Wentzler’s phenomenon mainly refers to the gradual slowing down of conduction in a certain part of the cardiac conduction system, finally leading to conduction interruption, and the causes can be classified as pathologic or drug-induced. There is also a physiological Wen’s phenomenon caused by increased heart rate or vagal influence, which is more common in the atrioventricular (AV) junction area, and is usually temporary, sometimes due to changes in body position, respiration, and heart rate, and a few may form a permanent phenomenon. Among the conduction blocks, second-degree atrioventricular block is divided into two types, in which second-degree type I is Wen’s phenomenon, which is mainly manifested by the gradual prolongation of PR interval, and finally the atria are completely blocked, resulting in the absence of the QRS wave group after the P wave and causing the ventricular leakage, and the shortening of the first PR interval after ventricular leakage, with a cyclic pattern of changes. This type of AV nodal area has a prolonged absolute response period, while the relative response period is close to normal, so the prognosis is relatively good.