Hemodynamic characterization of transient blood flow in righ

Numerical Simulation of Flow in Curved CoronaryArteries with Progressive Amounts of StenosisUsing Fluid-Structure Interaction Modelling

ComputersinBiologyandMedicine64(2015)117–126

ContentslistsavailableatScienceDirect

ComputersinBiologyandMedicine

journalhomepage:http://doc.guandang.net/locate/cbm

Hemodynamiccharacterizationoftransientblood owinrightcoronaryarterieswithvaryingcurvatureandside-branchbifurcationangles

GuiyingLiua,b,JianhuangWub,n,DhanjooN.Ghistab,WenhuaHuanga,KelvinK.L.Wongb,c,nn

GuangdongProvincialKeyLaboratoryofMedicalBiomechanics,DepartmentofAnatomy,SchoolofBasicMedicineScience,SouthernMedicalUniversity,GuangzhouDadaoNorthRoad1838,Guangzhou510515,PRChinab

ShenzhenInstitutesofAdvancedTechnology,ChineseAcademyofSciences,1068XueyuanBoulevard,XiliNanshan,Shenzhen518055,PRChinac

SchoolofComputerScienceandSoftwareEngineering,TheUniversityofWesternAustralia,35StirlingHighway,Crawley6009,WA,Australia

a

articleinfo

Articlehistory:

Received7March2015Accepted11June2015Keywords:

ComputationalsimulationParametricanalysisRightcoronaryarterySide-branchbifurcationWallshearstress

Wallpressuregradient

abstract

Hemodynamicsplaysacriticalroleinthedevelopmentandprogressionofplaquesthatarepronetositesofarterialcurvaturesandbranchbifurcations.Theoccurrenceofatherosclerosisatcurvaturesofcoronaryarteriesandatthebifurcationsitesoftheirbranchesareofmedicalimportance.Inthisstudy,wehaveemployedcomputersimulationcoupledwithaparametricanalysistorigorouslyquantifythetransientwallshearstress(WSS)andwallpressuregradient(WPG)inidealizedandimage-basedrightcoronaryartery(RCA)modelswithside-branches,inordertoexploretheeffectsofcurvatureandbifurcationonblood owcharacteristicsanditshemodynamicvariables.Uponestablishingandimplementingthisparametricanalysisframework,itisfoundthattherelativelylowerwallshearstressandWPGregionsatthecurvatureandbranchbifurcationsitesofarteriescoincidewiththeplaquespronepointsofthethreeinvestigatedimage-basedarteries,totherebycon rmthecorrelationofthe uidmechanicalpropertieswiththearterialgeometryvariationinconsistencewiththedatafromexistingliteratures.Moreover,theaverageWSSandPressuredrop(frominlettooutlet)aresigni cantlyincreasedwiththemorecomplexgeometryofrealisticarteriesincomparisonwithidealizedarterialmodels.Itcanhencebeconcludedthatthegeometryofcurvatureandangulationofthesidebrancheshasasigni canteffectontheWSSandWPGinhemodynamicsanalysisofRCAsanditscorrelationwithatheroscleroticlesions.

&2015ElsevierLtd.Allrightsreserved.

1.Introduction

Thedistributionofwallshearstress(WSS)incoronaryarteriesisasigni cantcontributoryfactorfortheonsetofcoronarydisease.Recently,therehavebeensomedebatesastowhatdegreeofWSSorlargeWSSgradientsiscontributorytotheonsetofplaqueformationandruptureatthesametime.VariousstudieshavegoneintoexplaininghowregionsaredifferentiatedintovaryingdegreesofWSSandlinktheirimplicationstovesselnarrowing[3,32,14,36].ItiswidelyavailableintheseliteraturesthatatheroscleroticplaquesarelocatedatlowWSSandwall

Correspondingauthor.

Correspondingkeyauthorat:SchoolofComputerScienceandSoftwareEngineering,TheUniversityofWesternAustralia,35StirlingHighway,Crawley6009,WA,Australia.Tel.:þ61864883100;fax:þ61864881089.

E-mailaddresses:jh.wu@http://doc.guandang.net(J.Wu),kelvin.wong@uwa.edu.au(K.K.L.Wong).

nn

n

pressuregradient(WPG)regions,anditisacceptedthatlocalhemodynamicforcesplayanimportantroleintheformationandruptureofatheroscleroticplaques.DynamiccurvilineararterialgeometrieshavebeendemonstratedtostronglyaffectWSSbasedoncoronaryarterybifurcationmodels[41,13,28].However,adetailedquanti cationoftheWSSvariationswiththisarterialcurvaturehasnotbeenstudiedwithsuf cientanalyticalandcomputationalsophistication.

ThepurposeofourstudyishencetocomputationallyanalyzetheWSSandWPGvariationsinidealizedandrealisticrightcoronaryartery(RCA)models,andfocuson:(a)determiningthedistributionmapofWSSandWPGinRCAs,bytakingintoaccounttheircurvaturesandbifurcations;(b)evaluatingthevariationsofaverageWSS(de nedasonthevesselwallandpressuredrop(ΔP)acrossthearterialinletandoutlet.Despitethewell-knownrelationshipofarterialcurvaturewithWSSandΔP,anelaborateandconciseparametricstudyof‘howthegeometricalvariationofthecurvilineararteriesanditsbranchesaffectsthe

http://doc.guandang.net/10.1016/http://doc.guandang.netpbiomed.2015.06.0090010-4825/&2015ElsevierLtd.Allrights

reserved.

Numerical Simulation of Flow in Curved CoronaryArteries with Progressive Amounts of StenosisUsing Fluid-Structure Interaction Modelling

118G.Liuetal./ComputersinBiologyandMedicine64(2015)117–126

blood owandhemodynamicproperties’hasnotbeperformedpreviouslytothebestofourknowledge.Quantitativehemody-namicanalysisandthe owpropertiesofspeci cally-de nedregions,suchastheinnerandouterwallsofthetrunk,arepresentedhereintoenableadetailedunderstandingoftherelationshipbetween(i)arterialtrunkcurvature,angleofbranch-ing,aswellascurvatureofthebranches,and(ii)the uidmechanicsofbloodthroughit.

Computational uiddynamics(CFD)isnowwidelyemployedinthehemodynamicanalysisofaorta,carotidandcoronaryarteriesundersimulatedphysiologicalandpathologicalconditions[37,39].Inourstudy,wehave(i)demonstratedthattherearesigni cantdifferencesinthemagnitudesofWSSandWPGinarterieswithdifferentcurvatureandangulation,and(ii)deter-minedthesehemodynamicpropertiesinrightcoronaryarteriessitesofhighcurvatureandbranchbifurcationlocationsassociatedwithoccurrenceofatheroscleroticplaques.Theseresultsrevealthatcurvatureandbranch owshaveabigin uenceonthedistributionsofWSSandWPGinthecoronaryarterialtrunk.Afterthisstudy,weintendtoutilizethese ndingsandadoptamethodologyforcarryingoutpre-surgicalanalysisofplaque-occludedarteries.Itallowsustoplanthesurgicaldesignsofcoronaryarterialbypassgrafts(CABGs)soastominimizetheadversehemodynamic owpatternsandthevaluesofthehem …… 此处隐藏：39089字，全部文档内容请下载后查看。喜欢就下载吧 ……