From the Departments of Cardiology (W.J.S., I.D., M.T.R., K.M.M., N.v.R., P.K.), Radiology and Nuclear Medicine (P.G.R., A.A.L, H.J.H., M.C.H.), Department of Epidemiology and Biostatistics (M.W.H.), VU University Medical Center, Amsterdam, The Netherlands; Turku PET Centre, Turku University Hospital and University of Turku, Turku, Finland (V.U., A.S., S.A.K, M.P., J.K.); and Department of Nuclear Medicine and PET, Institution of Radiology, Oncology and Radiation Science, Uppsala University, Uppsala, Sweden (T.K., J.S.).
Circ Cardiovasc Imaging. 2015 Jan;8(1). doi: 10.1161/CIRCIMAGING.114.002400.
Quantitative myocardial perfusion imaging is increasingly used for the diagnosis of coronary artery disease. Quantitative perfusion imaging allows to noninvasively calculate fractional flow reserve (FFR). This so-called relative flow reserve (RFR) is defined as the ratio of hyperemic myocardial blood flow (MBF) in a stenotic area to hyperemic MBF in a normal perfused area. The aim of this study was to assess the value of RFR in the detection of significant coronary artery disease.
From a clinical population of patients with suspected coronary artery disease who underwent oxygen-15-labeled water cardiac positron emission tomography and invasive coronary angiography, 92 patients with single- or 2-vessel disease were included. Intermediate lesions (diameter stenosis, 30%-90%; n=75) were interrogated by FFR. Thirty-eight (41%) vessels were deemed hemodynamically significant (>90% stenosis or FFR≤0.80). Hyperemic MBF, coronary flow reserve, and RFR were lower for vessels with a hemodynamically significant lesion (2.01±0.78 versus 2.90±1.16 mL·min(-1)·g(-1); P<0.001, 2.27±1.03 versus 3.10±1.29; P<0.001, and 0.67±0.23 versus 0.93±0.15; P<0.001, respectively). The correlation between RFR and FFR was moderate (r=0.54; P<0.01). Receiver operator characteristic curve analysis showed an area under the curve of 0.82 for RFR, which was not significantly higher compared with that for hyperemic MBF and coronary flow reserve (0.76; P=0.32 and 0.72; P=0.08, respectively).
Noninvasive estimation of FFR by quantitative perfusion positron emission tomography by calculating RFR is feasible, yet only a trend toward a slight improvement of diagnostic accuracy compared with hyperemic MBF assessment was determined.
定量心肌灌注成像是诊断冠状动脉疾病的常用方法。定量灌注成像可无创计算血流储备分数（FFR）。这种所谓的相对血流储备（RFR）定义为狭窄区域的充血性心肌血流（MBF）与正常灌注区域的充血性 MBF 的比值。本研究旨在评估 RFR 在检测显著冠状动脉疾病中的价值。
从疑似冠状动脉疾病的临床患者人群中，接受 15O-标记水心脏正电子发射断层扫描和有创冠状动脉造影检查，纳入 92 例单或双血管疾病患者。通过 FFR 检查中间病变（直径狭窄 30%-90%；n=75）。38 支（41%）血管被认为存在血流动力学意义上的狭窄（>90%狭窄或 FFR≤0.80）。存在血流动力学意义狭窄的血管的充血性 MBF、冠状动脉血流储备和 RFR 较低（2.01±0.78 与 2.90±1.16 mL·min(-1)·g(-1)；P<0.001，2.27±1.03 与 3.10±1.29；P<0.001，0.67±0.23 与 0.93±0.15；P<0.001，分别）。RFR 与 FFR 之间的相关性为中度（r=0.54；P<0.01）。接受者操作特征曲线分析显示 RFR 的曲线下面积为 0.82，与充血性 MBF 和冠状动脉血流储备的曲线下面积（0.76；P=0.32 和 0.72；P=0.08，分别）相比，无显著差异。
通过计算 RFR 对定量灌注正电子发射断层扫描进行无创性 FFR 估计是可行的，但与充血性 MBF 评估相比，仅确定诊断准确性略有提高的趋势。
