阵发性室上性心动过速发生周长变化的临床观察

The clinical observation of cycle length change during tachycardia in patients with paroxysmal supraventricular tachycardia

目的探讨阵发性室上性心动过速患者心动过速发作过程中,心动过速周长发生变化的特征及相关机制。方法回顾性分析2019年1月至2021年1月收治的阵发性室上性心动过速并行射频消融治疗的患者254例。所有患者术中均诱发出心动过速。心动过速发作时周长发生大于30 ms以上的改变并持续2 min以上定义为周长变化。结果在254例患者中,12例术中发生心动过速周长变化,发生率为4.72%。周长变化表现为节律整齐的变化和节律完全不整齐的变化。8例周长变化整齐,其中2例为旁道合并同侧束支阻滞,4例为多旁道折返环改变,其余2例为房室结多径路折返环改变。4例周长变化不整齐,1例为右侧递减旁道参与的房室折返性心动过速,1例为左侧旁道消融后二尖瓣峡部不完全阻滞,2例为房室结折返性心动过速。结论阵发性室上性心动过速可伴随发生周长的改变,弄清周长改变的原因有助于明确诊断,指导消融。

Objective To investigate the electrophysiologic characteristic and possible mechanism of cycle length(CL)changes during reciprocating tachycardia in patients with paroxysmal supraventricular tachycardia.Methods This study included 254 patients consecutive patients with paroxysmal supraventricular tachycardia who underwent electrophysiologic study and radiofrequency ablation in Guizhou Provincial People′s Hospital from January 2019 to January 2021.After determination of baseline electrophysiologic measurements,tachycardia was induced by either atrial or ventricular pacing.CL changes were considered as significant when the changes were more than 30 msec and maintained for at least 2 minutes.Results We reviewed data of 254 consecutive patients with paroxysmal supraventricular tachycardia,significant CL changes during reciprocating tachycardia were found in 12(4.72%).Out of 12 patients,the tachycardia showing completely irregular rhythm were found in four patients,the remain 8 patients showed regular rhythm.In 4 patients with completely irregular rhythm,two patients were accessory pathway and the other two patients were atrioventricular nodal reentrant tachycardia.Of the eight patients with regular rhythm,two patients was accessory pathway combined with ipsilateral bundle branch block during tachycardia,4 patients were multiple accessory pathway,and the other 2 patients had triple or more anterograde AV node pathway.Conclusions CL changes during reciprocating tachycardia are not uncommon in patients with paroxysmal supraventricular tachycardia.Awareness of several different mechanisms responsible for CL changes may avoid misinterpretation of electrophysiological characteristics.