Calculation of Fractional Flow Reserve (FFR) using CT Angiography Images /

Abstract

Fractional flow reserve (FFR) is a novel and clinically useful technique used in coronary catheterization to measure pressure differences across coronary artery stenosis (narrowing, usually due to atherosclerosis). It is considered now-a-days, as a gold standard to assess whether any particular stenosis is responsible for inducible ischemia. Angiography can be used additionally for the visual evaluation of the inner diameter of a vessel. In ischemic heart disease, identification of narrowing of vessel for potential lesion is not straightforward and consumes a lot of time. Fractional flow reserve on the contrary, provides a functional evaluation by measuring the pressure decline caused by a vessel narrowing. The main objective of the study is to calculate FFR non-invasively to help in the prognosis of pressure drop of blood flow across stenosis. This will overcome the previously established invasive procedures of calculating FFR normally done in cardiac catheterisation. The exceptionality of this work undertakes modelling of non-Newtonian pulsatile blood flow. Present work incorporates the modelling of 3D coronary artery using CT Angiography DICOM images and simulation of non-Newtonian, pulsatile and non-pulsatile blood flows using computational fluid dynamics (CFD). The results show that the transient, non-Newtonian pulsatile blood flows give more accurate results to mimic invasive FFR as compared to steady and transient non-pulsatile blood flows. The correlation of results obtained from this study are 100% in agreement with those obtained from invasive Angiography based FFR. We hope this non-invasive method will provide new pathway as a tool for diagnosis and evaluation of the narrowing caused by stenosis is coronary arteries.