Abstract
Coronary artery stenosis is a narrowing of coronary lumen space caused by an atherosclerotic lesion. Fractional flow reserve (FFR) is the gold standard metric to assess physiological significance of coronary stenosis, but requires an invasive procedure. Computational modeling in conjunction with patient-specific imaging demonstrates formation of regions of recirculatory flow distal to a stenosis, increasing mean blood residence time relative to uninhibited flow. A new computational parameter, mean blood residence time (BloodRT), was computed for 100 coronary artery segments for which FFR was known. A threshold for BloodRT was determined to assess the physiological significance of a stenosis, analogous to diagnostic threshold for FFR. Model sensitivity and specificity of BloodRT for diagnosis of hemodynamically significant coronary stenosis was 98% and 96% respectively, compared with FFR. When applied to clinical practice, this could potentially allow practicing cardiologists to accurately assess the severity of coronary stenosis without resorting to invasive techniques.
Highlights
Total patients Total vessels Age Male gender Hypertension Diabetes mellitus Current smoker History of prior myocardial infarction History of prior percutaneous coronary intervention (PCI) History of prior coronary artery disease (CAD) Hyperlipidemia family history Vessel disease Single-vessel Two-vessel Three-vessel total vessels is typically modeled as laminar, localized regions of turbulence can exist in a recirculation region, and not accounting for the turbulent energy dissipation may reduce the accuracy of the predicted pressure loss
We present here a new non-invasively determined metric, dimensionless B loodRT, to assess the physiological significance of coronary artery stenosis analogous to the coronary stenosis assessment based on FFR
We developed a new computational based metric to assess the physiological significance of coronary stenosis without the use of invasive pressure-wire measurement
Summary
Total patients Total vessels Age Male gender Hypertension Diabetes mellitus Current smoker (last 1 year) History of prior myocardial infarction History of prior PCI History of prior CAD Hyperlipidemia family history Vessel disease Single-vessel Two-vessel Three-vessel total vessels is typically modeled as laminar, localized regions of turbulence can exist in a recirculation region, and not accounting for the turbulent energy dissipation may reduce the accuracy of the predicted pressure loss. Deceleration of blood flow during the cardiac cycle yields large recirculation zones distal to stenosis leading to protracted path lengths and greater residence times. Cao et al.[18] measured increasing residence time of tracers downstream of stenosis using a laser light sheet flow visualization method with pseudo-color display. CFD can compute residence time in flow systems, which requires solving time dependent tracer concentrations after the velocity distribution is obtained. Conventional residence time theory is a measure of flow distribution at the exit of a continuous system whereas mean age theory provides spatial resolution throughout the interior of the flow domain. The method to determine the metric is presented here and is based on CFD in conjunction with patient specific imaging to compute mean residence time of blood passing through stenotic coronary artery segments. We tested our metric in one hundred coronary arteries with known pressure-wire FFR for clinical validation
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
