Cardiac MR PET CT Program, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA.
JACC Cardiovasc Imaging. 2013 Jan;6(1):72-82. doi: 10.1016/j.jcmg.2012.08.014.
The goal of this study was to determine the ability of a single, resting high-sensitivity troponin T (hsTnT) measurement to predict abnormal myocardial perfusion imaging (MPI) in patients presenting with acute chest pain to the emergency department (ED).
HsTnT assays precisely detect very low levels of troponin T, which may be a surrogate for the presence and extent of myocardial ischemia.
We included all patients from the ROMICAT I (Rule Out Myocardial Infarction Using Computer Assisted Tomography) trial, an observational cohort study, who underwent both single-photon emission computed tomography (SPECT)-MPI stress testing and 64-slice computed tomography angiography (CTA) and in whom hsTnT measurements were available. We assessed the discriminatory value of hsTnT for abnormal SPECT-MPI and the association of reversible myocardial ischemia by SPECT-MPI and the extent of coronary atherosclerosis by CTA to hsTnT levels.
Of the 138 patients (mean age 54 ± 11 years, 46% male), 19 (13.7%) had abnormal SPECT-MPI. Median hsTnT levels were significantly different between patients with normal and abnormal SPECT-MPI (9.41 pg/ml [interquartile range (IQR): 5.73 to 19.20 pg/ml] vs. 4.89 pg/ml [IQR: 2.34 to 7.68 pg/ml], p = 0.001). Sensitivity of 80% and 90% to detect abnormal SPECT-MPI was reached at hsTnT levels as low as 5.73 and 4.26 pg/ml, respectively. Corresponding specificity was 62% and 46%, and negative predictive value was 96% and 96%, respectively. HsTnT levels had good discriminatory ability for prediction of abnormal SPECT-MPI (area under the curve: 0.739, 95% confidence interval: 0.609 to 0.868). Both reversible myocardial ischemia and the extent of coronary atherosclerosis (combined model r(2) = 0.19 with partial of r(2) = 0.12 and r(2) = 0.05, respectively) independently and incrementally predicted the measured hsTnT levels.
In patients with acute chest pain, myocardial perfusion abnormalities and coronary artery disease are predicted by resting hsTnT levels. Prospective evaluations are warranted to confirm whether resting hsTnT could serve as a powerful triage tool in chest pain patients in the ED before diagnostic testing and improve the effectiveness of patient management.
本研究旨在确定单次静息高敏肌钙蛋白 T（hsTnT）测量值预测因急性胸痛就诊于急诊科（ED）患者异常心肌灌注成像（MPI）的能力。
hsTnT 检测法可精确检测到极低水平的肌钙蛋白 T，后者可能是心肌缺血存在和严重程度的替代指标。
我们纳入了来自 ROMICAT I（使用计算机辅助断层扫描排除心肌梗死）试验的所有患者，这是一项观察性队列研究，这些患者均同时接受单光子发射计算机断层扫描（SPECT）-MPI 应激试验和 64 层 CT 血管造影（CTA）检查，并且可获得 hsTnT 测量值。我们评估了 hsTnT 对 SPECT-MPI 异常的诊断价值，以及 SPECT-MPI 显示的可逆性心肌缺血和 CTA 显示的冠状动脉粥样硬化程度与 hsTnT 水平之间的相关性。
在 138 例患者（平均年龄 54±11 岁，46%为男性）中，有 19 例（13.7%）患者的 SPECT-MPI 异常。SPECT-MPI 正常和异常患者的 hsTnT 中位数水平差异具有统计学意义（9.41pg/ml [四分位距（IQR）：5.73 至 19.20pg/ml] vs. 4.89pg/ml [IQR：2.34 至 7.68pg/ml]，p=0.001）。hsTnT 水平分别低至 5.73pg/ml 和 4.26pg/ml 时，其对 SPECT-MPI 异常的检测敏感性分别达到 80%和 90%。相应的特异性分别为 62%和 46%，阴性预测值分别为 96%和 96%。hsTnT 水平对 SPECT-MPI 异常的预测具有良好的判别能力（曲线下面积：0.739，95%置信区间：0.609 至 0.868）。可逆性心肌缺血和冠状动脉粥样硬化程度（联合模型 r²=0.19，偏 r²=0.12，r²=0.05）均独立且呈增量式地预测了测量的 hsTnT 水平。
在因急性胸痛就诊的患者中，静息 hsTnT 水平可预测心肌灌注异常和冠状动脉疾病。需要前瞻性评估来确认静息 hsTnT 是否可作为 ED 胸痛患者在诊断性检查前的强大分诊工具，以改善患者管理的效果。
