Context: The decision to perform an intervention on a narrowed coronary artery depends on the ischemia caused by the stenosis. The indication for intervention usually applies to cases with ≥70% stenosis of vascular diameter because of the risk of myocardial ischemia. Aims: To define the efficacy of fractional flow reserve (FFR) measurement in the evaluation of coronary artery stenosis. Methods: This prospective study was conducted on patients with intermediate coronary artery stenosis who underwent quantitative coronary angiography after coronary computed tomography angiography. Results: The study population consisted of 46 men and 26 women with a mean age of 66.0 ± 12.9 years. FFR was significantly correlated with the grade of angina pectoris (r = – 0.387; p<0.01) and showed a negative correlation with percentage diameter stenosis (r = – 0.241, p<0.05) and a positive correlation with the minimal lumen diameter (MLD; r = 0.377, p<0.05). The cut-off value to predict positive FFR was >55.62% diameter stenosis and MLD ≤ 1.08 mm. FFR ≤ 0.80 indicating intervention and FFR > 0.80 indicating medical therapy were observed in 56.9% and 43.1% of the cases, respectively. No major cardiac complications occurred during 12 months of follow-up in both groups. Conclusions: FFR measurements for intermediate stenosis of the coronary artery should be used to evaluate the possibility of myocardial ischaemia. If FFR is not available, a cut-off point of >55.62% diameter stenosis or MLD ≤ 1.08 mm can be used to predict the FFR results.

Background: Indication for treatment of intermediate coronary artery lesions is wavering. Worldwide studies showed the role of FFR in guiding the treatment for these cases. Objective: To study the outcomes of FFR-guided PCI in intermediate coronary artery lesions. Method: Cohort study with comparative analysis of 12-month MACE between two groups: Medical treatment with FFR > 0.8 and PCI with FFR ≤ 0.8. Results: 40 stenosis lesions with FFR ≤ 0.8 (57.14%) was treated by PCI and 30 stenosis lesions with FFR > 0.8 treated by medical therapy. The percentage stenotic diameter cut-off was >55.62% on QCA with Sp 60% and Se 75%. There was no significant difference in MACE between two groups after 12-month follow-up. Conclusions: FFR has important role in guiding treatment for intermediate coronary artery lesions. Key words: ffR-guided, coronary arery