Fishberger Steven B, Olen Melissa M, Rollinson Nancy L, Rossi Anthony F
Division of Cardiology, Miami Children's Hospital, Miami, Florida; Division of Pediatric Cardiology, Yale-New Haven Medical Center, New Haven, Connecticut.
Pacing Clin Electrophysiol. 2015 Feb;38(2):209-15. doi: 10.1111/pace.12551. Epub 2014 Dec 2.
Catheter ablation of idiopathic left ventricular tachycardia in the pediatric population remains challenging. A recent multicenter study reported limited success with 14% not undergoing ablation due to inability to induce ventricular tachycardia (VT) or blood pressure instability during tachycardia. Creating complete or partial fascicular block with radiofrequency catheter ablation is a technique that may eliminate VT. This approach is performed during sinus rhythm, enabling atrioventricular conduction monitoring and maintaining stable hemodynamics. Importantly, induction of VT is not necessary for mapping or assessing efficacy of the procedure.
A retrospective review of pediatric patients (3-17 years) with recurrent, documented idiopathic left ventricular tachycardia by electrocardiogram who received catheter ablation by creating fascicular block as a therapeutic endpoint was performed. All had ablation at the site of an identified Purkinje potential.
There were six patients with idiopathic left ventricular tachycardia, five originating from the posterior fascicle and one from the anterior fascicle. VT was not induced or spontaneous in four patients using programmed stimulation and isoproterenol infusion. All patients had a QRS axis shift following ablation, though none met criteria for fascicular block. At follow up (7-49 months, mean 27 months), all patients had persistence of this shift. There were no recurrences of VT and none of the patients were taking antiarrhythmic medication.
The technique of creating partial fascicular block appears to be a safe and effective approach to ablation of idiopathic left ventricular tachycardia in children.
小儿特发性左室性心动过速的导管消融仍然具有挑战性。最近一项多中心研究报告显示成功率有限，14%的患者因无法诱发室性心动过速（VT）或心动过速期间血压不稳定而未接受消融。通过射频导管消融造成完全或部分束支阻滞是一种可能消除VT的技术。该方法在窦性心律期间进行，能够监测房室传导并维持稳定的血流动力学。重要的是，诱发VT对于该手术的标测或评估疗效并非必需。
对通过心电图记录有复发性特发性左室性心动过速且接受以造成束支阻滞作为治疗终点的导管消融的小儿患者（3至17岁）进行回顾性研究。所有患者均在已识别的浦肯野电位部位进行消融。
有6例特发性左室性心动过速患者，5例起源于后束支，1例起源于前束支。4例患者使用程序刺激和异丙肾上腺素输注后未诱发VT或无自发VT。所有患者消融后均出现QRS电轴偏移，尽管无1例符合束支阻滞标准。随访（7至49个月，平均27个月）时，所有患者均持续存在这种偏移。无VT复发，且无患者服用抗心律失常药物。
造成部分束支阻滞的技术似乎是小儿特发性左室性心动过速消融的一种安全有效的方法。
