基于CTA数据有限元模拟测量FFR值与临床验证

Calculate FFR Value Based on CTA Data with Finite Element Simulation and Clinical Verification

目的:基于CTA数据,利用SimVascular软件计算出血流储备分数(FFR)值,并进行临床验证。方法:基于CTA数据1例(血压118/78mmHg)构建CA三维几何模型,计算机辅助设计(CAD)技术使管腔变窄,SimVascular软件分别计算CA管壁压力及其不同狭窄程度的FFR值。其结果与临床压力导丝测量FFR、冠状动脉(CA)狭窄分级结果比较。结果:计算获得主动脉平均动脉压约91.893mmHg,血压118.39/72.56mmHg。计算出管腔狭窄率30%、40%、50%、60%、70%、75%、80%、90%对应的FFR值分别为0.976、0.968、0.951、0.938、0.814、0.724、0.716、0.167。临床常用冠脉CTA及DSA分度75%狭窄预测值基本相符。其中1例左前降支狭窄病例,压力导丝测得狭窄远端FFR值约0.66,而数值模拟测得FFR值0.668。结论:利用SimVascular软件可以模拟CA血流动力学状态,并计算出其管腔不同狭窄程度的FFR值,其结果与临床导管导丝直接测量FFR值、CA狭窄分级预测缺血情况基本一致。

Objective： Calculate the value of fractional flow reserve （FFR） based on CTA data using SimVascular software, and have the clinical verification. Methods： Based on the coronary CTA data, the 3D geometric model of CA was established and the lumen of CA was narrowed with the CAD technique. Their normal blood pressure and the FFR of CA in different stenosis were calculated on the SimVascular software, and the results were compared with clinical data. Results： The mean arterial pressure of the aorta was 91.893mmHg, the blood pressure was 118.39/72.56 mmHg calculated on the SimVascular. Their FFR in the lumen stenosis of 30%, 40%, 50%, 60%, 70%, 75%, 80%, 90%were0.976, 0.968, 0.951, 0.938, 0.814, 0.724, 0.716, 0.I67, which match up with the severe stenosis in CTA and DSA classification used in clinic. The FFP, value of the distal end of the stenosis was about 0.66 measured of pressure wire, and the FFR-CT value was 0.668 calculated by SimVascular. Conclusion： Hemodynamic state of CA can be described on the different stenosis with Simvascular software, and their FFR value can be calculated. They are consistent with the direct measurements and prediction from CA stenosis in clinic.