title: Patient-Specific Simulations Reveal Significant Differences in Mechanical Stimuli in Venous and Arterial Coronary Grafts.
abstract: Mechanical stimuli are key to understanding disease progression and clinically observed differences in failure rates between arterial and venous grafts following coronary artery bypass graft surgery. We quantify biologically relevant mechanical stimuli, not available from standard imaging, in patient-specific simulations incorporating non-invasive clinical data. We couple CFD with closed-loop circulatory physiology models to quantify biologically relevant indices, including wall shear, oscillatory shear, and wall strain. We account for vessel-specific material properties in simulating vessel wall deformation. Wall shear was significantly lower (p = 0.014*) and atheroprone area significantly higher (p = 0.040*) in venous compared to arterial grafts. Wall strain in venous grafts was significantly lower (p = 0.003*) than in arterial grafts while no significant difference was observed in oscillatory shear index. Simulations demonstrate significant differences in mechanical stimuli acting on venous vs. arterial grafts, in line with clinically observed graft failure rates, offering a promising avenue for stratifying patients at risk for graft failure.
authors.affiliation: Department of Mechanical and Aerospace Engineering, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA.|Departments of Pediatrics and Bioengineering, Institute for Computational and Mathematical Engineering, Stanford University, Stanford, CA, 94305, USA.
authors.forename: Abhay B
authors.initials: AB
authors.lastname: Ramachandra
authors.affiliation: Department of Medicine, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA.
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Kahn
authors.affiliation: Departments of Pediatrics and Bioengineering, Institute for Computational and Mathematical Engineering, Stanford University, Clark Center E100B 318 Campus Drive, Stanford,, CA, 94305-5428, USA. amarsden@stanford.edu.
authors.forename: Alison L
authors.initials: AL
authors.lastname: Marsden
mesh_terms: D000328:Adult; D000368:Aged; D000072226:Computed Tomography Angiography; D017023:Coronary Angiography / Q000379:methods; D001026:Coronary Artery Bypass; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D003326:Coronary Circulation; D015150:Echocardiography, Doppler; D005260:Female; D020342:Finite Element Analysis; D006801:Humans; D008297:Male; D008323:Mammary Arteries / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000637:transplantation*; D040542:Mechanotransduction, Cellular; D008875:Middle Aged; D008953:Models, Anatomic; D008955:Models, Cardiovascular; D061330:Multidetector Computed Tomography; D009716:Numerical Analysis, Computer-Assisted; D066230:Patient-Specific Modeling; D012501:Saphenous Vein / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000637:transplantation*; D013314:Stress, Mechanical; D016896:Treatment Outcome
keywords: Computational fluid dynamics; Coronary bypass; Hemodynamics; Mammary artery; Multiscale model; Patient-specific modeling; Risk stratification; Vein graft; Wall shear