A study printed in the Circulation journal evaluated the independent and integrated value of maximal myocardial blood flow (MBF) and coronary flow reserve (CFR) for predicting cardiovascular death in patients with stable coronary artery disease. It was reported that CFR is a comparatively stronger predictor of cardiovascular mortality than maximal MBF, beyond traditional cardiovascular risk factors, left ventricular ejection fraction, myocardial scar and ischemia, rate-pressure product, type of radiotracer or stress agent used, and revascularization after scan. Concordant and discordant categories based on integrating CFR and maximal MBF help in identifying unique prognostic phenotypes of patients with known or suspected coronary artery disease.