What Is a
“Slow” Heart Rate?
Your heart rate is the number of
beats (rhythmic contractions) per minute of your heart. Your heart is the
muscular organ, located in the chest, behind and to the left of the breastbone
that maintains circulation of the blood. Heart rate is a measure of cardiac
Heart rate is one of the vital
signs. Vital signs like body temperature, pulse, breathing rate, and blood
pressure provide information about a person’s state of health. Any abnormality
of these signs can offer diagnostic clues.
A slow heart rate is considered
anything slower than 50 beats per minute for an adult or child at rest.
Alternative names for this
- heart rate decreased
- heartbeats decreased
- low heart rate
- decreased heart rate
- pulse slow
- pulse rate decreased
- slow heartbeat
- slow pulse
Understanding Your Heart Rate by the Numbers
You can measure your heart rate.
First, find your heart rate by holding a finger to the radial artery at the
wrist. Other places it can be measured are at the neck (carotid artery), the
groin (femoral artery), and the feet (dorsalis pedis and posterior tibial
arteries). Then, count the number of beats per minute while you are resting.
Here are some numbers to keep in
- The resting adult heart rate is
normally 60 to 100 beats per minute.
- Athletes or people on certain
medications may have a lower resting normal rate.
- The normal heart rate for
children aged 1 to 8 years is 80 to 100 beats per minute.
- The normal heart rate for infants
age 1 to 12 months is 100 to 120 beats per minute.
- The normal heart rate for
newborns (under 1 month old) is 120 to 160 beats per minute.
Problems That Can Accompany a Slow Heart Rate
Your heart rate should be strong
and regular without any missed beats. If it’s beating slower than the normal
rate, it might indicate a medical problem. Fainting, dizziness, loss of
consciousness, weakness, and fatigue can accompany a slow heart rate.
In some cases, a slow heart rate
is an indication of an extremely healthy heart. Athletes, for instance, often
have lower than normal resting heart rates because their heart is strong and
doesn’t have to work as hard to pump blood throughout the body. However, when a
slower heart rate is uncommon and/or accompanied by other symptoms, it could be
a sign of something more serious.
Potential Underlying Causes of a Slow Heart Rate
A thorough medical evaluation is
necessary to determine the cause of a slow heart rate. An electrocardiogram
(EKG or ECG), laboratory tests, and other diagnostic studies may be done.
Potential medical causes of a slow heart rate
- abnormal heart rhythms
- anorexia nervosa
- autonomic dysreflexia
- autonomic neuropathy
- congestive cardiomyopathy
- heart attack
- elevated potassium
- intracerebral hemorrhage
- marine animal stings or bites
- side effects of medications
- subarachnoid hemorrhage
- sick sinus syndrome
- AV node damage
Treating the Cause of a Slow Heart Rate
Treatment depends on the
underlying condition. If slow heart rate is due to the effect of medication or
toxic exposure, this must be treated medically. An external device (pacemaker)
implanted into the chest to stimulate heartbeats is the preferred treatment for
certain types of bradycardia.
Because a low heart rate could
indicate medical problems, make an appointment with your doctor if you notice
any changes in your heart rate, especially if the changes are accompanied by
Recognizing a Potential Emergency Situation
In certain situations, a slow
heart rate could indicate a medical emergency. The following symptoms can be
- loss of consciousness
- chest pain
- passing out or fainting
- shortness of breath
- arm pain
- jaw pain
- severe headache
- blindness or visual change
- abdominal pain
- pallor (pale skin)
- cyanosis (bluish skin color)
If you have any of these symptoms
and a change in your heart rate, call 911.