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)是冠心病(CAD)患者心源性猝死(SCD)的主要原因。VT/VF的来源被认为是疤痕心肌内致心律失常的底物，造成易发生折返性室性快速性心律失常的区域。晚期Gd增强(LGE)心血管MR(CMR)是无创性的在体识别心肌瘢痕的金标准，但其在VT患者治疗或危险分层中的临床价值仍不确定。LGE CMR已被用来识别含有活细胞和纤维化(组织异质性)的混合区域，称为灰色地带(GZ)(也称为。梗塞周围区“或”心律失常交界区“)。大量研究表明，GZ的体积比疤痕的体积更能预测VT的诱发性和心律失常死亡。我们的假设是，更准确地识别GZ是可能的，这将增加LGE预测心律失常的能力，对SCD进行风险分层，并识别室速消融的心律失常交界区。我们建议使用高空间分辨率的LGE来解析复杂的瘢痕形态，并使用T1映射来定量识别GZ。对比度相反的LGE，GZ是明亮的，SCAR是暗色的，突出了SCAR核心内的GZ。CMR方法将更好地对GZ进行分类，并将用于组织病理学相关性的动物研究和VT患者的初步研究。 与公共卫生相关：室性心动过速是一种常见的心律失常，几乎占心脏病死亡人数的一半。心律失常的原因通常是心脏病发作后心脏肌肉上的疤痕，这会改变心脏内的电信号。我们将研究如何使用心脏核磁共振来检测心脏上可能导致心律失常的疤痕。

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. PUBLIC HEALTH RELEVANCE: Ventricular tachycardia is a common arrhythmia, responsible for almost half of deaths due to heart-disease. The cause of the arrhythmia is often scar in the heart muscle after a heart-attack, which changes the electrical signals within the heart. We will study ways to use cardiac MRI to detect scar in the heart which may result in an arrhythmia.