（参考课件）心源性脑栓塞.ppt

心源性脑栓塞,1,病历特点,中年男性，反复发作渐进性病程；既往高血压史，夹层动脉瘤及主动脉瓣关闭不全换瓣术后3年，口服抗凝药不规范。近2年多次脑梗塞史。发病表现为反复发作的神经功能缺损，渐进性的神经功能缺损。查体主要表现为言语表达障碍，构音含混，右面部麻木及右肢轻偏瘫，及右侧同向偏盲。辅助检查：凝血象（INR）偏低；CT：脑内多发梗塞,2,定位诊断,双侧颈内动脉系统，左侧著椎基底动脉系统？,3,定性诊断,心源性栓塞主动脉机械瓣膜组织栓子脱落,4,AorticDissection,Anatomy,PhysiologyandPrinciplesofTherapy,5,History,1555Vesaliusdiagnosedapulsatingtumornearthevertebraeinapatientsbackandcalledit“adilatationoftheaorta”18261826Laennecintroducedthetermdissectinganeurysm1800ssurgerywasperformedontheentitybyJohnHunter,AstleyCooperandothersevenbeforetheeraofgeneralanesthesiaEarlyoperationsweredesignedtoproducedistalinternalfenestrationtocausedownstreamdecompressionoftheaorta.,6,History,1951LamandAramintroducedhomograftsforrepairofdescendingthoracicaneurysms1953CooleyandDeBakeyusedartificialgraftsforrepair1953Bahnsonintroducedaneurysmorrhaphy1957cardiopulmonarybypassbecameavailable,7,Definition,TrueaneurysmlocalizedenlargementoftheaortacontainedbyallthelayersoftheaorticwallFalseaneurysmenlargementcontainedbytheaorticadventitiaandperiaorticfibroustissue.,8,9,10,Definition,AorticdissectionSuddencatastrophiceventinwhichatearintheintimaallowsbloodtoescapefromthetruelumenoftheaortarapidlyseparatingtheinnerfromtheouterlayerofthemediaColumnofbloodisdrivenbytheforceoftheleftventricularsystolicpressurewhichstripstheintimafromtheadventitia,11,Definition,Acutelessthan14daysoldChickenortheegg?Hemorrhageinthemediacausesruptureoftheintimaordissectinghematomainanintimaltear.,12,CausesofAneurysm,MedialdegenerationandlocaldilatationAtherosclerosisSyphilis(ascendingonly)Bacterialinfections(mycotic)CongenitalabnormalitiesTraumaAnnuloaorticectasia,13,CausesofDissection,InherentweaknessoftheaorticwallHypertension70-90%PregnancyIatrogenicBicuspidaorticvalveandcoarctationClosedchesttrauma,14,Pathophysiology,LawofLaplace:Asasphereincreasesinsize,thewalltensionofthesphereincreasesWeakenedwallDilatationExpansionwithpressure-relatedsymptomsRupture,15,NaturalHistory,NotwelldocumentedSigns,symptomsandprognosisrelatedtothesizeoftheaneurysmThoracicaneurysmslargerthan6cmaremorepronetorupturethanthesmallerones5yearsurvivalforsymptomaticaneurysmsis27%whereas58%withasymptomaticonessurvivedthesameperiodoftime.Ruptureisthemostcommoncauseofdeath,16,NaturalHistory,ManypatientswithdissectiondieacutelyduetocardiactamponadeordissectionoftheLAD8%ofascendingrupturessurvivewithouttreatment75%survivedescendingdissection,17,Classification,TypeI-BeginsattheaorticvalveandmayproceedtoandincludetheabdominalaortaTypeIIBeginsdistaltotheleftsubclavianarteryandcanencompasstheentireaortatotheiliacarteries,18,19,20,21,AnatomicalConsiderations,22,Pathoanatomy,Dissectionoftheascendingaortaariseswithinseveralcentimetersoftheaorticvalve66%DissectionofthedescendingaortaoccurjustbeyondtheleftsubclavianarteryattheligamentumarteriosumSmallpercentageoccuratthetransversearchordescendingaorta,23,Pathophysiology,Afterdissectionintothemedia,bloodrushesintothedissectedareaNecrosisoftheaorticwallthendevelopsseveraldaysaftertheeventobservedin62%ofcasesComplicationsincludeaorticrupture,obstructionandocclusionofaorticbranches,24,25,ClinicalSignsandSymptoms,26,Demographics,Malesfemales3:1SixthorseventhdecadeoflifePatientswithascendingdissectionareabouttenyearsyoungeratpresentationthanthosewithdescendingdissection,27,Symptoms,Sudden,severechestpaintearingsensationintheanteriorchestradiatingtothearmsortobetweenthescapulaeMayhavesyncope,neurologicsigns,weakness,hypotension.,28,PhysicalFindings,ParalysisMuffledhearttonesNewonsetaorticinsufficiencymurmurUnequalbloodpressureandpulsesintheextremitiesJugularvenousdistentiontamponadeAbdominalpainacuteAcutehypertensionandanuria,29,Diagnosis,Plainchestradiographwidenedmediastinum,pleuraleffusionElectrocardiogrammayresembleacutemyocardialinfarctionparticularlyiftheLADisaffectedCTscanidentifiestheproblembutdoesnotprovidearoadmapAngiographygoldstandardTransesophagealechocardiography,30,31,32,33,34,Therapy,35,AscendingDissection,SurgicalemergencyCanonlybetreatedbyoperationMayormaynotrequireaorticvalvereplacementand/orcoronarybypasssurgerydependingontheprogressionofthedissectionMortalityabout20%dependingonothermedicalproblemsandthepresenceofneurologicalsymptoms,36,DescendingDissection,TherapycontroversialIfrupturepresentoperationistheonlyalternativeIntheabsenceofrupture,medicallytreatedpatientsdobetterthanthoseundergoingoperationduetocomorbidities,37,GoalofOperativeTherapy,ObliterationofthesiteoftheintimaltearandthefalselumenReapproximationofthedissectedaortaRepairofaorticvalveorreplacementwithvalveconduitPerformbypassgraftingasneeded,38,ConductoftheOperation,AppropriatepreoperativeassessmentGeneralanesthesiaCardiopulmonarybypassAscendingdissectionprofoundhypothermiawithcirculatoryarrestDescendingdissectionbypasswith/withoutarrest,39,40,41,42,GoalofMedicalTherapyinDescendingDissection,ReducetheforceofthebloodtraversingtheweakenedaorticwallDecreasecardiaccontractileforcebetablockadeIncreaserunoff-vasodilators,43,RepairofDescendi