Matsumura-Nakano Y, Kawaji T, Shiomi H, et al. - In order to define the optimal cutoff value of fractional flow reserve (FFR) derived from coronary computed tomography angiography (FFR_CT), researchers analyzed 93 patients with 139 vessels, with computed tomography angiography-suggested suspected coronary artery disease. These patients had undergone invasive FFR. Based on different FFR_CT cutoff values and FFR_CT ranges, the diagnostic performance of FFR_CT was assessed. The reference standard was invasive FFR ≤ 0.80. Based on the findings, considering referral to invasive coronary angiography individually in the range of FFR_CT 0.71 to 0.80 was recommended. In FFR_CT ≤ 0.70 and > 0.80, dichotomous decision could be made. To define optimal FFR_CT-based diagnostic algorithm, the need for prospective investigations assessing clinical outcomes was highlighted.