Weinsaft Jonathan W, Kim Jiwon, Medicherla Chaitanya B, Ma Claudia L, Codella Noel C F, Kukar Nina, Alaref Subhi, Kim Raymond J, Devereux Richard B
Greenberg Cardiology Division, Department of Medicine, Weill Cornell Medical College, New York, New York; Department of Radiology, Weill Cornell Medical College, New York, New York.
Greenberg Cardiology Division, Department of Medicine, Weill Cornell Medical College, New York, New York; Department of Radiology, Weill Cornell Medical College, New York, New York.
JACC Cardiovasc Imaging. 2016 May;9(5):505-15. doi: 10.1016/j.jcmg.2015.06.017. Epub 2015 Oct 14.
The goal of this study was to determine the prevalence of post-myocardial infarction (MI) left ventricular (LV) thrombus in the current era and to develop an effective algorithm (predicated on echocardiography [echo]) to discern patients warranting further testing for thrombus via delayed enhancement (DE) cardiac magnetic resonance (CMR).
LV thrombus affects post-MI management. DE-CMR provides thrombus tissue characterization and is a well-validated but an impractical screening modality for all patients after an MI.
A same-day echo and CMR were performed according to a tailored protocol, which entailed uniform echo contrast (irrespective of image quality) and dedicated DE-CMR for thrombus tissue characterization.
A total of 201 patients were studied; 8% had thrombus according to DE-CMR. All thrombi were apically located; 94% of thrombi occurred in the context of a left anterior descending (LAD) infarct-related artery. Although patients with thrombus had more prolonged chest pain and larger MI (p ≤ 0.01), only 18% had aneurysm on echo (cine-CMR 24%). Noncontrast (35%) and contrast (64%) echo yielded limited sensitivity for thrombus on DE-CMR. Thrombus was associated with stepwise increments in basal → apical contractile dysfunction on echo and quantitative cine-CMR; the echo-measured apical wall motion score was higher among patients with thrombus (p < 0.001) and paralleled cine-CMR decrements in apical ejection fraction and peak ejection rates (both p < 0.005). Thrombus-associated decrements in apical contractile dysfunction were significant even among patients with LAD infarction (p < 0.05). The echo-based apical wall motion score improved overall performance (area under the curve 0.89 ± 0.44) for thrombus compared with ejection fraction (area under the curve 0.80 ± 0.61; p = 0.01). Apical wall motion partitions would have enabled all patients with LV thrombus to be appropriately referred for DE-CMR testing (100% sensitivity and negative predictive value), while avoiding further testing in more than one-half (56% to 63%) of patients.
LV thrombus remains common, especially after LAD MI, and can occur even in the absence of aneurysm. Although DE-CMR yielded improved overall thrombus detection, apical wall motion on a noncontrast echocardiogram can be an effective stratification tool to identify patients in whom DE-CMR thrombus assessment is most warranted. (Diagnostic Utility of Contrast Echocardiography for Detection of LV Thrombi Post ST Elevation Myocardial Infarction; NCT00539045).
本研究的目的是确定当前时代心肌梗死后（MI）左心室（LV）血栓的患病率，并开发一种有效的算法（基于超声心动图[echo]），以识别需要通过延迟增强（DE）心脏磁共振（CMR）进一步检测血栓的患者。
LV血栓影响MI后的管理。DE-CMR可提供血栓组织特征，是一种经过充分验证但对所有MI后患者不实用的筛查方式。
根据定制方案进行同日echo和CMR检查，该方案要求使用统一的echo造影剂（无论图像质量如何），并进行专门的DE-CMR以进行血栓组织特征分析。
共研究了201例患者；根据DE-CMR，8%的患者有血栓。所有血栓均位于心尖；94%的血栓发生在左前降支（LAD）梗死相关动脉的情况下。虽然有血栓的患者胸痛持续时间更长且MI更大（p≤0.01），但只有18%的患者在echo上有室壁瘤（cine-CMR为24%）。非增强（35%）和增强（64%）echo对DE-CMR上血栓的敏感性有限。血栓与echo和定量cine-CMR上从基底到心尖收缩功能障碍的逐步增加相关；血栓患者的echo测量的心尖壁运动评分更高（p<0.001），与cine-CMR上心尖射血分数和峰值射血率的降低平行（均p<0.005）。即使在LAD梗死患者中，血栓相关的心尖收缩功能障碍的降低也很显著（p<0.05）。与射血分数（曲线下面积0.80±0.61；p=0.01）相比，基于echo的心尖壁运动评分改善了血栓的总体表现（曲线下面积0.89±0.44）。心尖壁运动分区可使所有LV血栓患者被适当地转诊进行DE-CMR检测（100%的敏感性和阴性预测值），同时避免超过一半（56%至63%）的患者进行进一步检测。
LV血栓仍然常见，尤其是在LAD MI后，甚至在没有室壁瘤的情况下也可能发生。虽然DE-CMR提高了总体血栓检测率，但非增强超声心动图上的心尖壁运动可以是一种有效的分层工具，用于识别最需要进行DE-CMR血栓评估的患者。（对比超声心动图对ST段抬高型心肌梗死后LV血栓检测的诊断效用；NCT00539045）
