Cardiac Magnetic Resonance Tissue Characterization of Ischemic and Non-Ischemic Myocardium to Predict Left Ventricular Functional Recovery and Outcomes after Multivessel Coronary Revascularization

项目摘要/摘要 缺血性左心室收缩功能障碍(ILVSD)是导致心力衰竭(HF)和死亡的主要原因。 风险最大的是多支冠状动脉疾病(CAD)患者。冠状动脉血运重建(REVASC) 提供了一种改善iLVSD的潜在方法，但反应高度可变。“生存能力”成像(区分 从可挽救的心肌梗死)被广泛吹捧为预测复跳反应的工具，但其 公用事业公司受到了最近的临床试验的挑战。观察到缺乏成像预测效用的一个原因 重建后左室功能恢复可能源于用于确定生存能力的成像方法：先前没有试验 在看似可行的区域引起收缩功能障碍、低灌注率或非缺血区- 心脏MRI(CMR)可以唯一地区分每一种病变。我们小组进行了单中心研究 显示心肌梗死的跨壁范围是重建后左心功能改善的有力预测指标；我们有 也显示低灌注率可预测不良的重塑和预后。我们的成员进行的技术研究 该小组已经开发出一种新的晚期Gd增强(LGE)CMR方法，该方法使用血液抑制 (“暗血”)，以更好地区分梗塞和血池-潜在地进一步提高生存能力，因为- 评估。目前尚不清楚REVASC策略对LV收缩恢复的不同影响是否与以下因素有关 梗塞或灌注表型，如果是非缺血基质(细胞外体积分数、心外膜或中壁 LGE)可改变血管紧张素转换酶的反应，如果左心室收缩功能恢复与改善预后相平行。要解决这些问题 关键知识差距，这项观察性研究将利用新启动的STICH3C试验-前瞻性 多中心临床试验比较经皮冠状动脉介入治疗(PCI)与手术治疗(CABG)治疗iLVSD和多梗死性心肌梗死的疗效 TIVEVER/左主CAD。在检查前(&lt；1个月)和检查后(12个月)在200个月内进行灌注CMR STICH3C患者，并通过中央核心实验室进行分析。我们的中心假设是心肌梗死的超壁性 (LGE)和低灌注率可预测再灌注后左室收缩反应(EF)和预后(QOL、HF、死亡率)。 VASC，冠状动脉旁路移植术与经皮冠状动脉旁路移植术对左心功能恢复的治疗效果与存活的心肌梗死患者的比例增加。 CMR显示心肌再灌流。Aim 1将检测心肌梗死跨室壁和低灌注率以预测左室 重建后恢复(改善的射血分数，应变)；Aim 2将评估非缺血组织基质 修改左心室收缩恢复的可能性；AIM 3将测试梗死、低灌注率和 重建后的非缺血基质，重点是残留的心肌组织特性作为持续的预测因素。 帐篷左心功能障碍、生活质量受损和临床事件(心力衰竭再入院、死亡率)。我们的团队提供 在关键项目相关领域的互补专业知识-翻译CMR研究、心脏手术、心力衰竭- URE和临床试验--以及卓有成效的协作记录。研究结果已做好转变的准备 评估生存能力的成像范例和持续性左心功能不全的提示机制 从而改善数百万iLVSD患者的治疗决策和临床结果。

PROJECT SUMMARY / ABSTRACT Ischemic left ventricular systolic dysfunction (iLVSD) is a leading cause of heart failure (HF) and death, for which risk is greatest in patients with multivessel coronary artery disease (CAD). Coronary revascularization (revasc) provides a potential means to improve iLVSD, but response is highly variable. “Viability” imaging (to differentiate infarcted from salvageable myocardium) had been widely touted as a tool to predict revasc response, but its utility has been challenged by recent clinical trials. One reason for observed lack of utility of imaging to predict LV functional recovery after revasc may stem from imaging approaches used to define viability: No prior trial has accounted for contractile dysfunction, hypoperfusion, or non-ischemic substrate in seemingly viable regions – each of which can be uniquely discerned by cardiac MRI (CMR). Our group has conducted single center studies showing transmural extent of infarction to be a powerful predictor of improved LV function after revasc; we have also shown hypoperfusion to predict adverse remodeling and prognosis. Technical research by members of our group has developed a new late gadolinium enhancement (LGE) CMR approach that uses blood suppression (“dark-blood”) to better discriminate between infarct and blood-pool – potentially further enhancing viability as- sessment. It is unknown if differential impact of revasc strategy on LV contractile recovery varies in relation to infarct or perfusion phenotype, if non-ischemic substrate (extracellular volume fraction, epicardial or mid-wall LGE) modifies revasc response, and if LV contractile recovery parallels improved prognosis. To address these critical knowledge gaps, this observational study will leverage the newly initiated STICH3C trial - a prospective multicenter trial comparing percutaneous (PCI) vs. surgical (CABG) revasc for patients with iLVSD and mul- tivessel/left main CAD. Perfusion CMR will be performed pre- (<1 month) and post-revasc (12 months) in 200 STICH3C patients and analyzed via a centralized core lab. Our central hypothesis is that infarct transmurality (LGE) and hypoperfusion will predict LV contractile response (EF) and prognosis (QOL, HF, mortality) after re- vasc, for which treatment effect of CABG vs. PCI on LV recovery will increase in proportion to viable but hy- poperfused myocardium on CMR. Aim 1 will test infarct transmurality and hypoperfusion for prediction of LV recovery (improved ejection fraction, strain) after revasc; Aim 2 will evaluate if non-ischemic tissue substrate modifies likelihood of LV contractile recovery; Aim 3 will test prognostic impact of infarction, hypoperfusion, and non-ischemic substrate after revasc, with focus on residual myocardial tissue properties as predictors of persis- tent LV dysfunction, impaired quality of life, and clinical events (HF readmission, mortality). Our team provides complementary expertise in key project relevant areas - translational CMR research, cardiac surgery, heart fail- ure, and clinical trials - and a track record of productive collaboration. Study findings are well-poised to transform the imaging paradigm through which viability is assessed and inform mechanism for persistent LV dysfunction, so as to improve therapeutic decision-making and clinical outcomes for millions of patients with iLVSD.