CT-FFR is an important noninvasive examination to evaluate the function of coronary artery disease. It can help clinicians make clinical decisions and reduce patients' invasive coronary angiography (ICA). The image quality of coronary CT angiography (CCTA) is the basis of CT-FFR measurement. Because metal stents seriously interfere with the imaging of CCTA, it is very difficult to measure the CT-FFR value of lesions in stents. However, a large number of patients need imaging follow-up evaluation after stenting. In the previous research, the investigators creatively invented a new algorithm ISR-Net and conducted a retrospective analysis. It is preliminarily proved that the algorithm can more accurately display the stenosis lesions in the stent than the previous imaging software, making it possible to calculate the CT-FFR of the lesions in the stent. At present, the algorithm has applied for a national invention patent. In order to transform to clinical application, further clinical verification is needed. This study will evaluate the accuracy of ISR-Net algorithm in assessing the function of coronary stent stenosis by carrying out prospective clinical trials and taking the blood flow reserve fraction (FFR) measured by pressure wire as the gold standard. At the same time, the standard process of CT-FFR measurement of in stent lesions was established. The research results are of great significance to solve the bottleneck problem of CT-FFR and expand its application scope.
CT-FFR(CT-derived flow reserve fraction) usually could not been measured accurately for in-stent lesions due to the serious interference with the metal structs. ISR-Net is a new algorithm in assessing the flow of coronary in-stent stenosis. We compare the CT-FFR value of in-stent lesions with the invasive FFR measured by pressure wire to evaluate the accuracy of ISR-Net algorithm. The research results are of great significance to solve the bottleneck problem of CT-FFR and expand its application scope.