Tachycardia of more than 100 per minute belongs to tachycardia, if it is physiological, it is normal; if it is pathological, it is abnormal. Physiological tachycardia mainly occurs after strenuous exercise, emotional excitement, drinking alcohol, after drinking coffee, generally remove the causative factors quickly return to normal. Pathologic tachycardia, also known as tachyarrhythmia, is abnormal. Common types include atrial fibrillation, paroxysmal supraventricular tachycardia, and preexcitation syndrome. 1. Atrial Fibrillation: The regular electrical activity of the atria is replaced by fast and disorderly atrial fibrillation waves, which manifests as a fast and irregular heart rhythm. Common clinical symptoms include palpitations, dizziness, chest tightness, fatigue, and even angina pectoris and heart failure. 2. Paroxysmal supraventricular tachycardia: It is a rapid and regular arrhythmia originating from the ventricular branches of the cardiac conduction system, characterized by sudden onset and sudden stop. Patients may have chest tightness, palpitations, and if the rapid heart rate leads to heart pumping dysfunction, fainting and sudden death may occur. 3. Pre-excitation syndrome: It refers to the fact that in addition to the normal conduction pathway between the atria and the ventricles, there are one or more additional pathways, and the electrical signals are transmitted along the abnormal pathway, causing tachyarrhythmia. Patients may have paroxysmal palpitations and chest tightness, and may also experience cardiac insufficiency and syncope. When tachyarrhythmia occurs, patients should go to the hospital in time for relevant examinations to clarify the type of arrhythmia and choose the appropriate treatment plan according to the condition.