RESUMEN
【Objective】 To develop a simple and practical diagnostic protocol to optimize patient screening for fractional flow reserve（FFR）. 【Methods】 Consecutive patients who underwent both invasive coronary angiography and lesion-specific FFR measurement from July 2013 to August 2018 were retrospectively screened， resulting in a total of 372 patients（390 lesions） for inclusion. Visual estimation（VE） of stenosis was obtained from experts while percent diameter stenosis（DS%）， percent area stenosis（AS%）， lesion length（LL）， minimal lumen diameter（MLD）， and the ratio of LL to the fourth power of MLD（LL/MLD4） were recorded by quantitative software. An FFR value of ≤0.80 was considered to indicate the physiological significance of stenosis. 【Results】 The median age（25th-75th percentiles） of the included patients was 66 years（59-74 years） and positive FFR results were identified in 77 lesions（19.7%）. The area under the receiver-operating characteristic curve was revealed as 0.711（95% CI 0.663-0.755） for VE， significantly greater than DS%（0.605）， AS%（0.608）， and LL（0.612； P<0.05 for all）， but without significant difference from that of MLD（0.667） and LL/MLD4（0.702）. The combination of VE with LL/MLD4 yielded a high sensitivity of 89.6%（95% confidence interval ［CI］， 80.6-95.4） and a negative predictive value of 94.4%（95% CI， 89.2-97.5）. 【Conclusion】 Overall， the combination of VE with LL/MLD4 can effectively identify those low-risk lesions for ischemia to avoid unnecessary FFR measurement， thus optimizing the use of pressure wire as well as reducing total medical expenditure and potential complications.