In search of the arrhythmogenic grey zone within myocardial scar using late gadol

描述（由申请人提供）：室性心动过速（VT）和纤颤（VF）是冠状动脉疾病（CAD）患者心源性猝死（SCD）的主要原因。VT/VF的来源被认为是瘢痕心肌内的致瘤基质，产生易于折返性室性快速性心律失常的区域。晚期钆增强（LGE）心血管MR（CMR）是体内识别心肌瘢痕的无创金标准，但其在治疗或VT患者风险分层中的临床价值仍不确定。LGE CMR已被用于识别包含活细胞和纤维化（组织异质性）的混合物的区域，称为“灰色区域”（GZ）（也称为“梗塞周围区”或“梗塞边缘区”）。大量研究表明，GZ体积比瘢痕体积更能预测VT的发生和死亡。我们的假设是，更准确地识别GZ是可能的，这将增加LGE预测心律失常、SCD风险分层和识别VT消融的心律失常边界区的能力。我们建议使用高空间分辨率的LGE来解决复杂的疤痕形态，和T1映射定量识别GZ。反对比LGE，其中GZ是明亮的，疤痕是黑暗的，突出了疤痕核心内的GZ。CMR方法，以更好地分类GZ将被应用到动物研究的组织病理学相关性，和VT患者的初步研究。

DESCRIPTION (provided by applicant): Ventricular tachycardia (VT) and fibrillation (VF) are a major cause of sudden cardiac death (SCD) in those with coronary artery disease (CAD). The source of VT/VF is believed to be the arrhythmogenic substrate within scarred myocardium, creating areas prone to reentrant ventricular tachyarrhythmia. Late gadolinium enhancement (LGE) cardiovascular MR (CMR) is the non-invasive gold standard for in-vivo identification of myocardial scar, but its clinical value in treatment or risk stratifying VT patients remains uncertain. LGE CMR has been employed to identify areas which contain a mixture of living cells and fibrosis (tissue heterogeneity), called the 'grey zone' (GZ) (a.k.a. 'peri-infarct zone' or 'arrhythmic border zone'). Numerous studies have shown that the volume of GZ, much more powerfully than the volume of scar, predicts inducibility of VT and arrhythmic death. Our hypothesis is that more accurate identification of GZ is possible, and will increase the power of LGE to predict arrhythmia, risk-stratify for SCD, and identify the arrhythmic border zone for VT ablation. We propose using high spatial resolution LGE to resolve complex scar morphology, and T1- mapping for quantitative identification of GZ. Reverse-contrast LGE, by which GZ is bright and scar is dark, highlights GZ within the scar core. The CMR methods to better classify GZ will be applied to an animal study for histopathological correlation, and a pilot study of VT patients.