Slow heart rate

A slow heart rate is also called bradycardia. In adults, this often means a resting heart rate below 60 beats per minute. The number alone does not show whether something is wrong.

Your heart rate normally changes with sleep, activity, emotions, illness, and medicines. Healthy, physically active people may have resting rates below 60 because their hearts pump efficiently. A slow rate is more concerning when it is new, much lower than usual, or linked with symptoms.

Sometimes the heart beats slowly because its natural pacemaker is sending signals less often. In other cases, an electrical signal is delayed or blocked as it moves through the heart. This is called a conduction problem.

Many people with a slow heart rate feel completely well. You may first notice it while checking your pulse, using a blood pressure monitor, or wearing a fitness device.

When the heart is not pumping enough blood for your needs, you may notice:

• Dizziness or feeling light-headed
• Unusual tiredness or weakness
• Shortness of breath
• Reduced ability to exercise
• Trouble concentrating or feeling confused
• Near-fainting or fainting
• Chest discomfort
• A pulse that feels slow, irregular, or as though beats are missing

Watches and phone apps can sometimes give incorrect readings, especially during movement or when skin contact is poor. Recheck an unexpected result while sitting quietly.

A slow heart rate is often a normal response to rest or physical conditioning. It commonly occurs during sleep and in people who regularly do endurance exercise.

Medicines are another common cause. These include some beta blockers like metoprolol or propranolol, calcium channel blockers like amlodipine or diltiazem, heart rhythm medicines, and digoxin. Some medicines used for other conditions can also slow the pulse. Do not stop a prescribed medicine on your own.

Less common causes include:

• An underactive thyroid
• Changes in blood salts, such as potassium
• Sleep apnea, which interrupts breathing during sleep
• Age-related changes in the heart’s electrical system
• Inflammation or infection affecting the heart
• Previous heart surgery or damage to heart tissue

A heart attack or serious disruption of the heart’s electrical signals can also cause a slow rate. These causes usually need urgent assessment, especially when symptoms begin suddenly.

Call emergency services if a slow heart rate occurs with:

• Fainting, collapse, or difficulty waking
• Severe trouble breathing
• New or severe chest pain
• Sudden confusion
• Pale, blue, grey, or very sweaty skin
• No normal breathing or no detectable pulse

If someone is unresponsive and not breathing normally, begin CPR if you can and use an automated external defibrillator if one is available.

Seek same-day medical advice if a slow pulse is new and comes with dizziness, unusual weakness, shortness of breath, near-fainting, or reduced ability to do normal activities. An awake heart rate that repeatedly stays below 40 and is not normal for you also needs prompt assessment.

Book a routine appointment if readings are repeatedly slower than usual but you otherwise feel well. Arrange follow-up if symptoms are mild but keep returning, or if a medicine may be affecting your heart rate.

A clinician will ask when the slow rate started, whether it comes and goes, and what symptoms occur with it. They will also review your medicines, supplements, medical history, exercise habits, and sleep symptoms.

An electrocardiogram, or ECG, records the heart’s electrical activity. It can show the heart rate and whether electrical signals are delayed or blocked. Because a brief ECG may miss an occasional problem, you may be asked to wear a portable heart monitor for a day or longer.

Blood tests may check thyroid function, blood salts, and other possible causes. Depending on your symptoms, testing may also include an exercise test, a heart ultrasound, or an assessment for sleep apnea.

Bring a record of your pulse readings and symptoms. Include the time, what you were doing, and any medicines taken around that time.

A slow heart rate that is normal for you and causes no symptoms may not need treatment. Management depends on the cause and on whether the heart is supplying enough blood to the body.

Treatment may involve adjusting a medicine under medical supervision or treating a thyroid problem, sleep apnea, infection, or blood-salt imbalance. A pacemaker may be considered when a lasting electrical problem causes important symptoms. This small implanted device helps prevent the heart from beating too slowly.

To check your pulse, sit quietly for several minutes. Feel at your wrist or the side of your neck and count the beats for a full minute, especially if the rhythm seems uneven. Record the result rather than repeatedly checking it.

Avoid strenuous activity if it brings on dizziness, chest discomfort, or unusual breathlessness. Do not drive if you have fainted or feel likely to faint. Do not try to raise your heart rate with extra caffeine or unprescribed medicines.

A slow heart rate may be temporary, such as during sleep or while taking a particular medicine. It may also continue long term because of physical fitness or changes in the heart’s electrical system.

The outlook depends more on the cause and symptoms than on one pulse reading. People without symptoms may only need observation. If treatment is needed, addressing the cause often improves the heart rate or prevents troublesome episodes.

Keep follow-up appointments if monitoring has been arranged. Seek earlier review if symptoms become more frequent, happen with less activity, or change in severity.

Is a heart rate below 60 always dangerous?

No. It can be normal during sleep, at rest, or in physically active people. Symptoms, your usual rate, and the heart’s electrical pattern provide more useful context.

Can anxiety cause a slow heart rate?

Anxiety more often speeds up the heart, but heart rate can change with breathing, fainting reactions, or medicines used for anxiety. A repeated slow rate should not automatically be blamed on stress.

Can medicines cause bradycardia?

Yes. Several heart and blood pressure medicines can slow the pulse. Other medicines may contribute as well. Ask for a medication review rather than skipping or stopping doses.

What is the difference between bradycardia and heart block?

Bradycardia describes a slow rate. Heart block means an electrical signal is delayed or stopped as it travels through the heart. Heart block can cause bradycardia, but not every slow heart rate is due to heart block.

Is a wearable device enough to check my heart?

A wearable can identify a trend, but it cannot fully assess the heart’s electrical system. An ECG is usually needed to confirm the rhythm.