a statistical trendp = 0.073
When only studies with an FFR cut-off of 0.9 were included (Additional file 1 : Figure S2), the results showed that patients in the low FFR group had significantly higher risk than the high FFR group for MACE (OR: 4.92, 95 % CI: 3.11–7.78, p < 0.0001), myocardial infarction (OR: 10.02, 95 % CI: 3.33–30.12, p < 0.0001), and a statistical trend towards higher risk for overall death (OR: 3.70, 95 % CI: 0.89–15.43, p = 0.073).