Comparison of Instantaneous Wave-Free Ratio (iFR) and Fractional Flow Reserve (FFR) with respect to Their Sensitivities to Cardiovascular Factors: A Computational Model-Based Study

Figure 3

Model-simulated aortic and poststenosis coronary arterial pressure waves (a∼c), wave intensity in mid-LAD (d∼f), and poststenosis coronary microvascular resistance (g∼i) during iFR measurement under the control and two altered physiological conditions (one with a 67% increase in HR and the other with a 200% increase in aPWV). The wave-free period (WFP) during a cardiac cycle is highlighted by the gray shadow. The stenosis was present in mid-LAD, with the stenosis rate being fixed at 50% in all the simulations.