Grant Elena K, Berul Charles I, Cross Russell R, Moak Jeffrey P, Hamann Karin S, Sumihara Kohei, Cronin Ileen, O'Brien Kendall J, Ratnayaka Kanishka, Hansen Michael S, Kellman Peter, Olivieri Laura J
Department of Cardiology, Children's National Health System, Washington, District of Columbia, USA.
Division of Intramural Research, Cardiovascular and Pulmonary Branch, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA.
J Cardiovasc Electrophysiol. 2017 May;28(5):517-522. doi: 10.1111/jce.13197. Epub 2017 Mar 28.
Arrhythmia ablation with current techniques is not universally successful. Inadequate ablation lesion formation may be responsible for some arrhythmia recurrences. Periprocedural visualization of ablation lesions may identify inadequate lesions and gaps to guide further ablation and reduce risk of arrhythmia recurrence.
This feasibility study assessed acute postprocedure ablation lesions by MRI, and correlated these findings with clinical outcomes. Ten pediatric patients who underwent ventricular tachycardia ablation were transferred immediately postablation to a 1.5T MRI scanner and late gadolinium enhancement (LGE) imaging was performed to characterize ablation lesions. Immediate and mid-term arrhythmia recurrences were assessed.
Patient characteristics include median age 14 years (1-18 years), median weight 52 kg (11-81 kg), normal cardiac anatomy (n = 6), d-transposition of great arteries post arterial switch repair (n = 2), anomalous coronary artery origin post repair (n = 1), and cardiac rhabdomyoma (n = 1). All patients underwent radiofrequency catheter ablation of ventricular arrhythmia with acute procedural success. LGE was identified at the reported ablation site in 9/10 patients, all arrhythmia-free at median 7 months follow-up. LGE was not visible in 1 patient who had recurrence of frequent premature ventricular contractions within 2 hours, confirmed on Holter at 1 and 21 months post procedure.
Ventricular ablation lesion visibility by MRI in the acute post procedure setting is feasible. Lesions identifiable with MRI may correlate with clinical outcomes. Acute MRI identification of gaps or inadequate lesions may provide the unique temporal opportunity for additional ablation therapy to decrease arrhythmia recurrence.
采用当前技术进行心律失常消融并非总能成功。消融损伤形成不充分可能是某些心律失常复发的原因。围手术期对消融损伤进行可视化检查可能会发现不充分的损伤和间隙，以指导进一步消融并降低心律失常复发风险。
本可行性研究通过磁共振成像（MRI）评估术后急性期的消融损伤，并将这些结果与临床结局相关联。10例接受室性心动过速消融的儿科患者在消融后立即被转运至1.5T MRI扫描仪处，并进行延迟钆增强（LGE）成像以表征消融损伤。评估即刻和中期心律失常复发情况。
患者特征包括年龄中位数14岁（1 - 18岁），体重中位数52千克（11 - 81千克），心脏解剖结构正常（n = 6），大动脉转位动脉调转修复术后（n = 2），修复术后冠状动脉起源异常（n = 1），以及心脏横纹肌瘤（n = 1）。所有患者均接受了室性心律失常的射频导管消融，手术即刻成功。9/10的患者在报告的消融部位发现有LGE，随访中位数7个月时均无心律失常。1例患者在术后2小时内频繁室性早搏复发，术后1个月和21个月的动态心电图证实了这一点，该患者未发现LGE。
在术后急性期通过MRI观察心室消融损伤是可行的。MRI可识别的损伤可能与临床结局相关。通过急性MRI识别间隙或不充分的损伤可能为额外的消融治疗提供独特的时机，以减少心律失常复发。
