title: Optimal bypass graft design for left anterior descending and diagonal territory in multivessel coronary disease.
abstract: OBJECTIVE
  Coronary artery bypass grafting for multivessel disease requires an appropriate graft design to avoid the competition of flow between the graft and the native vessel in order to achieve a sufficient coronary flow and durable graft patency.
  
  
  METHODS
  Three-dimensional computational models of the left coronary artery were created based on the angiographic data. Three stenosis patterns of 75 and 90% combinations were created in the left anterior descending artery (LAD), the diagonal branch (Dx) and the circumflex artery (LCx). The left internal thoracic artery (LITA) was anastomosed to the LAD, and separate saphenous vein grafts (SVGs) were anastomosed to the Dx and the LCx in the 'Independent' model. The 'Sequential' model included sequential SVG anastomoses to the Dx and the LCx with a left internal thoracic artery-left anterior descending artery bypass, and Y-composite arterial grafts to LAD and Dx were created in the 'Composite' model.
  
  
  RESULTS
  The 'Independent' model had high reverse flow from the Dx to the LAD in systole, resulting in decreased LITA flow when Dx stenosis was mild. The 'Sequential' model also had reverse flow in diastole, resulting in additional LAD flow. The 'Composite' model distributed increased flow to the Dx when Dx stenosis was severe, resulting in decreased flow to the LAD.
  
  
  CONCLUSIONS
  Systematic flow evaluation is beneficial for determining the optimal bypass graft arrangement in patients with multivessel disease. Individual SVG anastomoses to the Dx and the LCx are not desirable when Dx stenosis is not severe and a Y-composite arterial graft to the LAD and the Dx is not desirable when Dx stenosis is severe.
authors.affiliation: Department of Cardiovascular Surgery, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan Department of Cardiac Surgery, Graduate School of Medicine, The University of Tokyo, Bunkyo, Tokyo, Japan.
authors.forename: Sachi
authors.initials: S
authors.lastname: Koyama
authors.affiliation: Department of Cardiovascular Surgery, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan Department of Hemodynamic Analysis, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan keiichiitatani@gmail.com.
authors.forename: Keiichi
authors.initials: K
authors.lastname: Itatani
authors.affiliation: Department of Cardiology, Hokkaido Cardiovascular Hospital, Hokkaido, Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Yamamoto
authors.affiliation: Department of Hemodynamic Analysis, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan.
authors.forename: Shohei
authors.initials: S
authors.lastname: Miyazaki
authors.affiliation: Department of Cardiovascular Surgery, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Kitamura
authors.affiliation: Department of Cardiovascular Surgery, Mitsui Memorial Hospital, Chiyoda, Tokyo, Japan.
authors.forename: Tuyoshi
authors.initials: T
authors.lastname: Taketani
authors.affiliation: Department of Cardiac Surgery, Graduate School of Medicine, The University of Tokyo, Bunkyo, Tokyo, Japan.
authors.forename: Minoru
authors.initials: M
authors.lastname: Ono
authors.affiliation: Department of Cardiovascular Surgery, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan.
authors.forename: Kagami
authors.initials: K
authors.lastname: Miyaji
mesh_terms: D001794:Blood Pressure; D003198:Computer Simulation; D017023:Coronary Angiography; D001026:Coronary Artery Bypass / Q000379:methods*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D003326:Coronary Circulation; D023921:Coronary Stenosis / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D008955:Models, Cardiovascular; D011237:Predictive Value of Tests; D011857:Radiographic Image Interpretation, Computer-Assisted; D025321:Surgery, Computer-Assisted
keywords: Computer applications (simulation); Coronary artery bypass graft; Ischaemic heart disease; Modelling (computer); Revascularization (coronary artery)