Actual FFR value predicts natural history of stenoses in patients with stable coronary disease. A FAME 2 trial subanalysis

Abstract

Purpose: In the FAME 2 trial, patients (pts) with stable coronary disease treated with medical therapy (MT) presented an increased need for urgent revascularization in the presence of stenoses with FFR<0.80 compared to pts with stenoses with FFR>0.80. We investigated the relationship between the actual FFR values and target lesion failure (TLF). Methods: This sub-analysis of the FAME 2 trial included only patients who did not receive PCI, but with stenosis in major epicardial coronaries: registry pts (n=166) and pts randomized to MT (n=441). TLF was defined as the composite of cardiovascular death, myocardial infarction, and ischemia-driven target lesion revascularization (both urgent and non-urgent). The relationship between FFR and 1-year TLF was assessed as continuous function. Cox proportional hazards regression model was used to calculate relative risks for each decrease of FFR by 0.05 Results: TLF occurred in 139 (13.5%) out of 1027 lesions at a median follow-up of 191 (82-297) days. The TLF group presented more often with diameter stenosis (DS) >70% (p<0.01), as compared with the non-TLF group. Mean FFR was significantly lower in the TLF than in the non-TLF group (0.63±0.14 vs. 0.75±0.16, p<0.001). At the multivariate Cox regression analysis (adjusted for age, gender hypertension, diabetes, and DS), FFR as a continuous function was significantly associated with TLF (HR [95% CI]: 0.023 [0.008-0.068]); in particular, each decrease in FFR by 0.05 was associated with a relative risk for TLF of 1.308 (95% CI 1.219-1.403, p<0.001). Conclusions: In pts with stable coronary disease, the actual value of FFR is an independent predictor of lesion-related clinical outcome. Each FFR decrease by 0.05 was associated with a 30% relative increase in the risk of one year TLF.