预激症候群(PES),又称 W—P—W 综合征,PES 的病人容易并发阵发性心动过速,发生率约在50—80%,以室上性心动过速为常见,其次是心房颤动,心房搏动较少见,严重者可致心室颤动.一.PES 致阵发性心动过速的类型及机制PES 时在房室之间存在着正常房室传导系统和异常旁道束,两者有不同的不应期和不同的传导速度。PES 有下列三个条件即可出现阵发性心动过速:1、由房性、连接处性或室性过早搏动引起心 Pre-emptive syndrome (PES), also known as W-P-W syndrome, PES patients prone to paroxysmal tachycardia, the incidence of about 50-80%, supraventricular tachycardia is common, followed by Atrial fibrillation, atrial fibrillation less common, severe cases can cause ventricular fibrillation.PES induced paroxysmal tachycardia type and mechanism of PES exist in the atrioventricular chamber between the normal atrioventricular conduction system and abnormal bypass tract, Both have different refractory periods and different conduction velocities. PES paroxysmal tachycardia can occur under the following three conditions: 1, caused by atrial, junctional ventricular premature ventricular heart or heart