ST段抬高型心肌梗死患者低剂量动态心肌灌注定量心肌血流量与高敏肌钙蛋白峰值水平及左心室功能的相关性

Correlation of low-dose dynamic CT myocardial perfusion imaging derived myocardial blood flow with peak troponin level and impaired left ventricle function in ST-elevated myocardial infarction patients

目的观察ST段抬高型心肌梗死(STEMI)患者低剂量动态心肌灌注定量心肌血流量(MBF)与高敏肌钙蛋白(hs-TnT)峰值水平及左心室功能受损程度的相关性。方法对35例发病1周内血管再通成功的STEMI患者行动态负荷CT动态心肌血流灌注(CT-MPI)检查,计算相关血流动力学参数,并收集hs-TnT数值及左心室射血分数(LVEF);对其中25例的相关血流动力学参数与hs-TnT水平及LVEF行相关性分析。结果动态CT-MPI平均辐射剂量为(3.30±1.12)mSv;梗死心肌区域MBF为(30.80±14.65)ml/(min·100 ml),低于参考区域的(72.80±10.70)ml/(min·100 ml)(P<0.001),心肌血容量(MBV)为(1.70±1.40)ml/100 ml低于参考区域的(4.10±2.00)ml/100 ml(P=0.02);MBF与hs-TnT峰值(r=-0.61,P=0.001)及LVEF值(r=0.46,P=0.02)显著相关,其他血流动力学参数与hs-TnT峰值及LVEF值均无明显相关。结论动态CT-MPI定量计算MBF值与hs-TnT峰值呈显著负相关,MBF值显著降低患者左心室功能亦减低。

Objective To investigate the correlation of low-dose dynamic computed tomography(CT) myocardial perfusion imaging(MPI) derived myocardial blood flow(MBF) with troponin level and left ventricle(LV) function in patients with ST-segment elevated myocardial infarction(STEMI). Methods Thirty-five STEMI patients underwent reperfusion treatment within 1 week of infarction and dynamic CT-MPI. Serial high-sensitivity troponin T(hs-TnT) levels and left ventricular ejection fraction(LVEF) were measured and recorded. Twenty-five patients were included for analysis. Various quantitative parameters derived from dynamic CT-MPI were analyzed to observe weather there were correlations of hs-TnT levels and LVEF on admission. Results The mean radiation dose for dynamic CT-MPI was(3.30±1.12)mSv. MBF in infarcted territories was(30.8± 14.65)ml/(min·100 ml), lower than that in reference territories([72.8±10.7]ml/[min·100 ml], P<0.001). The myocardial blood volume(MBV) in infarcted territories was(1.7±1.4)ml/100 ml, lower than that in reference territories([4.10±2.00]ml/100 ml, P=0.024). MBF showed the best correlation with the level of peak hs-TnT(r=-0.61, P=0.001), while the other parameters did not show significant correlation with hs-TnT levels. As for the association with LV function, only MBF was significantly correlated with LVEF at the time of admission(r=0.46, P=0.02). Conclusion MBF quantified with dynamic CT-MPI is significantly inversely correlated with the level of peak hs-TnT. In addition, STEMI patients with lower MBF tend to have impaired LV function.