心肌梗死后室性心律失常电风暴射频导管消融治疗

Radiofrequency catheter ablation of ventricular premature contractions to treat ventricular electrical storm after myocardial infarction

目的报道经射频导管消融治疗心肌梗死(MI)后血运重建和抗心律失常药物治疗无效的室性心律失常电风暴2例。方法 2例病人为男性,64岁和73岁。前壁 MI 后出现反复发作室性心动过速(室速)或心室颤动(室颤),经血运重建、抗心律失常药物等治疗室速、室颤仍反复发作。2例患者室速、室颤均由呈右束支阻滞(RBBB)图形室性早搏(室早)所诱发。标测和消融方法为在左心室内标测室早时最早激动部位后进行射频消融。结果 2例均可记录到频发呈 RBBB 图形室早,在2例患者中室早均可诱发室速,与临床诱发方式相同。左心室内激动标测显示2例呈 RBBB 伴心电轴左偏形态的室早的最早激动部位在中下间隔,室早时浦肯野纤维电位提前体表心电图 QRS 波均为50 ms,窦性心律时在同一部位也可记录到清晰的浦肯野电位,2例分别放电6次和8次,均成功消融室早。2例分别随访49个月和4个月,无室速和室颤复发。结论 MI 后室性心律失常电风暴可能由起源于左心室浦肯野纤维网的室早所诱发,经射频导管消融 MI 后药物和血运重建等治疗无效的电风暴有较好的效果。

Objective To report the mapping and ablation of drug-refractory ventricular electrical storm after myocardial infarction （MI） in 2 patients. Methods Two male patients （ age 64 and 73 years） with recurrent episodes of ventricular tachycardia （VT） or ventricular fibrillation （VF） after anterior wall MI despite revascularization and antiarrhythmic drugs were studied. Both patients demonstrated frequent ventricular premature beats （VPBs） initiating monomorphic or polymorphic VT, or VF. Left ventricular （LV） mapping was performed to identify the earliest site of VPB activity and radiofrequency ablation of the triggering VPBs was attempted. Results VPBs with a right bundle branch block morphology （RBBB） were identified to initiate VT in both patients, and frequent VPBs allowed VPB mapping and ablation. Activation mapping of the clinical VPBs demonstrated the earliest activation in the inferomedial LV in both patients. Purkinje-like potential was recorded that preceded the onset of each extrasystole by a maximum of 50 ms in both patients. At the same site, a Purkinje potential was documented that preceded the onset of the QRS complex during sinus rhythm. Six to 8 RF applications abolished local Purkinje potentials at the site of earliest activation and suppressed VPBs in the 2 patients. Additional 5 RF applications were performed to ablate the anteromedial LV in the second patient because of another morphology of VPBs. No episode of ventricular tachycardia or fibrillation has recurred during 49 and 4 months follow-up in both patients, respectively. Condnsions Frequent ventricular tachyarrhythmias after MI may be triggered by VPBs originating from LV Purkinje network. Catheter ablation of the triggering VPBs may be used as a bailout therapy in these patients to cure drug-resistant electrical storm.