Aims: Contrast-flow quantitative flow ratio (cQFR) is a novel index of the functional severity of coronary stenosis, which can be calculated from three-dimensional quantitative coronary angiography. Previous studies have shown a high correlation between cQFR and fractional flow reserve. This study sought to investigate the prognostic value of the sum of cQFR in three vessels (3V-cQFR) in patients with stable coronary artery disease (CAD).
Methods and results: A total of 549 patients who underwent invasive coronary angiography and cQFR measurements in three vessels were analysed in the present study. Median cQFR of all cQFR-assessed vessels and 3V-cQFR of each patient were 0.94 (0.85-0.98) and 2.75 (2.62-2.87), respectively. During a median follow-up of 2.2 years, 57 patients experienced MACE. 3V-cQFR could provide prognostic information in the total cohort and among those without undergoing revascularisation as well. In a multivariate analysis, 3V-cQFR, high-sensitivity cardiac troponin-I and previous MI remained as independent predictors for MACE, and conventional angiographic scores did not.
Conclusions: 3V-cQFR could discriminate the risk for MACE in patients with stable CAD. 3V-cQFR calculated from routine invasive angiograms was feasible, and the prognostic implication could be more powerful than that of conventional angiographic scores.