流出道室间隔肌壁内起源室性心律失常心电图特点与射频消融

摘要

目的：分析流出道室间隔肌壁内起源特发性室性心律失常（IVAs）的心电图特征及导管消融体会。方法：对87例IVAs患者在Ensite三维标测系统指导下行导管射频消融的临床资料进行回顾性分析。结果：87例行导管射频消融术的IVAs患者，经激动和起搏标测，7例（8%）IVAs于心大静脉穿间隔支内标测证实起源点位于流出道室间隔肌壁内，心电图表现为左束支传导阻滞伴电轴向下图形。因消融导管无法通过心大静脉穿间隔支到达起源部位，选择在与起源点相对应的心内膜最早激动处进行消融，均未获得即刻成功；其中2例在随访3月内室早频率较前减少80%，获得远期成功。该起源部位IVAs的某些心电图和标测特征不同于其它部位起源。结论：流出道室间隔肌壁内起源IVAs某些心电图特征可帮助识别此类心律失常，并有助于指导导管消融标测，但消融成功率低。%Objective: To explore the characteristics of electrocardiography ( ECG) and the clinical effect on idiopathic ventricular arrhythmias ( IVAs) originating from the interventricular septum. Methods:The characteristics of ECG and clinical results of the Ensite mapping system under catheter ablation were analyzed in 87 patients with IVAs. Results:In a consecutive group of 87 patients with IVAs referred for ablation, the site of origin for ventricular arrhythmias was assessed by activation mapping and pace-mapping. In 7 out of 87 patients (8%), an intramural focus in the interventricular septum was identified. All intramural ventricular arrhythmias manifested left bundle-branch block morphology with inferior axis. Due to the inaccessibility of the ablation catheter to the site via the venous system, radiofrequency energy was transmitted to the endocardial site where the earliest activations were recorded. Immediate success was not acquired in 7 patients;however, an 80%reduction of premature ventricular beats was found in 2 patients during the follow-up. ECG and mapping characteristics of the patients with intramural septal inventricular arrhythmias were different from those originating from other sites. Conclusion: Idiopathic septal ventricular arrhythmias may originate from interventricular septum. The distinctive ECG characteristics of IVAs can contribute to catheter mapping and ablation, but with lower success rate.