally beats in a regular rhythm and rate that is just right for the
work your body is doing at any moment. The usual resting heart rate for adults
is between 50 to 100 beats per minute. Children have naturally higher normal
heart rates than adults.
heart is a pump made up of
four chambers : two upper chambers (atria) and two lower chambers
(ventricles). It is powered by an
electrical system that puts out pulses in a regular
rhythm. These pulses keep the heart pumping and keep blood flowing to the lungs
When the heart beats too fast, too slow, or with a
skipping (irregular) rhythm, a person is said to have an
arrhythmia. A change in the heart's rhythm may feel
like an extra-strong heartbeat (palpitation) or a fluttering in your
chest. Premature ventricular contractions (PVCs) often cause this feeling.
A heartbeat that is occasionally irregular usually is not a concern if
it does not cause other symptoms, such as dizziness,
lightheadedness, or shortness of breath. It is not
uncommon for children to have extra heartbeats. In healthy children, an extra
heartbeat is not a cause for concern.
changes in heart rate or rhythm are minor and do not require medical treatment
if you do not have other symptoms or a history of heart disease. Smoking,
drinking alcohol or caffeine, or taking other stimulants such as diet pills or
cough and cold medicines may cause your heart to beat faster or skip a beat.
Your heart rate or rhythm can change when you are under stress or having pain.
Your heart may beat faster when you have an illness or a fever. Hard physical
exercise usually increases your heart rate, which can sometimes cause changes
in your heart rhythm.
Dietary supplements, such as goldenseal,
oleander, motherwort, or ephedra (also called ma huang), may cause irregular
It is not uncommon for pregnant women to have minor
heart rate or rhythm changes. These changes usually are not a cause for concern
for women who do not have a history of heart disease.
athletes usually have slow heart rates with occasional pauses in the normal
rhythm. Evaluation is usually not needed unless other symptoms are present,
such as lightheadedness or fainting (syncope), or
there is a family history of heart problems.
Irregular heartbeats change the amount of blood that flows to the lungs
and other parts of the body. The amount of blood that the heart pumps may be
decreased when the heart pumps too slow or too fast.
atrial fibrillation that start in the upper chambers
of the heart can be serious, because they increase your risk of forming blood
clots in your heart. This in turn can increase your risk for having a stroke or
a blood clot in your lungs (pulmonary embolism). People who have
heart failure, or a history of heart attack should be
more concerned with any changes in their usual heart rhythm or rate.