The presence or absence of clinical symptoms of arrhythmias and the presentation of clinical symptoms are influenced by many factors, including the underlying health of the heart, the type and severity of the arrhythmia, the frequency, timing, and duration of the arrhythmia, and the sensitivity of the patient. Some arrhythmias may not produce any symptoms, and accordingly, the presence of common symptoms of arrhythmias such as spontaneous palpitations does not necessarily imply the presence of an arrhythmia. It is important to emphasize that the presence or absence of symptoms does not necessarily correlate with the severity of the arrhythmia, and treatment of arrhythmias should not be neglected because of the absence or mildness of symptoms. A large proportion of tachyarrhythmias and bradyarrhythmias overlap and cannot be distinguished from each other. Common arrhythmia symptoms include: weakness, shortness of breath, panic, profuse sweating, dark confusion, fainting. Severe arrhythmias such as ventricular flutter and ventricular fibrillation can manifest as sudden death, and some arrhythmias may have their complications as their first clinical manifestation, such as atrial fibrillation, which may manifest as stroke symptoms (coma, hemiparesis, etc.) when detected. Xinhua Wang, Department of Cardiology, Shanghai Renji Hospital