Most of the ECG type b ventricular preexcitation is not serious, and a few patients will have tachyarrhythmias, which are more severe. Pre-excitation syndrome is mostly caused by congenital developmental anomalies, in which the patient has abnormal conduction within the myocardium, and type b ventricular pre-excitation is a type of pre-excitation syndrome. Most patients with preexcitation syndrome have a relatively stable condition and can live their entire lives without any symptoms. Their condition is relatively stable and does not require any special treatment. A small number of patients with preexcitation syndrome may develop tachyarrhythmias, such as paroxysmal supraventricular tachycardia, which can increase the severity of the condition. Some patients may develop preexcitation syndrome with atrial fibrillation, which is a very dangerous condition with a risk of inducing ventricular fibrillation, and it is important to terminate episodes quickly after onset. Patients with preexcitation syndrome should be followed up regularly, and those with symptoms should go to the hospital in time to be treated aggressively under the guidance of a physician.