Schatz J, Krongrad E, Malm J R
Circulation. 1976 Dec;54(6):1010-3. doi: 10.1161/01.cir.54.6.1010.
A patient with tricuspid atresia and characteristic electrocardiographic features of counterclockwise and superiorly oriented frontal plane QRS loop (left anterior hemiblock) is presented. Operative intervention resulted in a clockwise and inferior rotation of the frontal QRS loop (left posterior hemiblock) without the development of complete left bundle branch block. This observation suggests that the electrocardiographic pattern of left anterior hemiblock may result from other mechanisms in addition to block of the left bundle branch fibers oriented toward the anterior part of the left ventricle. The case further suggests that electrocardiographic patterns of apparent A-V conduction defects may not be at all associated with true block in the A-V conduction system. Further, it emphasizes the fact that various electrophysiologic mechanisms may account for identical electrocardiographic patterns.
本文报告了一名患有三尖瓣闭锁且具有逆时针和额面QRS环向上特征性心电图表现（左前分支阻滞）的患者。手术干预导致额面QRS环顺时针和向下旋转（左后分支阻滞），且未发展为完全性左束支传导阻滞。这一观察结果表明，左前分支阻滞的心电图模式可能是由除左束支纤维向左心室前部传导阻滞之外的其他机制导致的。该病例进一步表明，明显的房室传导缺陷的心电图模式可能与房室传导系统中的真正阻滞毫无关联。此外，它强调了各种电生理机制可能导致相同心电图模式这一事实。
