A new scoring system for predicting FFR results

Background: Percutaneous coronary intervention (PCI) guided with fractional flow reserve (FFR) has shown to improve clinical outcomes. Although coronary angiogram is still the standard method for guiding PCI, the visual and functional severities are not always correlated, suggesting there are additional visual factors that affect functional ischemia. Method: To evaluate the angiographic predictors for positive FFR in stenotic lesions, angiographic characteristics of 260 consecutive patients (362 lesions) who underwent FFR testing from April 2009 to September 2012 were analyzed. After logistic regression analysis, the following independent predictors were identified: stenosis >75% (OR 4.68, p 20mm (OR 1.92, p<0.0001), and distance from ostium <20mm (OR 1.37, p<0.05). Using these parameters, the STABLED score (Stenosis 2 points, TAndem lesion 1 point, Bifurcation 1 point, LEsion length 1 point, Distance from ostium 1 point) was determined and validated for efficacy. Results: The area under receiver-operator curve for probability of positive FFR by the STABLED score is 0.84. A STABLED score≥3 has 71.6% sensitivity and 84.1% specificity for predicting positive FFR, and its positive predictive value is 77.1%. View this table: Angiographic predictors of FFR results Conclusion: Specific angiographic features are applicable for predicting functional ischemia. This new STABLED score determined only by visual angiography, correlates well with FFR testing.