CARDIAC MRI PREDICTORS IN A "MADIT-II-LIKE" POPULATION

这个子项目是利用由NIH/NCRR资助的中心拨款提供的资源的许多研究子项目之一。子项目和调查员(PI)可能从另一个NIH来源获得了主要资金，因此可能会出现在其他CRISE条目中。列出的机构是针对中心的，而不一定是针对调查员的机构。多中心自动除颤器植入试验II(MADIT-II)显示，在无创测试的情况下，植入可植入的心脏复律除颤器(ICD)是有益的。然而，使用这一标准进行治疗所需的数量是之前要求ICD植入前进行侵入性测试的标准的两倍。我们希望找到非侵入性手段来确定谁将从ICD中受益。这项研究将检验这样一种假设，即心脏MRI的特征决定了有资格接受ICD植入但不会接受未来电击的患者亚组。西北纪念医院计划植入ICD的58名患者，符合MADIT-II标准(EF 30%，既往MI)。他们将在装置植入前获得可存活的心脏MRI图像，以及动态心电图、平均信号心电图、T波交替和心电图。然后对这些患者进行一年以上的随访，并记录第一次合适的ICD放电的时间。所有患者将根据存活MRI梗死区面积分为两组。然后，我们将对两组患者第一年首次除颤的时间进行Kaplan-Meier分析，并对其余测量变量进行多变量分析，以寻找其他可以预测休克的重要非侵入性指标，如t波交替。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The Multicenter Automatic Defibrillator Implantation Trial II (MADIT-II) has shown benefit for Implantible Cardioverter Defibrillator (ICD) implantation without invasive testing. However, the number needed to treat using this criterion is two-fold higher that the previous criteria that required invasive testing prior to ICD implantation. We would like to find non-invasive means for determining who would benefit from an ICD. This study will test the hypothesis that the characteristics on cardiac MRI determines the subgroup of patients that qualify for ICD implantation but will not receive future shocks. Fifty-eight patients who are scheduled for ICD implantation at Northwestern Memorial Hospital who meet MADIT-II criteria (EF 30%, prior MI). They will have viability cardiac MRI images acquired, as well as holter, signal averaged ECG, t-wave alternans, and ECGs prior to device implantation. These patients will then be followed over one year, and the time to the first appropriate ICD firing will be recorded. All patients will be segregated into two groups based on the viability MRI infarct surface area. We will then perform a Kaplan-Meier analysis of time to first defibrillation over the first year for both groups, as well as a multivariate analysis on the remaining measured variables to look for other significant non-invasive measures that can predict shock such as t-wave alternans.