冠状动脉造影指标对中度狭窄病变功能意义的判断价值

Coronary angiographic criteria for assessment of functional significance in intermediate coronary artery stenosis

目的 评估冠状动脉造影 (coronaryarteryangiography ,CAG)测定的指标对冠状动脉中度狭窄病变功能意义的判断价值。方法 46支CAG显示中度狭窄 (直径狭窄率 40 %～ 60 % )的冠状动脉 ,压力导丝测定心肌血流储备分数 (myo cardialfractionalflowreserve ,FFRmyo) ;定量CAG测量直径狭窄率和最小管腔直径。以FFRmyo<0 75为界限值 ,采用受试者工作特征曲线 (receiveroperatingcharacteristic ,ROC)选择CAG测量的每个指标的截断点。结果 46支血管病变的直径狭窄率(4 9 3 4± 11 45 ) % ,FFRmyo为 (0 83± 0 15 ) ,显著低于正常组 (FFRmyo为 0 97± 0 0 2 )。 14处 (3 0 % )病变低于界限值 (FFRmyo<0 75 )。CAG直径狭窄率与FFRmyo呈负相关 (r =-0 5 9,P <0 0 1)。以FFRmyo<0 75为界限值 ,根据ROC分析 ,直径狭窄率≥ 5 0 %为截断点 ,灵敏度 =63 64 % ,特异性 =84 0 0 %。最小管腔直径与FFRmyo呈正相关 (r =0 62 ,P <0 0 1)。以最小管腔直径≤ 1 5mm为截断点 ,灵敏度 =68 75 % ,特异性 =89 66%。以直径狭窄率≥ 5 0 %和最小腔直径≤ 1 5mm联合计算 ,灵敏度 =88 64 %。结论 CAG直径狭窄率≥ 5 0 %、最小管腔直径≤ 1 5mm ,能较准确地判断中度狭窄病变的FFRmyo。

Objective To evaluate the roles of coronary angiography (CAG) in the assessment of functional significance in intermediate coronary artery lesions. Methods In 46 lesions of intermediate severity (e.g., 40% to 60% diameter stenosis), myocardial fractional flow reserve (FFR myo , index of functional significance) was assessed by pressure wire and minimal lumen diameter (MLD) and percent diameter stenosis at the lesion site were quantitatively assessed by CAG. Receiver operating characteristic (ROC) curve analysis was performed to establish the best cut-off values of IVUS indexes (i.e., MLD and percent diameter stenosis) that were most predictive of FFR myo <0.75. Results FFR myo in 46 lesions of angiographic intermediate stenosis [(49.34±11.45)%] was significantly lower than that in angiographic normal artery [(0.83±0.15) vs (0.97±0.02), P<0.01]. Fourteen lesions (30%) were functionally critical (e.g., FFR myo <0.75). Regression analysis revealed that percent diameter stenosis was negatively correlated with FFR myo (r=-0.59, P<0.01). MLD showed a significant positive relation with FFR myo (r=0.62, P<0.01). By ROC analysis, we identified a CAG diameter stenosis ≥50% (sensitivity: 63.64%; specificity: 84.00%) and an MLD≤1.5 mm (sensitivity: 68.75%; specificity: 89.66%) to be the best cut-off values to fit with FFR myo <0.75. The combined evaluation of both percent diameter stenosis and MLD made the CAG examination more sensitive (88.64%). Conclusion CAG diameter stenosis ≥50% and minimal lumen diameter ≤1.5 mm can be helpful to identify the functional significance in intermediate coronary stenosis.