Local hemodynamics and intimal hyperplasia at the venous side of a porcine arteriovenous shunt

  • Authors:
  • Themistoklis A. Manos;Dimitrios P. Sokolis;Athina T. Giagini;Constantinos H. Davos;John D. Kakisis;Eleftherios P. Kritharis;Nikos Stergiopulos;Panayotis E. Karayannacos;Sokrates Tsangaris

  • Affiliations:
  • Laboratory of Biofluid-Mechanics and Biomedical Engineering, National Technical University of Athens, Athens, Greece;Center of Experimental Surgery, Foundation of Biomedical Research, Academy of Athens, Athens, Greece;Center of Experimental Surgery, Foundation of Biomedical Research, Academy of Athens, Athens, Greece;Clinical Research Center, Foundation of Biomedical Research, Academy of Athens, Athens, Greece;3rd Department of Surgery, University of Athens School of Medicine, Attikon University Hospital, Athens, Greece;Laboratory of Biofluid-Mechanics and Biomedical Engineering, National Technical University of Athens, Athens, Greece;Laboratory of Hemodynamics and Cardiovascular Technology, Swiss Federal Institute of Technology, Lausanne, Switzerland;Center of Experimental Surgery, Foundation of Biomedical Research, Academy of Athens, Athens, Greece;Laboratory of Biofluid-Mechanics and Biomedical Engineering, National Technical University of Athens, Athens, Greece

  • Venue:
  • IEEE Transactions on Information Technology in Biomedicine - Special section on new and emerging technologies in bioinformatics and bioengineering
  • Year:
  • 2010

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Abstract

Venous anastomotic intimal hyperplasia (IH) observed in the arteriovenous shunt (AVS) has been associated with disturbed hemodynamics. This study aims to correlate hemodynamics with wall histology and wall mechanics by examining the flow field in AVS with computational fluid dynamics using experimental data taken from in vivo experiments. Input data to the computational model were obtained in vivo one month after AVS creation; adjacent vessels were submitted to histological and mechanical examination. The 3-D shunt geometry was determined using biplane angiography. Ultrasound measurements of flow rates were performed with perivascular flow probes and pressures were recorded through intravascular catheters. These data were considered as boundary conditions for calculation of the unsteady flow field. Numerical findings are suggestive of strong Dean vortices toward both vein flow exits, verified by color Doppler. The high wall shear stresses (WSSs) and their gradients appear to be related to areas of IH and vessel wall stiffening, as evidenced in preliminary histological and mechanical studies of the venous wall. Additionally, suture line hyperplasia seems to be aggravated by the high WSS gradients noted at the transition line from graft to vein.