Long-Term Outcome After Deferral of Revascularization in Patients With Intermediate Coronary Stenosis and Gray-Zone Fractional Flow Reserve

Abstract

Background:A strategy of deferred percutaneous coronary intervention for coronary stenosis with fractional flow reserve (FFR) 0.75–0.80, termed the gray zone, remains a matter of debate. The aim of this study was to assess the safety of deferring revascularization for patients with FFR 0.75–0.80 compared with those with FFR >0.80.Methods and Results:We assessed 3-year clinical outcome in 150 patients with angiographically intermediate stenosis who had revascularization deferred on the basis of FFR ≥0.75 (FFR 0.75–0.80, n=56; FFR >0.80, n=94). Target vessel failure (TVF), defined as a composite of cardiac death, target vessel-related myocardial infarction (MI), and ischemia-driven target vessel revascularization (TVR) was evaluated during follow-up. Cardiac death was observed in 1 patient with FFR 0.75–0.80. There was no target vessel-related MI in either group. The incidence of ischemia-driven TVR was higher in patients with FFR 0.75–0.80 than in those with FFR >0.80 (14% vs. 3%, P=0.020). TVF-free survival was significantly worse for the patients with FFR 0.75–0.80 than those with FFR >0.80 (hazard ratio, 5.2; 95% confidence intervals: 1.4–19.5; P=0.015).Conclusions:Patients with FFR 0.75–0.80 were at higher risk of TVF mainly due to TVR than those with FFR >0.80. (Circ J 2015; 79: 91–95)