Issue title: Workshop: Breaking Symmetry in Haemodynamics, London, UK, 23–24 April 2001
Article type: Research Article
Authors: Caro, Colin; | Jeremy, Jamie | Watkins, Nick | Bulbulia, Richard | Angelini, Gianni | Smith, Frank | Wan, Song | Yim, Anthony | Sherwin, Spencer | Peiró, Joaquim | Papaharilaou, Yannis; | Falzon, Brian | Giordana, Sergio | Griffiths, Clydd
Affiliations: Department of Bioengineering, Imperial College, London, UK | Department of Aeronautics, Imperial College, London, UK | Bristol Heart Institute, University of Bristol, UK | Department of Surgery, Bristol Royal Infirmary, UK | Department of Surgery, Prince of Wales Hospital, Hong Kong
Note: [] Address for correspondence: Prof. C.G. Caro, Sir Leon Bagrit Centre, Department of Bioengineering, Imperial College, Exhibition Road, London SW7 2BX, UK. Tel.: +44 207 594 5180; Fax: +44 207 584 6897; E‐mail: [email protected].
Abstract: The long‐term success of arterial bypass grafting with autologous saphenous veins is limited by neointimal hyperplasia (NIH), which seemingly develops preferentially at sites where hydrodynamic wall shear is low. Placement of a loose‐fitting, porous stent around end‐to‐end, or end‐to‐side, autologous saphenous vein grafts on the porcine common carotid artery has been found significantly to reduce NIH, but the mechanism is unclear. In a preliminary study, we implanted autologous saphenous vein grafts bilaterally on the common carotid arteries of pigs, placing a stent around one graft and leaving the contralateral graft unstented. At sacrifice 1 month post implantation, the grafts were pressure fixed in situ and resin casts were made. Unstented graft geometry was highly irregular, with non‐uniform dilatation, substantial axial lengthening, curvature, kinking, and possible long‐pitch helical distortion. In contrast, stented grafts showed no major dilatation, lengthening or curvature, but there was commonly fine corrugation, occasional slight kinking or narrowing of segments, and possible long‐pitch helical distortion. Axial growth of grafts against effectively tethered anastomoses could account for these changes. CFD studies are planned, using 3D MR reconstructions, on the effects of graft geometry on the flow. Abnormality of the flow could favour the development of vascular pathology, including NIH.
Keywords: Graft geometry, graft casts, graft elongation, graft buckling
Journal: Biorheology, vol. 39, no. 3-4, pp. 507-512, 2002
