在频率依赖性束支传导阻滞中,慢频率依赖性束支传导阻滞较为少见,当发生Ⅲ°一型房室传导阻滞时,须与室性逸搏和Ⅱ°二型阻滞鉴别,后两者更易产生宽QRS综合波,因Ⅱ°二型A-VB预后较差,多数人需安装起搏器治疗,故两者鉴别有着十分重要的意义。本例Ⅱ°A-VB初看认为是Ⅱ°二型伴左束支传导阻滞,但仔细观察,更符合Ⅱ°一型A-VB伴慢频率依赖性束支传导阻滞,后经电生理检查证实希氏束远端无传导异常。患者男性,45岁。既往有高血压病史伴严重胸痛住院,心电图曾示Ⅱ、Ⅲ、aVF导联ST抬高3mm,Ⅲ、aVF导联出 In frequency-dependent bundle branch block, the slow frequency-dependent bundle branch block is less common and should be distinguished from ventricular arrhythmia and type II ¢ ò block when type III ¢ ò-atrioventricular block occurs , The latter two are more likely to produce wide QRS complex, because Ⅱ ° A-type VB-Ⅱ poor prognosis, most people need to install pacemaker treatment, so the identification of the two is of great significance. This case Ⅱ ° A-VB at first thought to be Ⅱ ° two with left bundle branch block, but carefully observed, more in line with Ⅱ ° a type A-VB with slow frequency-dependent bundle branch block, after the electricity Physiological examination confirmed that there was no conduction abnormalities in the distal bundle of His bundle. Male patient, 45 years old. Past history of hypertension with severe chest pain hospitalized, ECG showed Ⅱ, Ⅲ, aVF lead ST elevation 3mm, Ⅲ, aVF lead