title: Numerical investigation of the effect of stenosis geometry on the coronary diagnostic parameters.
abstract: The present study deals with the functional severity of a coronary artery stenosis assessed by the fractional flow reserve (FFR). The effects of different geometrical shapes of lesion on the diagnostic parameters are unknown. In this study, 3D computational simulation of blood flow in three different geometrical shapes of stenosis (triangular, elliptical, and trapezium) is considered in steady and transient conditions for 70% (moderate), 80% (intermediate), and 90% (severe) area stenosis (AS). For a given percentage AS, the variation of diagnostic parameters which are derived from pressure drop across the stenosis was found in three different geometrical shapes of stenosis and it was observed that FFR is higher in triangular shape and lower in trapezium shape. The pressure drop coefficient (CDP) was higher in trapezium shape and lower in triangular model whereas the LFC shows opposite trend. From the clinical perspective, the relationship between percentage AS and FFR is linear and inversely related in all the three models. A cut-off value of 0.75 for FFR was observed at 76.5% AS in trapezium model, 79.5% in elliptical model, and 82.7% AS for the triangular shaped model. The misinterpretation of the functional severity of the stenosis is in the region of 76.5%-82.7 % AS from different shapes of stenosis models.
authors.affiliation: Department of Mechanical Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Sarfaraz
authors.initials: S
authors.lastname: Kamangar
authors.affiliation: Department of Mechanical Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Govindaraju
authors.initials: G
authors.lastname: Kalimuthu
authors.affiliation: Department of Mechanical Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Irfan Anjum
authors.initials: IA
authors.lastname: Badruddin
authors.affiliation: Department of Mechanical Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: A
authors.initials: A
authors.lastname: Badarudin
authors.affiliation: Faculty of Engineering & Technology, Multimedia University, 75450 Bukit Beruang, Malacca, Malaysia.
authors.forename: N J Salman
authors.initials: NJ
authors.lastname: Ahmed
authors.affiliation: Department of Mechanical Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: T M Yunus
authors.initials: TM
authors.lastname: Khan
mesh_terms: D000465:Algorithms; D001783:Blood Flow Velocity; D001794:Blood Pressure; D003198:Computer Simulation; D023921:Coronary Stenosis / Q000175:diagnosis / Q000473:pathology* / Q000503:physiopathology*; D003331:Coronary Vessels / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D008953:Models, Anatomic; D008955:Models, Cardiovascular; D012720:Severity of Illness Index