From the Department of Cardiology, Centre Medico Chirurgical Parly 2, Le Chesnay, France (M.H.); Departments of Cardiology (S.G.) and Radiology (A.R., J.F.P.), Centre Chirurgical Marie Lannelongue, Le Plessis Robinson, France; Department of Physiology, School of Medicine, Université Paris-Sud, Le Kremlin-Bicêtre, France (A.C.); and INSERM UMR 999, Centre Chirurgical Marie Lannelongue, Le Plessis-Robinson, France (A.C.).
Radiology. 2015 Mar;274(3):684-92. doi: 10.1148/radiol.14140861. Epub 2014 Nov 19.
To assess the feasibility of exercise perfusion computed tomography (CT) in patients suspected of having hemodynamically significant coronary stenosis.
This study had institutional review board approval, and all patients gave informed consent. Thirty-two consecutive patients (26 men [mean age, 63 years] and six women [mean age, 71 years]) with 55 coronary stenoses of at least 50% underwent coronary CT angiography (one stenosis in 13 patients, two stenoses in 15 patients, and three stenoses in four patients). CT myocardial perfusion imaging was performed within 1 minute after patients performed supine exercise on an ergometer secured to the CT table. The pressure-rate product was computed to assess level of exercise. The myocardial enhancement ratio between stenotic and normally perfused territories was determined for each stenosis. Fractional flow reserve less than 0.8, as measured during invasive coronary angiography, was the reference for defining significant stenoses. Receiver operating characteristic curves were constructed to determine the myocardial enhancement ratio cutoff value.
In the per-patient analysis, a myocardial enhancement ratio cutoff of 0.8 performed best for identifying functionally significant stenosis: Sensitivity was 95% (21 of 22 patients), specificity was 90% (nine of 10 patients), positive predictive value was 95% (21 of 22 patients), negative predictive value was 90% (nine of 10 patients), and accuracy was 94% (30 of 32 patients). Corresponding values in the per-stenosis analysis were 97% (29 of 30 stenoses), 96% (23 of 24 stenoses), 97% (29 of 30 stenoses), 96% (23 of 24 stenoses), and 96% (52 of 54 stenoses), respectively.
Exercise CT myocardial perfusion imaging is feasible and accurate for assessment of the functional significance of coronary stenosis.
评估在疑似存在血流动力学意义重大的冠状动脉狭窄的患者中进行运动灌注计算机断层扫描（CT）的可行性。
本研究获得了机构审查委员会的批准，所有患者均签署了知情同意书。连续 32 例患者（26 名男性[平均年龄 63 岁]和 6 名女性[平均年龄 71 岁]）接受了 55 处至少 50%狭窄的冠状动脉 CT 血管造影检查（13 例患者有 1 处狭窄，15 例患者有 2 处狭窄，4 例患者有 3 处狭窄）。在患者在固定于 CT 台的测力计上进行仰卧位运动后 1 分钟内进行 CT 心肌灌注成像。计算压力-速率乘积以评估运动水平。确定每个狭窄部位狭窄和正常灌注区域之间的心肌增强比。在有创冠状动脉造影中测量的小于 0.8 的分流量储备值是定义显著狭窄的参考标准。构建受试者工作特征曲线以确定心肌增强比的临界值。
在患者水平分析中，心肌增强比的截断值为 0.8 时，最适合识别功能意义重大的狭窄：敏感性为 95%（22 例患者中的 21 例），特异性为 90%（10 例患者中的 9 例），阳性预测值为 95%（22 例患者中的 21 例），阴性预测值为 90%（10 例患者中的 9 例），准确性为 94%（32 例患者中的 30 例）。在狭窄部位水平分析中，相应的值分别为 97%（30 处狭窄中的 29 处）、96%（24 处狭窄中的 23 处）、97%（30 处狭窄中的 29 处）、96%（24 处狭窄中的 23 处）和 96%（54 处狭窄中的 52 处）。
运动 CT 心肌灌注成像可用于评估冠状动脉狭窄的功能意义，且具有可行性和准确性。
