Impact of plaque components on fractional flow reserve derived computed tomography (FFRCT) in severe coronary stenosis

Fractional flow reserve derived computed tomography (FFRCT) decreases across severe coronary stenosis. The diagnostic accuracy of FFRCT is high for severe coronary stenosis. We have experienced a case of no significant FFRCT changes even in severe coronary stenosis. A 75-year-old man showed severe stenosis (85% diameter stenosis) in the distal segment of the right coronary artery on both CT angiography and invasive coronary angiography. However, FFRCT showed no significant changes from the proximal (0.97) to the distal (0.95) even in the severe stenotic lesion. This patient had different features including the presence of a large acute marginal branch and significantly lower plaque components in the stenotic lesion compared with severe coronary stenosis in the same segment. A large bifurcation branch and/or proportion of plaque components can affect FFRCT hemodynamics.