A slow heart rate of 30 to 40 beats per minute in the elderly is usually associated with sinus bradycardia, sinus node lesions, and heart block. 1. Sinus bradycardia: mainly refers to a heart rate of less than 60 beats per minute, usually associated with high vagal tone, and some patients are due to metabolic abnormalities. 2. Sinus node lesions: usually associated with myocardial ischemia and myocarditis, these factors can cause lesions in the sinus node, resulting in a slow heart rate. 3. Heart block: It mainly includes sinus atrial block, atrioventricular block, etc., which may cause heart rate to slow down, and the heart rate is lower than the normal range. Slow heart rate in the elderly, need to pay attention to rest, reduce myocardial oxygen consumption, while actively treating the primary disease, if the heart rate continues to decline, panic, shortness of breath, chest tightness, dizziness and other symptoms, need to consult a doctor in time and under the guidance of the physician to give atropine to improve the heart rate, and if necessary, to install a pacemaker to prevent sudden cardiac arrest.