Bradycardia is a slow or irregular heart rhythm, usually fewer than 60 beats per minute. At this rate, the heart is not able to pump enough oxygen-rich blood to the body during normal activity or exercise. As a result, you may feel dizzy or have chronic lack of energy, shortness of breath, or even fainting spells. What's too slow for you may depend on your age and physical condition. Physically active adults (and athletes) often have a resting heart rate slower than 60 BPM but it doesn't cause problems and is normal for them. Your heart rate may fall below 60 BPM during deep sleep. Also, elderly people are more prone to problems with a slow heart rate.
Symptoms
A heart rhythm that's too slow can cause insufficient blood flow to the brain with symptoms such as:
- Fatigue or feeling tired or weak
- Dizziness or lightheadedness
- Fainting or near-fainting spells
- Some people may feel short of breathe
Causes
Bradycardia can be caused by:
- Changes in the heart that are the result of aging.
- Diseases that damage the heart's electrical system. These include coronary artery disease, heart attack, and infections such as endocarditis and myocarditis.
- Conditions that can slow electrical impulses through the heart. Examples include having a low thyroid level (hypothyroidism) or an electrolyte imbalance, such as too much potassium in the blood.
Treatment
The treatment strategy for bradycardia depends on what is causing the slower than normal heart rate as well as the patient’s symptoms. If another medical problem, such as hypothyroidism, is causing a slow heart rate, treating it may indirectly affect bradycardia. Treating these problems with new medicines, or adjusting the doses of the medicines you are currently taking, may restore a normal heartbeat.
If the damage within the heart’s electrical system is causing a slow heart rate, you may be eligible for an implantable heart device called a pacemaker. Pacemakers are small devices that are implanted under the skin, most often below your collarbone on the left or right side of your chest, to help restore the heart’s rhythm. By sending tiny electrical signals to the heart to increase the heart rate, a pacemaker can relieve the symptoms of bradycardia.
Risk factors
Age
A key risk factor for bradycardia is age. Heart problems, which are often associated with bradycardia, are more common in older adults.
Risk factors related to heart disease
Bradycardia is often associated with damage to heart tissue from some type of heart disease. Therefore, factors that increase your risk of heart disease can also increase the risk of bradycardia. Lifestyle changes or medical treatment might decrease the risk of heart disease associated with the following factors:
- High blood pressure
- Smoking
- Heavy alcohol use
- Psychological stress or anxiety
Bradycardia is often the result of another heart condition, so taking steps to live a heart-healthy lifestyle will usually improve your overall health. The most effective way to prevent bradycardia is to reduce the risk of developing heart disease. If you already have heart disease, monitor it and follow your treatment plan to lower the risk of bradycardia.
