Trajkov Ivan, Kovacevic Dejan, Boskov Vladimir, Poposka Lidija, Gjorgov Nicola
Institute for Heart Diseases, Clinical Medical Centre, Medical Faculty, Skopje, R. Macedonia.
Prilozi. 2006 Jul;27(1):113-20.
Atrio-ventricular node reentry (AVNRT) is typically induced with an anterograde block over the fast pathway (FP) and conduction over the slow pathway (SP), with subsequent retrograde conduction over the FP. Rarely, a premature atrial complex (PAC) conducts simultaneously over the FP and SP to induce AVNRT. Previous publications have reported that conduction over the fast and slow pathway of the atrioventricular node can occur successively one after the other, thus leading to dual ventricular depolarization from what initially was a single atrial impulse. We report a case of an 18-year-old male patient referred for repeated bursts of ectopic activity. Evaluation of the patient's electrocardiographic recordings suggested the presence of dual ventricular activations for each atrial beat. The electrophysiological study revealed that the patient had simultaneous conduction over the fast and slow pathways of the atrioventricular node giving rise to a non-reentrant tachycardia, along with an absence of retrograde (ventriculoatrial) conduction, and a significant atrio-His bundle jump (A-H jump) through the slow pathway from the fast pathway during programmed electrical stimulation from the right atrium. Ablation of the slow pathway at the base of the Koch triangle yielded a cessation of the dual ventricular response, absence of the nonreentrant tachycardia and no A-H jump.
房室结折返（AVNRT）通常是在快速径路（FP）发生前向阻滞且激动沿慢速径路（SP）下传，随后激动沿FP发生逆向传导的情况下诱发的。很少见的是，房性早搏（PAC）同时沿FP和SP下传从而诱发AVNRT。既往文献报道，房室结快速径路和慢速径路的传导可相继发生，从而导致最初由单个心房冲动引起的双心室去极化。我们报告一例18岁男性患者，因反复出现异位活动发作前来就诊。对该患者心电图记录的评估提示每个心房搏动均存在双心室激动。电生理研究显示，该患者房室结快速径路和慢速径路同时发生传导，引发了一种非折返性心动过速，同时不存在逆向（室房）传导，并且在右心房程控电刺激期间，激动从快速径路经慢速径路出现明显的房希氏束间期跳跃（A-H跳跃）。在Koch三角底部消融慢速径路后，双心室反应消失，非折返性心动过速终止，且A-H跳跃消失。
