Bradycardia refers to slow heart rate. A person with bradycardia has a heart rate that is much slower than the normal heart rate. Normal people have a heart rate that ranges between 60 and 100 beat per minute (at rest). For people with bradycardia, the heart rate is generally lower than 60 beats per minute. For normal people during sleep though the heartbeat drops to 40 to 50 beat per minute, this is considered normal. In the case of healthy athletes, the heartbeat might even drop to 30 to 40 beat per minute and this is also considered normal. However, if one has a relatively slow heartbeat as per one’s medical condition, it is called relative bradycardia (heartbeat less than 60 beats per minute). Bradycardia is an arrhythmia (See: Arrhythmia), an irregular heart rhythm, that shows up symptoms only if the number of beats per minute drops less than 50. The heartbeats are powered by electrical impulses and an underlying medical condition affecting the heart’s electrical impulses causes bradycardia. Bradycardia might also be caused due to the natural aging process, congenital diseases, scar tissue of the heart due to previous heart attacks, coronary heart disease, myocarditis (an infection of the heart), sinus node dysfunction, and ischemic heart disease. Bradycardia might also be caused due to non-cardiac causes including the use of recreational drugs, hypothyroidism, electrolyte imbalance, neurological disorders, endocrine disorders, and reactions to medications. Complications of bradycardia include chest pain, syncope (See: Syncope), and heart failure. Symptoms of bradycardia include shortness of breath, chest pain, palpitations, fatigue, lack of energy, and fainting. It is diagnosed by tests like ECG. Treatment options for bradycardia depend upon the underlying causes. In cases of emergency oxygen supplementation and transvenous pacing is done. In case of non-cardiac etiology, the underlying condition is treated. In the case of sinus node dysfunction, the option of pacemaker is considered. In people with diabetes, lower sugar levels causing hypoglycemia has an adverse effect on their heart rates. During episodes of hypoglycemia that occur while someone is asleep, the heart rates plummet to dangerously low levels. This is can be a high cardiovascular risk. Diabetes can also induce bradycardia when the sugar levels are low, especially during the nights. It is even known to increase the risk of bradycardia in people with type 1 diabetes who take multiple insulin injections daily.