Influence of the position of the distal pressure measurement point on the Fractional Flow Reserve using in-silico simulations

Abstract

Coronary stenosis is mainly responsible for myocardial ischemia as the blood supply to a portion of the heart stops or is severely reduced. The Fractional Flow Reserve is the benchmark for the hemodynamic significance assessment of coronary stenoses. Its value is employed as a gatekeeper/planning tool for revascularization in clinical practice.Non-invasive alternatives have been successfully proposed to guide cardiologists. However, simulation values are not accurate enough in the 0.75–0.85 range, so invasive Fractional Flow Reserve should be used.Several authors argue about where distal pressure should be measured. Therefore, our aim is to use simulation to assess how this value changes and to detect the correct measurement region.First, we have adjusted the simulation method to the segmentations of two patients whose invasive Fractional Flow Reserve is known. We then extended our analysis to four patients and obtained the simulated value at multiple points distal to the stenosis. This is an advantage over invasive measurements, whose locations are restricted. The results are also essential for locating the best region for invasive distal pressure measurements.We propose a hybrid invasive and in-silico procedure that would avoid false results and prevent cardiologists from making erroneous clinical decisions.