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Bradycardia (brad-e-KAHR-dee-uh) is a slow heart rate. The hearts of adults at rest usually beat between 60 and 100 times a minute. If you have bradycardia, your heart beats fewer than 60 times a minute.
Bradycardia can be a serious problem if the heart rate is very slow and the heart can’t pump enough oxygen-rich blood to the body. If this happens, you may feel dizzy, very tired or weak, and short of breath. Sometimes bradycardia doesn’t cause symptoms or complications.
A slow heart rate isn’t always a concern. For example, a resting heart rate between 40 and 60 beats a minute is common in some people, particularly healthy young adults and trained athletes. It also is quite common during sleep.
If bradycardia is severe, a pacemaker may be needed to help the heart beat at an appropriate rate.
Symptoms
A slower than typical heartbeat is called bradycardia. If the slow heartbeat stops the brain and other organs from getting enough oxygen, symptoms may include:
- Chest pain.
- Confusion or memory problems.
- Dizziness or lightheadedness.
- Feeling very tired, especially during physical activity.
- Fainting or near-fainting.
- Shortness of breath.
When to see a doctor
Many things can cause symptoms of bradycardia. It’s important to get a fast, accurate diagnosis and appropriate care. Make an appointment for a health checkup if you are worried about a slow heart rate.
If you faint, have difficulty breathing or have chest pain lasting more than a few minutes, call 911 or emergency medical services.
Bradycardia: Slow Heart Rate | Heart .org
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Bradycardia | Hopkins Medicine
What to Know About Bradycardia | Healthline
In well-trained athletes with normal bradycardia, the slow heartbeat is often a sign of overall good health. In other people with bradycardia, the outlook depends on the underlying disorder. For example, the prognosis is usually good in people with hypothyroidism, since treatment with thyroid hormones can relieve bradycardia and other symptoms related to low hormone levels. In some elderly patients, hormone dosages may need to be increased very slowly over several weeks to prevent straining the heart. The availability of permanent pacemakers has improved the quality of life and prognosis for many people with cardiac arrhythmias.
In well-trained athletes with normal bradycardia, the slow heartbeat is often a sign of overall good health. In other people with bradycardia, the outlook depends on the underlying disorder. For example, the prognosis is usually good in people with hypothyroidism, since treatment with thyroid hormones can relieve bradycardia and other symptoms related to low hormone levels. In some elderly patients, hormone dosages may need to be increased very slowly over several weeks to prevent straining the heart. The availability of permanent pacemakers has improved the quality of life and prognosis for many people with cardiac arrhythmias.