Internal Medicine Division, University Hospital, University of São Paulo Medical School, Av. Lineu Prestes 2565, CEP: 05508-000, Butanta, Sao Paulo, Brazil.
J Cardiovasc Comput Tomogr. 2012 Mar-Apr;6(2):121-6. doi: 10.1016/j.jcct.2011.12.006. Epub 2012 Jan 28.
Because of their similar visual appearance, differentiation of left ventricular thrombotic material and myocardial wall can be difficult in contrast-enhanced coronary computed tomography (CT) angiography.
We identified typical thrombi attenuation of left ventricular thrombi with the use of CT measurement.
Over a time period of 6 years, we retrospectively identified 31 patients who showed a left ventricular thrombus in CT angiography datasets. Patients underwent routine contrast cardiac CT to investigate coronary artery disease. CT attenuation of each thrombus was assessed in the 4-chamber view. CT densities were also determined in the ascending aorta, left ventricle, and myocardial wall both in the mid-septal and mid-lateral segments. The mean CT attenuation of thrombi and the difference between attenuation in thrombi, left ventricular cavity, and myocardial wall were determined. The ratio of attenuation values in thrombus versus aorta and myocardium versus aorta were also determined.
Mean (±SD) CT attenuation of all left ventricular thrombi in 31 patients was 43.2 ± 15.3 HU (range, 25-80 HU). Mean CT densities of septal and lateral myocardial wall were 102.9 ± 23.1 HU (range, 63-155 HU) and 99.3 ± 28.7 HU (range, 72-191 HU), respectively, and were thus significantly higher than the CT attenuation of thrombi (P < 0.001). A threshold of 65 HU yielded a sensitivity, specificity, and positive and negative predictive values of 94%, 97%, 94%, and 97%, respectively, to differentiate thrombus from the myocardial wall. The mean ratio between CT attenuation of thrombus and CT attenuation within the ascending aorta was 0.11 ± 0.05 (range, 0.04-0.23), which was significantly lower compared with the mean ratio between CT attenuation of the myocardial wall and the CT attenuation within the ascending aorta.
CT attenuation within left ventricular thrombi was significantly lower than myocardial attenuation in CT angiography datasets. Assessment of CT attenuation may contribute to the differentiation of thrombi.
由于左心室血栓的外观相似，在对比增强冠状动脉计算机断层扫描（CT）血管造影中，区分左心室血栓的形成物质和心肌壁可能具有一定难度。
我们使用 CT 测量来确定左心室血栓的典型血栓衰减。
在 6 年的时间内，我们回顾性地确定了 31 例 CT 血管造影数据集显示左心室血栓的患者。患者接受常规对比增强心脏 CT 检查以调查冠状动脉疾病。在四腔心视图中评估每个血栓的 CT 衰减。还在升主动脉、左心室以及中隔和中侧壁的心肌段分别测量左心室血栓、左心室腔和心肌壁的 CT 密度。确定血栓的平均 CT 衰减以及血栓与左心室腔和心肌壁之间的衰减差异。还确定了衰减值在血栓与主动脉和心肌与主动脉之间的比值。
31 例患者所有左心室血栓的平均（±标准差）CT 衰减值为 43.2 ± 15.3 HU（范围，25-80 HU）。中隔和外侧心肌壁的平均 CT 密度分别为 102.9 ± 23.1 HU（范围，63-155 HU）和 99.3 ± 28.7 HU（范围，72-191 HU），均显著高于血栓的 CT 衰减值（P < 0.001）。阈值为 65 HU 时，区分血栓与心肌壁的敏感性、特异性、阳性预测值和阴性预测值分别为 94%、97%、94%和 97%。血栓与升主动脉内 CT 衰减值的平均比值为 0.11 ± 0.05（范围，0.04-0.23），明显低于心肌壁与升主动脉内 CT 衰减值的平均比值。
左心室血栓内的 CT 衰减明显低于 CT 血管造影数据集的心肌衰减。CT 衰减评估可能有助于区分血栓。
