隐匿性旁路与房室结折返性心动过速鉴别诊断的临床研究

Clinical study of differential diagnosis in concealed accessory pathway vs atrioventricular node reentrant tachycardia

目的观察经校正的心室起搏拖带起搏后间期(PPI)与心动过速周长(TCL)差值,在隐匿性旁路介导的顺向房室折返性心动过速(O-AVRT)与房室结双径路所致房室结折返性心动过速(AVNRT)鉴别诊断中的价值。方法选择经心内电生理检查和射频消融的65例室上速心动过速患者,窦律时无预激波出现。其中AVNRT37例、O-AVRT28例,以快于心动过速频率5～15次/min的刺激频率进行心动过速拖带,比较校正的心室起搏拖带的PPI与TCL差值等参数在这两组中的差异。结果心内电生理检查发现,28例O-AVRT和37例AVNRT患者,除2例AVNRT患者外均成功拖带,28例O-AVRT患者校正的PPI-TCL差值[(68±20)ms]短于35例AVNRT患者校正的差值[(151±16)ms,P<0.01]。所有O-AVRT患者校正的PPI-TCL差值均<110ms,而AVNRT患者的差值均>110ms。间隔部旁路患者校正的PPI-TCL差值比游离壁旁路患者更短一些。结论经校正的PPI-TCL差值测定是一项快速、有效的鉴别AVNRT和隐匿性O-AVRT的方法,对射频消融具有重要的指导意义;校正的PPI-TCL差值<110ms对确诊O-AVRT患者能提供更大的判断价值。

Objective To determine whether the corrected difference of Postpaceing interval（PPI） between tachycardia cycle length （TCL） after entrainment of tachycardia during ventricular stimulation and para-Hisian pacing are useful, simple maneuvers in differentiating AV nodal reentrant tachycardia （AVNRT） from orthodromic reciprocating tachyeardia （ORT） using a concealed accessory pathway. Methods A total of 65 regular paroxysmal supraventricular tachycardia patients who did not show preexcitation during sinus rhythm were enrolled. All of them underwent electrophysiological study and ablation.37 patients diagnosed AVNRT and the rests （28 patients） diagnosed O-AVRT.Tachycardia entrainment was attempted through trains of 5-15 fight ventricular apex pacing pulses. To compare the difference of the Postpaceing interval （PPI） between tachycardia cycle length （TCL） in the two groups. The increment in AV nodal conduction time in the first PPI was subtracted from the PPI-TCL difference （namely, corrected PPI-TCL）. Results Electrophysiological study demonstrated ORT in 28 patients and AVNRT in 35 patients. Transient entrainment was achieved in all but 2 patients. The mean corrected PPI-TCL difference was significantly shorter in the ORT patients （68±20）ms than that AVNRT patients （151±16）ms,P〈0.01. The presence of a corrected PPI-TCL difference〈110 ms was identified in the all ORT patients, and no patients with AVNRT had such a difference. Patients with septal accessory pathways had shorter corrected PPI-TCL difference than patients with free-wall accessory pathways. Conclusion The return cycle after tachycardia entrainment by right ventricular apex stimulation with correction for AV nodal delay is a rapid and useful maneuver for differential diagnosis of AVNRT or ORT in patients without preexcitation. The presence of a corrected PPI-TCL〈110 ms may accurately identify those patients with ORT.