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Medical & Biological Engineering & Computing

, Volume 45, Issue 9, pp 819–827 | Cite as

A procedure to simulate coronary artery bypass graft surgery

  • Fernando Cacho
  • Manuel Doblaré
  • Gerhard A. Holzapfel
Original Article

Abstract

In coronary artery bypass graft (CABG) surgery the involved tissues are overstretched, which may lead to intimal hyperplasia and graft failure. We propose a computational methodology for the simulation of traditional CABG surgery, and analyze the effect of two clinically relevant parameters on the artery and graft responses, i.e., incision length and insertion angle for a given graft diameter. The computational structural analyses are based on actual three-dimensional vessel dimensions of a human coronary artery and a human saphenous vein. The analyses consider the structure of the end-to-side anastomosis, the residual stresses and the typical anisotropic and nonlinear vessel behaviors. The coronary artery is modeled as a three-layer thick-walled tube. The finite element method is employed to predict deformation and stress distribution at various stages of CABG surgery. Small variations of the arterial incision have relatively big effects on the size of the arterial opening, which depends solely on the residual stress state. The incision length has a critical influence on the graft shape and the stress in the graft wall. Stresses at the heel region are higher than those at the toe region. The changes in the mechanical environment are severe along all transitions between the venous tissue and the host artery. Particular stress concentrations occur at the incision ends. The proposed computational methodology may be useful in designing a coronary anastomotic device for reducing surgical trauma. It may improve the quantitative knowledge of vessel diseases and serve as a tool for virtual planning of vascular surgery.

Keywords

CABG End-to-side anastomosis Finite element method Intimal hyperplasia Solid mechanics 

Notes

Acknowledgments

This research was financed by the Spanish Ministry of Science and Education under Project No. CICYT DPI2004-07410-C03 and Grant/Contract No. FP2000-5317 for FC; and by the DISHEART European Project (CRAFT-FP6-2002-SME-1).

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Copyright information

© International Federation for Medical and Biological Engineering 2007

Authors and Affiliations

  • Fernando Cacho
    • 1
    • 2
  • Manuel Doblaré
    • 2
  • Gerhard A. Holzapfel
    • 3
    • 4
  1. 1.Institute for Structural Analysis, Computational BiomechanicsGraz University of TechnologyGrazAustria
  2. 2.Group of Structural Mechanics and Materials Modeling, Aragon Institute of Engineering Research (I3A)University of ZaragozaSaragossaSpain
  3. 3.Institute for Biomechanics, Center for Biomedical EngineeringGraz University of TechnologyGrazAustria
  4. 4.Department of Solid Mechanics, School of Engineering SciencesRoyal Institute of TechnologyStockholmSweden

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