Fractional flow reserve (FFR)-guided percutaneous intervention is superior to standard assessment but remains underused. The authors have developed a novel "pseudotransient" analysis protocol for computing virtual fractional flow reserve (vFFR) based upon angiographic images and steady-state computational fluid dynamics. This protocol generates vFFR results in 189 s (cf >24 h for transient analysis) using a desktop PC, with <1% error relative to that of full-transient computational fluid dynamics analysis. Sensitivity analysis demonstrated that physiological lesion significance was influenced less by coronary or lesion anatomy (33%) and more by microvascular physiology (59%). If coronary microvascular resistance can be estimated, vFFR can be accurately computed in less time than it takes to make invasive measurements.
Keywords: CAD, coronary artery disease; CAG, coronary angiography; CFD, computational fluid dynamics; CMV, coronary microvasculature; FFR, fractional flow reserve; PCI, percutaneous coronary intervention; RoCA, rotational coronary angiography; computational fluid dynamics; coronary artery disease; coronary microvascular physiology; coronary modelling; coronary physiology; fractional flow reserve; mFFR, invasively measured fractional flow reserve; vFFR, virtual fractional flow reserve; vFFRps-trns, virtual fractional flow reserve computed with the pseudotransient steady-state method; vFFRsteady, virtual fractional flow reserve computed with steady-state CFD analysis and cycle mean values; vFFRtrns, virtual fractional flow reserve computed with full transient CFD; virtual fractional flow reserve.