The slow heart rate of about 45 beats per minute may be physiological slowing of the heart rate, or it may be pathologic, which is common in coronary heart disease, cardiomyopathy, arrhythmia, electrolyte metabolism disorders, digitalis intoxication and so on. If the former does not need special treatment, if the latter need to treat the cause and symptomatic treatment at the same time. Normal heart rate is 60~100 beats per minute, below 60 beats/minute belongs to bradycardia. 1. Physiologic slowing of the heart rate can be seen in the elderly, athletes, or in normal people at night during sleep. These cases of heart rate slowing will not have obvious symptoms, and usually will not be lower than 40 beats / minute. There is no need for special treatment, regular ECG or heart rate monitoring can be done, if there are uncomfortable symptoms, you need to go to the hospital. 2. Pathological factors, commonly found in coronary heart disease, cardiomyopathy, arrhythmia, electrolyte metabolism disorders, digitalis poisoning. It can cause symptoms of chest tightness, dizziness, weakness, and can be given to enhance the heart rate of drugs, such as epinephrine, atropine, etc.; if the effect of drug treatment is poor, for serious bradycardia or frequent fainting patients, need to be implanted with a pacemaker treatment. If there is a slow heart rate and you cannot identify the cause or have clinical symptoms, you should go to the cardiology department of the hospital for treatment.