Reduced　cardiac　output　(CO)　always　occurs　in　aortic　valve　diseases.　The　hemodynamics　of　aortic　valve　is　affected　by　reduced　CO,　causing　secondary　valvular　diseases.　In　this　paper,　a　three-dimensional　reconstruction　of　aortic　root　geometric　model　with　left　coronary　artery　is　complished　based　on　medical　imaging　data,　a　highly　smooth　and　transparent　aortic　root　experimental　model　is　casted,　and　an　in　vitro　pulsating　circulation　system　is　constructed.　Particle　image　velocimetry　(PIV)　is　used　to　investigate　the　effect　of　CO　on　hemodynamics　of　aortic　valve　with　or　without　the　left　coronary　artery,　such　as　the　velocity,　viscous　shear　stress　(VSS),　Reynolds　shear　stress　(RSS),　and　so　on.　The　results　show　that　aortic　sinus　hemodynamics　are　influenced　by　left　coronary　artery　that　the　presence　of　left　coronary　artery　changes　the　vortex　and　vorticity　in　the　sinus.　In　the　case　of　the　presence　of　left　coronary　artery,　fluids　in　the　aortic　sinus　flows　out　through　the　left　coronary　artery　which　leads　to　vortex　gradually　disappears　and　vorticity　early　decreases.　At　the　peak　systolic,　regions　of　positive　and　negative　VSS　are　exist　in　both　sides　of　the　centrosymmetric　systolic　jet　and　RSS　is　especially　elevated　in　the　ascending　aorta　on　the　side　of　left　coronary　artery.　In　addition,　the　hemodynamics　of　aortic　valve,　such　as　the　velocity,　VSS　and　RSS,　are　significantly　affected　by　the　CO.　The　maximum　velocity,　VSS　and　RSS　increase　with　the　increasing　of　CO,　namely,　the　maximum　velocity　is　0.98,　1.13,　1.21　and　1.37　m/s,　the　maximum　VSS　is　0.87,　0.95,　0.96　and　1.02　N/m2,　and　the　maximum　RSS　is　103.76,　116.25,　138.68　and　146.55　N/m2　when　CO=2.1,　2.8,　3.5　and　4.2　L/min,　respectively.　At　low　CO,　the　values　of　transvalvular　flow　velocity　and　VSS　of　aortic　valve　are　small,　which　may　easily　lead　to　thrombosis.　The　research　findings　can　provide　theoretical　references　for　the　aortic　valve　implantation.　©　2019,　Chinese　Journal　of　Theoretical　and　Applied　Mechanics　Press.　All　right　reserved.