心室起搏拖带对房室结折返性和间隔旁路参与的房室折返性心动过速的鉴别作用

目的　研究心动过速时心室起搏拖带对房室结折返性心动过速 (AVNRT )和间隔旁路参与的顺向型房室折返性心动过速 (间隔旁路ORT)的鉴别意义。方法　 30例AVNRT和 2 5例间隔旁路ORT病人在心动过速发生后 ,采用较心动过速的周长 (TCL)短 10～ 4 0ms的周长行右心室起搏拖带心动过速。测量右心室起搏之前的心室 心房 (VA)间期和TCL。停止起搏后 ,测量最后一次刺激信号至最后起搏拖带的心房激动 (SA)间期 ,以及起搏后间期 (PPI)。结果　所有 30例AVNRT病人的SA -VA间期 >85ms、PPI-TCL >115ms,而 2 5例ORT病人的SA -VA间期 <85ms、PPI-TCL <115ms。结论　PPI TCL和SA VA间期是鉴别AVNRT和间隔旁路ORT的非常可靠的指标 ,具有较高的特异性。

Differentiation of atrioventricular node reentrant tachycardia from orthodromic reciprocating tachycardia using a septal accessory pathway by ventricular pacing entraiment

Objective To determine whether the ventricular pacing entrainment during tachycardia is useful for differentiating atrioventricular node reentrant tachycardia (AVNRT) from orthodromic reciprocating tachycardia (ORT) using a septal accessory pathway. Methods In 30 patients with AVNRT and 25 patients with ORT using a septal accessory pathway, the right ventricle was paced at a cycle length 10 to 40 ms shorter than the tachycardia cycle length(TCL). The ventriculo-atrial(VA) interval and TCL were measured just before pacing. The interval between the last pacing stimulus and the last entrained atrial depolarization (SA interval) and the post-pacing interval(PPI) at the right ventricular apex were measured on cessation of ventricular pacing.Results All 30 patients with AVNRT and none of the 25 patients with ORT using a septal accessory pathway had an SA-VA interval>85 ms and PPI-TCL>115 ms.Conclusion The SA-VA interval and PPI-TCL are useful in distinguishing AVNRT from ORT using a septal accessory pathway.