束支传导阻滞的心电图极为常见,它可表现为持久性或间歇性。频率依赖型束支传导阻滞是间歇性束支传导阻滞中最常见的一种,其发生与心率的增快或减慢密切相关。在心率增快时出现的称快频率依赖型束支传导阻滞(即三相阻滞),在心率减慢时出现的称慢频率依赖型束支传导阻滞(即四相阻滞)。现将三例报告如下,并对其产生机理略加讨论。 Electrocardiogram of bundle branch block is extremely common, it can be expressed as persistent or intermittent. Frequency-dependent bundle branch block is the most common intermittent bundle branch block, its occurrence and heart rate faster or slowed down are closely related. Frequency-dependent bundle branch block (ie, three-phase block), which occurs at increased heart rate, is referred to as a slow frequency-dependent bundle branch block (ie, four-phase block) when heart rate slows. Now report the three cases are as follows, and a slight discussion on the mechanism of its production.