Hoffmann Rainer, Stempel Katharina, Kühl Harald, Balzer Jan, Krämer Niels, Krombach Gabriele, Kelm Malte, Becker Michael
Department of Cardiology, University Hospital RWTH Aachen, Germany.
Coron Artery Dis. 2009 Jan;20(1):21-6. doi: 10.1097/MCA.0b013e32831040a6.
Myocardial deformation imaging and contrast-enhanced cardiac magnetic resonance imaging (ceMRI) have been used to define myocardial viability in ischemic left ventricular dysfunction. This study evaluated the incremental predictive value of an integrated analysis of function and tissue structure for functional improvement after revascularization therapy.
In 59 patients with ischemic left ventricular dysfunction, myocardial viability was defined by pixel-tracking-derived myocardial deformation imaging and ceMRI to predict recovery of function at 9+/-2 months follow-up after revascularization. For each left ventricular segment in a 16-segment model, peak systolic radial strain was determined from parasternal two-dimensional echocardiographic views using an automatic frame-by-frame tracking system of natural acoustic echocardiographic markers, and extent of hyperenhancement using ceMRI. Five categories were generated for each parameter, allowing subsequent combination. The predictive power for segmental improvement in function was determined for each of the modalities as well as the combination of both.
From 512 dysfunctional segments at baseline, 251 segments (49%) demonstrated functional recovery. The accuracy to predict functional recovery was area under curve (AUC)=0.846 for peak systolic radial strain and AUC=0.834 for extent of hyperenhancement. A combination of both parameters improved the predictive accuracy compared with hyperenhancement alone, AUC=0.861, P value of less than 0.001. In sequential Cox models, the predictive power for segmental functional recovery of extent of hyperenhancement alone (chi model 171.0, P<0.001), or peak systolic radial strain alone (chi model 205.9, P<0.001), was strengthened by a combination of both parameters (chi model 248.5, P<0.001). The advantage of image integration was particularly strong in those segments with intermediate degree of late enhancement (DeltaAUC=0.065, P<0.001).
Integration of advanced information on myocardial function using deformation imaging and findings on myocardial tissue structure increases the accuracy to identify reversible myocardial dysfunction.
心肌形变成像和对比增强心脏磁共振成像（ceMRI）已被用于定义缺血性左心室功能障碍中的心肌存活情况。本研究评估了功能与组织结构综合分析对血运重建治疗后功能改善的增量预测价值。
在59例缺血性左心室功能障碍患者中，通过像素追踪衍生的心肌形变成像和ceMRI定义心肌存活情况，以预测血运重建后9±2个月随访时的功能恢复情况。在16节段模型中的每个左心室节段，使用自然声学超声心动图标记的自动逐帧跟踪系统，从胸骨旁二维超声心动图视图确定收缩期峰值径向应变，并使用ceMRI确定强化范围。为每个参数生成五类，以便后续组合。确定每种模态以及两者组合对节段性功能改善的预测能力。
在基线时的512个功能障碍节段中，251个节段（49%）显示功能恢复。预测功能恢复的准确性，收缩期峰值径向应变的曲线下面积（AUC）=0.846，强化范围的AUC=0.834。与单独的强化范围相比，两个参数的组合提高了预测准确性，AUC=0.861，P值小于0.001。在序贯Cox模型中，单独强化范围（卡方模型171.0，P<0.001）或单独收缩期峰值径向应变（卡方模型205.9，P<0.001）对节段性功能恢复的预测能力，通过两个参数的组合得到加强（卡方模型248.5，P<0.001）。图像整合的优势在晚期强化程度中等的节段中尤为明显（ΔAUC=0.065，P<0.001）。
使用形变成像的心肌功能高级信息与心肌组织结构的发现相结合，可提高识别可逆性心肌功能障碍的准确性。
