In this study, effects of serial stenosis on coronary hemodynamics were investigated in the human right coronary artery (RCA) using blood flow analysis. A 3-D model of a serial stenosed RCA was reconstructed based on multislice computerized tomography images. Numerical analysis examined the effect of multiple serial stenoses on the hemodynamic characteristics such as flow separation, pressure drop and FFR. Pressure loss associated with flow expansion after each constriction was large. Overall pressure drop increased from 1700 Pa (12.75 mmHg) at the end diastole to 11000 Pa (82.5 mmHg) at the peak systole. In two stenoses the corresponding pressure gradients werearound 30 mmHg and corresponded to the stenosis with FFR < 0.7 (associated to the sever stenosis). Severe stenosies caused large pressure drops across the throat. Blood flow distal to the stenosis was associated with fluctuations of the wall shear stress and vorticity.
Keywords: fractional flow reserve; hemodynamics; pressure drop; right coronary artery; serial stenosis.