Title | Improved prediction of disturbed flow via hemodynamically-inspired geometric variables. |
Publication Type | Journal Article |
Year of Publication | 2012 |
Authors | Bijari PB, Antiga L, Gallo D, Wasserman BA, Steinman DA |
Journal | J Biomech |
Volume | 45 |
Issue | 9 |
Pagination | 1632-7 |
Date Published | 2012 Jun 01 |
ISSN | 1873-2380 |
Keywords | Adult, Carotid Arteries, Computer Simulation, Hemorheology, Humans, Models, Cardiovascular, Regional Blood Flow, Young Adult |
Abstract | Arterial geometry has long been considered as a pragmatic alternative for inferring arterial flow disturbances, and their impact on the natural history and treatment of vascular diseases. Traditionally, definition of geometric variables is based on convenient shape descriptors, with only superficial consideration of their influence on flow and wall shear stress patterns. In the present study we demonstrate that a more studied consideration of the actual (cf. nominal) local hemodynamics can lead to substantial improvements in the prediction of disturbed flow by geometry. Starting from a well-characterized computational fluid dynamics (CFD) dataset of 50 normal carotid bifurcations, we observed that disturbed flow tended to be confined proximal to the flow divider, whereas geometric variables previously shown to be significant predictors of disturbed flow included features distal to the flow divider in their definitions. Flaring of the bifurcation leading to flow separation was redefined as the maximum relative expansion of the common carotid artery (CCA), proximal to the flow divider. The beneficial effect of primary curvature on flow inertia, via suppression of flow separation, was characterized by the in-plane tortuosity of CCA as it enters the flare region. Multiple linear regressions of these redefined geometric variables against various metrics of disturbed flow revealed R(2) values approaching 0.6, better than the roughly 0.3 achieved using the conventional shape-based variables, while maintaining their demonstrated real-world reproducibility. Such a hemodynamically-inspired approach to the definition of geometric variables may reap benefits for other applications where geometry is used as a surrogate marker of local hemodynamics. |
DOI | 10.1016/j.jbiomech.2012.03.030 |
Alternate Journal | J Biomech |
PubMed ID | 22552156 |
PubMed Central ID | PMC3371282 |
Grant List | N01HC55020 / HL / NHLBI NIH HHS / United States N01HC55018 / HL / NHLBI NIH HHS / United States N01-HC-55022 / HC / NHLBI NIH HHS / United States N01-HC-55016 / HC / NHLBI NIH HHS / United States U01 HL075572 / HL / NHLBI NIH HHS / United States N01-HC-55019 / HC / NHLBI NIH HHS / United States N01-HC-55015 / HC / NHLBI NIH HHS / United States MOP-62934 / CAPMC / CIHR / Canada N01HC55019 / HL / NHLBI NIH HHS / United States U01HL075572-01 / HL / NHLBI NIH HHS / United States N01HC55022 / HL / NHLBI NIH HHS / United States N01-HC-55021 / HC / NHLBI NIH HHS / United States U01 HL075572-01 / HL / NHLBI NIH HHS / United States N01HC55015 / HL / NHLBI NIH HHS / United States N01-HC-55020 / HC / NHLBI NIH HHS / United States N01HC55016 / HL / NHLBI NIH HHS / United States N01-HC-55018 / HC / NHLBI NIH HHS / United States N01HC55021 / HL / NHLBI NIH HHS / United States |