Background: The primary reference criterion for evaluating coronary artery stenosis functional significance is fractional flow reserve (FFR). It helps the interventionist to define appropriate angiographic borderline coronary lesions that should or should not be treated with a stent. Objective: To evaluate the experience of the cardiology department, MUST University, on the use of FFR and its impact on patients with a borderline coronary lesion as regard revascularization decision-making. Patients and methods: A retrospective study were done on 86 patients with borderline lesions undergoing coronary angiograms for whom FFR was performed. Three experienced cardiac interventionists re-analyzed their coronary angiography and whether to delay or conduct revascularization with borderline stenotic lesions (40-70 %). A distinction was made between the findings of quantitative coronary angiography (QCA), visual and functional assessment of coronary stenosis severity. Result: Eighty-six patients (51 males and 35 females) with a mean age of 58.60 ± 9.20 were enrolled in the current study. FFR was < 0.80 in 26.74% (23/86) of the patients, and they had coronary angioplasty. Between quantitative evaluation of lesion diameter by FFR and visual measurement, the correlation was -0.645 (P < 0.001). Seven patients (8.139%) had FFR > 0.8 left main (LM) lesion and for the other vessels with severe coronary lesions, stenting was performed. Conclusion:  In patients having borderline coronary artery stenosis, FFR is an important tool for clinical decisions making about procedures of revascularization. FFR results in alteration in the coronary intervention judgment.