A slow heart rate can indicate that something disrupted the electrical impulses that control the heart's rhythm, according to Mayo Clinic. A heart rate under 60 beats per minute, called bradycardia, is also normal in some healthy, physically active adults and can be normal during very deep sleep, notes the American Heart Association.Continue Reading
Some common problems that impact the electrical impulses in the heart include high blood pressure, heart tissue damage caused by a heart attack or disease, an infection of the actual heart, a congenital heart defect, and heart damage caused by aging, states Mayo Clinic. Sometimes, heart surgery can cause bradycardia. Other times, medication used to treat high blood pressure or heart rhythm can cause a low heart rate.
There are other causes of bradycardia that people might not immediately associate with the heart, explains Mayo Clinic. Hypothyroidism, excessive iron in the organs, and electrolyte imbalances can also affect the heart rhythm. Sleep apnea and diseases that cause inflammation, such as lupus or rheumatic fever, may also cause low heart rates. Some types of medications, such as those that treat psychosis, can also impact heart rates.
When conditions or medications impact the sinus node, which is located in the right atrium of the heart, some people may experience periods of slow heart rates as well as times when their hearts race, notes Mayo Clinic. The sinus node may also have its electrical signals blocked or may not produce electrical impulses at the correct rhythm. If the problem is not in the sinus node, the patient may have an atrioventricular block that prevents electrical signals from reaching the heart's ventricles.Learn more about Cardiac Health