The causes of fast heartbeat in the evening include physiological phenomenon, arrhythmia, cardiomyopathy and so on. 1. Physiological phenomenon: due to physical fatigue, mental stress, tension and anxiety, etc., the sympathetic excitability of the patient in the evening increases significantly, resulting in regulatory disorders, causing the patient to have a fast heartbeat. 2. Arrhythmia: if the patient himself suffers from arrhythmia, due to the ectopic pacemaker has been in the state of excitement, resulting in the heart has been in the state of excitement, resulting in the sympathetic nerves, vagus nerves can not control the heartbeat, causing the patient to appear fast heartbeat symptoms. 3. Cardiomyopathy: If the patient suffers from cardiomyopathy, it is easy to induce heart failure, especially at night, this phenomenon will be aggravated. When heart failure occurs, the rhythm of the heart will be irregular, which will lead to the symptoms of rapid heartbeat. If the patient experiences rapid heartbeat in the evening, it is recommended that the patient go to the hospital in time. Improve the ECG, 24-hour ECG, cardiac ultrasound and other tests to clarify the cause of the disease and follow the doctor’s instructions for treatment.