title: Flow patterns at stented coronary bifurcations: computational fluid dynamics analysis.
abstract: BACKGROUND
  The ideal bifurcation stenting technique is not established, and data on the hemodynamic characteristics at stented bifurcations are limited.
  
  
  RESULTS
  We used computational fluid dynamics analysis to assess hemodynamic parameters known affect the risk of restenosis and thrombosis at coronary bifurcations after the use of various single- and double-stenting techniques. We assessed the distributions and surface integrals of the time averaged wall shear stress (TAWSS), oscillatory shear index (OSI), and relative residence time (t(r)). Single main branch stenting without side branch balloon angioplasty or stenting provided the most favorable hemodynamic results (integrated values of TAWSS=4.13·10(-4) N, OSI=7.52·10(-6) m(2), t(r)=5.57·10(-4) m(2)/Pa) with bifurcational area subjected to OSI values >0.25, >0.35, and >0.45 calculated as 0.36 mm(2), 0.04 mm(2), and 0 mm(2), respectively. Extended bifurcation areas subjected to these OSI values were seen after T-stenting: 0.61 mm(2), 0.18 mm(2), and 0.02 mm(2), respectively. Among the considered double-stenting techniques, crush stenting (integrated values of TAWSS=1.18·10(-4) N, OSI=7.75·10(-6) m(2), t(r)=6.16·10(-4) m(2)/Pa) gave the most favorable results compared with T-stenting (TAWSS=0.78·10(-4) N, OSI=10.40·10(-6) m(2), t(r)=6.87·10(-4) m(2)/Pa) or the culotte technique (TAWSS=1.30· 10(-4) N, OSI=9.87·10(-6) m(2), t(r)=8.78·10(-4) m(2)/Pa).
  
  
  CONCLUSIONS
  In the studied models of computer simulations, stenting of the main branch with our without balloon angioplasty of the side branch offers hemodynamic advantages over double stenting. When double stenting is considered, the crush technique with the use of a thin-strut stent may result in improved immediate hemodynamics compared with culotte or T-stenting.
authors: Department of Cardiology, Athens Euroclinic, 9 Athanassiadou St., Athens, Greece. dkatritsis@euroclinic.gr
authors: Demosthenes G
authors: DG
authors: Katritsis
authors: Andreas
authors: A
authors: Theodorakakos
authors: Ioannis
authors: I
authors: Pantos
authors: Manolis
authors: M
authors: Gavaises
authors: Nicos
authors: N
authors: Karcanias
authors: Efstathios P
authors: EP
authors: Efstathopoulos
mesh_terms: D015906:Angioplasty, Balloon, Coronary; D003198:Computer Simulation; D003324:Coronary Artery Disease / Q000453:epidemiology / Q000503:physiopathology / Q000628:therapy; D003326:Coronary Circulation / Q000502:physiology*; D023903:Coronary Restenosis / Q000453:epidemiology / Q000503:physiopathology; D003331:Coronary Vessels / Q000502:physiology; D054855:Drug-Eluting Stents; D000068338:Everolimus; D006801:Humans; D057446:Hydrodynamics; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D008955:Models, Cardiovascular; D012307:Risk Factors; D020123:Sirolimus / Q000031:analogs & derivatives / Q000627:therapeutic use
chemical_list: D007166:Immunosuppressive Agents; D000068338:Everolimus; D020123:Sirolimus