What is Bradycardia?

Medically Reviewed by James Beckerman, MD, FACC on August 17, 2022
4 min read

Generally, it is normal to have a slower heart rate when you’re resting. It can be a sign of good health. But if it’s too slow, it could be a symptom of a condition called bradycardia.

Normally, your heart beats 60 to 100 times a minute when you’re at rest. But with bradycardia, it goes down to less than 60 beats a minute.

This might not cause a problem for some people. But it could be a clue that you have an issue with the electrical system in your heart. You need to see a doctor who can figure out why it’s beating slowly and if you should get treatment.

Electrical signals travel through the heart’s four chambers -- two on the top called the atria and below them, the two ventricles. These signals prompt it to beat in a steady rhythm. But pulses don’t always fire off as they should.

This creates what’s called arrhythmias, or abnormal heartbeats.

Some conditions cause the heart to beat too fast or to flutter. With bradycardia, it’s the opposite. The electrical problem slows down the time in between heartbeats.

You may simply have a slower-than-normal heart rate that doesn’t cause any symptoms. The electrical activity may be working fine, just a little slower than it does in most people. You wouldn’t even be diagnosed with this condition.

And even with bradycardia, you may never notice any symptoms or need treatment. But that’s not always the case.

The biggest concern is your heart isn’t doing well enough at pumping blood to all the organs and tissues that need it. When this happens, the following may develop:

  • Lightheadedness or dizziness
  • Confusion or a hard time concentrating
  • Fainting
  • Shortness of breath (with or without chest pain)

You may also find that you tire out easily with even just a little activity.

If you check your heart rate and it’s regularly below 60 beats per minute, be aware of those symptoms.

If you have no other symptoms, you probably don’t need to see a doctor right away. You may exercise a lot, and a slow heart rate could be a sign of how fit you are. But, bring it up at your next appointment.

If you or a loved one notices mild to medium symptoms, go to a doctor quickly.

If you or a loved one faints, has chest pains or trouble breathing, call 911.

Tiredness, trouble concentrating, or breathing harder may just seem like part of growing older. But sometimes it’s more than that.

Be sure to tell your doctor about all your symptoms. If you wear out more easily now than you did a month or year ago, let them know.

The chances of getting bradycardia increase as you get older, though that’s true of most heart conditions. The causes of bradycardia can vary greatly from one person to the next.

The abnormal rhythm can show up after a heart attack or as a side effect of heart surgery. Other things that can lead to it:

  • Certain medications, such as those to treat high blood pressure and other arrhythmias, or abnormal heartbeats
  • A congenital defect, or problem you’re born with
  • Thyroid disease, an imbalance of hormones in the body
  • Obstructive sleep apnea, when your breathing pauses many times throughout the night

Bradycardia can be a little hard for doctors to figure out, because it’s not always present all the time. Your heart can go in and out of slow rhythms.

Your doctor will be able to make the diagnosis if you’re having a bout of bradycardia during a test called an electrocardiogram. Often called an EKG, it’s a way to measure your heart’s electrical system.

If your heart rate appears normal, but you have had symptoms of bradycardia, your doctor may have you wear a 24-hour monitor.

Your doctor will ask about your personal and family health histories, as well as any symptoms you’ve had.

If your doctor decides that you have bradycardia, the treatment plan will be based on the likely cause of the problem.

For instance, if the cause is hypothyroidism, or low thyroid function, treating that may take care of the heart rate issue.

If there is no clear physical cause, your doctor may change medications that might be slowing your heart. Beta blockers are sometimes prescribed to relax your heart muscle. But if they cause you to have a really slow heart rate, your doctor might lower the dosage or give you a different drug.

If these approaches don’t work and your condition is serious enough to put your brain and other organs at risk, you may need a pacemaker.

A surgeon will put this small device into your chest. It has thin, flexible wires, called leads, which extend to the heart. They carry small electrical charges that help keep the heart pumping at a steady rate.

If you have been given a pacemaker, listen to your doctor’s instructions about how it operates and any signs it might not be working.