Diagnosis

To diagnose bradycardia, a health care provider will usually perform a physical exam and listen to your heart with a stethoscope. He or she may ask you questions about your symptoms and medical history.

Your health care provider may recommend tests to check your heart rate and see if you have a heart problem that can cause bradycardia. Blood tests may be done to check for other conditions that can cause slow heartbeats, such as an infection, an underactive thyroid (hypothyroidism) or an electrolyte imbalance.

Tests

An electrocardiogram (ECG or EKG) is the main test used to diagnose bradycardia. An ECG measures the electrical activity of the heart. Sticky patches (electrodes) are placed on the chest and sometimes the arms and legs. Wires connect the electrodes to a computer, which displays the results. An ECG can show if the heart is beating too slow, too fast or not at all.

Because an ECG can't detect bradycardia unless the slow heartbeat occurs during the test, your health care provider might recommend a portable ECG device. Portable ECG devices include:

  • Holter monitor. Carried in a pocket or worn on a belt or shoulder strap, this device records the heart's activity continuously for 24 hours or longer.
  • Event recorder. This device is similar to a Holter monitor, but it records only at certain times for a few minutes at a time. It's worn longer than a Holter monitor, typically 30 days. You generally push a button when you feel symptoms. Some devices automatically record when an irregular heart rhythm is detected.

An ECG may be done with other tests to understand how bradycardia affects you. These tests include:

  • Tilt table test. This test may help your health care provider better understand how your bradycardia causes fainting spells. As you lie flat on a special table, the table is tilted as if you were standing up. A tilt test is done to see if a change in position causes fainting.
  • Stress exercise test. An ECG may be done to monitor your heart's activity while you ride on a stationary bicycle or walk on a treadmill. If you have difficulty exercising, a drug may be given to stimulate the heart in a way that's similar to exercise.

A sleep study may be recommended if your health care provider thinks that repeated pauses in breathing during sleep (obstructive sleep apnea) are causing bradycardia.

Treatment

Treatment for bradycardia depends on the severity of symptoms and the cause of the slow heart rate. If you don't have symptoms, treatment might not be necessary.

Bradycardia treatment may include lifestyle changes, medication changes or an implanted device called a pacemaker. If an underlying health problem, such as thyroid disease or sleep apnea, is causing the slow heart rate, treatment of that condition might correct bradycardia.

Medications

Many medications, including those used to treat other heart conditions, can cause bradycardia. Always let your health care provider know about all the medications you take, including those bought without a prescription.

If a medication you're taking is causing bradycardia, your health care provider may recommend a lower dosage or a different medication.

Surgery or other procedures

When other treatments aren't possible and bradycardia symptoms are severe, a device called a pacemaker is necessary to control the heart rhythm. Pacemakers work only when needed. When the heart beats too slowly, the pacemaker sends electrical signals to the heart to speed up the beat.

Having a pacemaker implanted requires a surgical procedure. One or more wires are inserted into a major vein under or near the collarbone and guided to the heart using X-rays as a guide. One end of each wire is secured at the appropriate area in the heart, while the other end is attached to a device (pulse generator) implanted under the skin beneath the collarbone.

A leadless pacemaker is smaller and typically requires a less invasive surgery to implant the device.

Preparing for your appointment

Whether you start by seeing your primary care provider or get emergency care, you'll likely be referred to a doctor trained in heart conditions (cardiologist) for diagnosis and treatment.

What you can do

If possible, write down the following information and take it with you to your health care provider's appointment:

  • Your symptoms, including those that seem unrelated to your heart, and when they began
  • Important personal information, including major stresses or recent life changes and your medical history
  • Medications, including vitamins and other supplements you take, including doses
  • Questions to ask your health care provider

If possible, take along a family member or friend to help you remember the information you receive.

For bradycardia, basic questions to ask your health care provider include:

  • What is likely causing my slow heart rate?
  • What tests do I need?
  • What's the most appropriate treatment?
  • What are the possible complications?
  • How will my heart be monitored?
  • How often will I need follow-up appointments?
  • How will other conditions I have or medications I take affect my heart problem?
  • Do I need to restrict my activities?
  • Are there brochures or other printed material I can have? What websites do you recommend?

Don't hesitate to ask other questions.

What to expect from your doctor

Your health care provider is likely to ask you questions, such as:

  • Have you had fainting spells?
  • Does anything, such as exercise, worsen your symptoms?
  • Do you smoke?
  • Are you being treated for heart disease, high blood pressure, high cholesterol or other conditions that can affect your heart?