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.
