异丙肾上腺素对射频消融房室结折返性心动过速疗效评价的意义

对消融房室结慢径的７２例房室结折返性心动过速（ＡＶＮＲＴ）病人进行观察分析，以了解异丙肾上腺素在ＡＶＮＲＴ射频消融中的临床价值。消融前电生理检查时有２７．８％（２０／７２）的病人未能诱发ＡＶＮＲＴ，静脉滴注异丙肾上腺素后，８５．０％（１７／２０）则能诱发；消融后４７．９％（３４／７２）用异丙肾上腺素评价，其中８例既有房室结跳跃现象又有心房回波的病人５０．０％（４／８）诱发出ＡＶＮＲＴ而重新消融。随访８．５±４．３个月，成功消融的７１例中，３４例经异丙肾上腺素评价者无一例复发，３７例未用异丙肾上腺素评价者２例复发。提示静脉滴注异丙肾上腺素可提高ＡＶＮＲＴ的诱发率；消融后房室结慢径前传功能存在时，无论有无心房回波均应用异丙肾上腺素评价，以确定消融终点和降低复发率。

The Effect of Isoproterenol for Radiofrequency Catheter Ablation of Atrioventricular Nodal Reentrant Tachycardia

To assess the value of infusion of isoproterenol for induction of atrioventricular nodal reentrant tachycardia(AVNRT),endpoint of ablation of AVNRT and recurrence after successful ablation of AVNRT,72 patients (male 25,Female 47) with AVNRT aged 49.7±13.7 years were underwent select ablation of slow pathway.Before ablation of slow pathway,AVNRT was induced by burst or programmed stimuli in 72.2%(52/72) patients with AVNRT during basic electrophysiologic study.AVNRT was induced in 85%(17/20) patients in whom AVNRT could not be induced during basic condition during infusion of isoproterenol with 1～3 μg/min (increased 25%～30% heart rate of basic condition).After ablation of slow pathway,electrophysiologic study was repeated in 34 patients during infusion of isoproterenol in whom AVNRT was only induced during infusion of isoproterenol before ablation or antergrade conduction of slow pathway still existed and a single atrial echo occurred.AVNRT was induced in 50%(4/8) patients with antergrade conduction and a single atrial echo.During 8.5±4.3 months of following up,no recurrence of AVNRT was found in 34 patients with assessment of infusion of isoproterenol after ablation of slow pathway,but recurrence of AVNRT occurred in 5.4%(2/37) patients without assessment of infusion of isoproterenol after ablation of slow pathway.Conclusions:(1)The rate of induced AVNRT could be increased by infusion of isoproterenol during electrophysiologic study.(2)Accessment of infusion of isoproterenol should be performed in the patients with antergrade conduction of slow pathway and a single atrial echo.