Myocardial Viability and Remodeling in the OAT

正在进行的由NHLBI资助的闭塞动脉试验（OAT）旨在测试开放动脉的假设， MI后3-28天的梗死相关动脉（伊拉）闭塞将降低以下复合终点： 死亡率、复发性MI和NYHA IV级心力衰竭。审裁处目前已 在24个国家的240个中心随机分配了大约1100名患者。在提议的机制中， 解释晚期血运重建、LV功能恢复和LV重塑减弱的益处， 恢复血流至存活心肌是最合理的。我们建议就审裁处进行辅助研究 评估存活心肌对心肌梗死后左室重构的影响，并探讨心肌梗死后左室重构与存活心肌的关系。 梗死区存活率、LV重构和对OAT干预的反应之间， 伊拉的PCI。为此，我们建议入组200名患者，参加OAT的生存能力和重塑研究。 辅助研究（OAT-NUC）。本研究的主要具体目的是：1）检验患者 在梗塞区中存活的患者将表现出较少的进行性重塑 与表现出主要梗死的患者相比，以及2）为了检验保留心肌梗死的假设， 存活率将改变MI后患者随机化至晚期血运重建的治疗效果， AMI后3-28天伊拉闭塞。所有患者将接受静息门控Tc-99 m sestamibi SPECT成像 在基线时，1年后再次。梗死区内的基线活力参数，以及 LV容积变化和功能指标将由心脏成像核心中心进行集中评估 塔夫茨新英格兰医学中心的实验室，一个拥有丰富心脏分析经验的团队 多中心临床试验中的影像学数据。解决假设的主要研究终点将是连续的 根据定义的梗死范围内存活力的保存程度，左心室舒张末期容积的变化 区样本量计算基于同一组从相似数量的 在类似数量的临床研究中心研究的患者。因此，样本量预测是稳健的， 适合目前的审判，调查小组有经验进行拟议的 以高质量学习。OAT-NUC是OAT的唯一可行性辅助研究，因此满足了关键需求 评估OAT结果的潜在机制。

The ongoing NHLBI-funded Occluded Artery Trial (OAT) is designed to test the hypothesis that opening an occluded infarct related artery (IRA) 3-28 days following an MI will reduce the composite endpoint of mortality, recurrent MI, and NYHA class IV heart failure over three-year follow-up. OAT has currently randomized approximately 1100 patients in 240 centers in 24 countries. Among the mechanisms proposed to explain benefit of late revascularization, recovery of LV function and attenuation of LV remodeling due to restoration of blood flow to viable myocardium is the most plausible. We propose an ancillary study of OAT to assess the effect of myocardial viability on LV remodeling post-MI, and to explore the relationships between retained viability of the infarct zone, LV remodeling, and the response to the OAT intervention, late PCI of the IRA. To this end, we propose to enroll 200 patients in the Viability and Remodeling in OAT Ancillary Study (OAT-NUC). The primary specific aims of this study are 1) to test the hypothesis that patients who demonstrate preservation of viability within the infarct zone will evidence less progressive remodeling compared to patients exhibiting predominant infarct, and 2) to test the hypothesis that preservation of viability will modify the treatment effect of randomization to late revascularization of post-MI patients with an occluded IRA 3-28 days after an AMI. All patients will have resting gated Tc-99m sestamibi SPECT imaging at baseline, and again 1 year later. Parameters of baseline viability within the infarct zone, and serial measures of LV volume change and function will be centrally assessed by the Cardiac Imaging Core Laboratory at Tufts-New England Medical Center, a group with substantial experience analyzing cardiac imaging data in multicenter clinical trials. The major study endpoint to address the hypotheses will be serial change in LV end-diastolic volume, based on the degree of preservation of viability within the defined infarct zone. Sample size calculations are based on data evaluated by the same group from a similar number of patients studied at a similar number of clinical sites. Hence, sample size projections are robust and appropriate for the current trial, and the investigative group has the experience to carry out the proposed study with high quality. OAT-NUC is the only viability ancillary study of OAT, and thus serves a critical need in assessing potential mechanisms of the findings in OAT.