The　extracardiac　Fontan　connection　(EFC)　is　an　effective　treatment　for　congenital　single　ventricle　heart　defects.　Numerous　studies　have　sought　to　optimize　the　EFC　design.　However,　the　optimal　design　of　EFC　remains　uncertain.　This　study　aims　to　examine　the　influence　of　bypass　angles　between　the　inferior　vena　cava　(IVC)　and　right　pulmonary　artery　(RPA),　and　the　angles　between　the　IVC　and　superior　vena　cava　(SVC),　on　hemodynamics.　Furthermore,　this　study　demonstrates　a　methodology　for　cardiovascular　surgical　planning.　First,　a　three-dimensional　anatomical　geometry　was　reconstructed　from　the　medical　images　of　a　patient　with　single　ventricle　heart　defects.　Second,　based　on　haptic　deformations,　six　computational　models　were　virtually　generated.　Third,　numerical　simulations　were　conducted　using　computational　fluid　dynamics　through　the　finite　volume　method.　Finally,　hemodynamic　parameters　were　obtained　and　evaluated.　The　hemodynamic　parameters,　including　the　flow　patterns,　streamlines,　and　swirling　flow,　were　obtained.　Meanwhile,　the　energy　loss　and　flow　distributions　of　vena　cava　blood　were　calculated.　First,　the　hepatic　artery　blood　distribution　to　two　lungs　and　the　flow　ratio　of　the　left　pulmonary　artery　to　RPA　are　sensitive　to　the　angle　between　the　IVC　and　RPA　and　not　to　that　between　the　IVC　and　SVC.　Second,　energy　dissipation　is　mainly　sensitive　to　the　angle　between　the　IVC　and　SVC　and　not　to　that　between　the　IVC　and　RPA.　Third,　an　appropriate　increase　in　the　angle　between　the　IVC　and　RPA　or　that　between　the　IVC　and　SVC　may　lead　to　optimal　options.　This　study　is　useful　for　surgeons　in　evaluating　optimal　Fontan　options.　Copyright　(c)　2012　John　Wiley　&　Sons,　Ltd.