Numerical simulation and clinical implications of stenosis in coronary blood flow

Abstract

Fractional flow reserve (FFR) is the gold standard to guide coronary interventions. However it can only be obtained via invasive angiography. The objective of this study is to propose a noninvasive method to determine FF R CT by combining computed tomography angiographic (CTA) images and computational fluid dynamics (CFD) technique. Utilizing the method, this study explored the effects of diameter stenosis (DS), stenosis length, and location on FF R CT. The baseline left anterior descending (LAD) model was reconstructed from CTA of a healthy porcine heart. A series of models were created by adding an idealized stenosis (with DS from 45% to 75%, stenosis length from 4 mm to 16 mm, and at 4 locations separately). Through numerical simulations, it was found that FF R CT decreased (from 0.89 to 0.74), when DS increased (from 45% to 75%). Similarly, FF R CT decreased with the increase of stenosis length and the stenosis located at proximal position had lower FF R CT than that at distal position. These findings are consistent with clinical observations. Applying the same method on two patients' CTA images yielded FF R CT close to the FFR values obtained via invasive angiography. The proposed noninvasive computation of FF R CT is promising for clinical diagnosis of CAD. © 2014 Jun-Mei Zhang et al.