7th Dutch Bio-Medical Engineering Conference

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11:15
15 mins

High-Risk Coronary Plaque Development Is Related to Multi-Directional Shear Stress in an Atherosclerotic Pig Model
Ayla Hoogendoorn, Annette Kok, Eline Hartman, Suze-Anne Korteland, Lorena Casadonte, Adriaan Coenen, Frank Gijsen, Dirk Jan Duncker, Antonius van der Steen, Jolanda Wentzel

Session: Arteries
Session starts: Thursday 24 January, 10:30
Presentation starts: 11:15
Room: Lecture room 536

Ayla Hoogendoorn (Biomedical Engineering, ErasmusMC, Rotterdam, NL)
Annette Kok (Biomedical Engineering, ErasmusMC, Rotterdam, NL)
Eline Hartman (Biomedical Engineering, ErasmusMC, Rotterdam, NL)
Suze-Anne Korteland (Biomedical Engineering, ErasmusMC, Rotterdam, NL)
Lorena Casadonte (Medical Physics, AMC, Amsterdam, NL)
Adriaan Coenen (Radiology, ErasmusMC, Rotterdam, NL)
Frank Gijsen (Biomedical Engineering, ErasmusMC, Rotterdam, NL)
Dirk Jan Duncker (Experimental Cardiology, ErasmusMC, Rotterdam, NL)
Antonius van der Steen (Biomedical Engineering, ErasmusMC, Rotterdam, NL)
Jolanda Wentzel (Biomedical Engineering, ErasmusMC, Rotterdam, NL)

Abstract:
Background – Although time averaged shear stress (SS) is established for its involvement in atherosclerotic plaque development, not much information is available on the influence of multi-directionality of shear stress. We investigated the influence of five different multidirectional SS parameters on plaque development and composition. Therefore, we used an adult porcine model of atherosclerosis in which serial imaging was performed and histology was used to assess plaque growth and composition in the coronary arteries. Methods – 10 adult familial hypercholesterolemic swine were put on a high fat diet for 12 months and underwent 3-vessel CT-scan, near-infrared spectroscopy intravascular ultrasound (NIRS-IVUS) imaging and flow measurements at 3 time points. An anatomically optimized 3D geometry of the arterial lumen at baseline, in combination with local flow measurements, was used for calculation of the SS metrics (time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI), relative residence time (RRT), trans-wall shear stress (transWSS) and cross-flow index (CFI)). For the analysis, the arteries were divided into 3mm - 45° sectors (n=3627) which were split into low, mid or high levels of each SS metric per individual artery. IVUS and histology were used to correlate plaque thickness changes and composition to baseline SS levels. Results – Half of the pigs developed large, lumen intruding plaques and in these fast responders, IVUS-based plaque growth was significantly more pronounced in areas of low TAWSS and high OSI/RRT/CFI (p<0.05). In the slow responding animals no relationship between plaque growth and the five SS metrics was observed. In the fast responders, the most advanced plaque type (fibrous cap atheroma (FCA)) was located at higher absolute levels of OSI and CFI compared to less advanced plaques (p<0.05). These results were supported by a more detailed histological analysis, showing that plaques with the highest lipid, macrophage and necrotic core area were exposed to low TAWSS and high OSI and RRT (p<0.05). CFI and transWSS appeared not to influence plaque composition (p=NS). Conclusions – The data derived from this study support the role of multidirectional shear stress in the development of coronary atherosclerosis with regard to plaque size and composition.