血管内超声基础知识

血管内超声根底知识阜外医院钱杰南方会2021血管内超声根底知识一、血管内超声根底二、血管内超声和冠脉造影的关系三、主要适应症四、什么是VH南方会2021RotatingElementDriveShaftMulti-elementArrayTherearetwotypesofimagingsystems:Mechanical(rotatingtransducer)andElectronicArray南方会2021HighfrequencysoundwavesechooffvesselwallsandaresentbacktosystemSystemelectronicsprocessthesignal南方会2021Intimaldisease(plaque)isdenseandwillappear‘white’Mediaismadeofhomogeneoussmoothmusclecellsanddoesnotreflectultrasound(appearsdark)Adventitiahas‘sheets’ofcollagenthatreflectalotofultrasound(appearswhite)南方会2021南方会2021CalciumBrightechoes(brighterthantheadventitia)Obstructsthepenetrationofultrasound(acousticshadowing)onlytheleadingedgeisdetectedandthicknesscannotbedetermined.Resultsinreverberations-theoscillationofultrasoundbetweentransducerandcalciumcausingrepeating‘arcs’南方会202180°SuperficialDeepDeepCalciumisquantifiedbymeasuringthe“arc〞itencompassesCalciumisclassifiedbyitslocationwithintheplaqueSuperficialcalciumisclosertothelumenthantotheadventitiaDeepcalciumisclosertotheadventitiathantothelumen南方会2021FibroticPlaqueAsbrightorbrighterthantheadventitia(hyperechoic)MajorityofatheroscleroticlesionsarefibroticVerydense,fibrousplaquesmaycausesomuchacousticshadowingthattheycouldbemisclassifiedascalcified南方会2021SoftPlaqueNotasbrightastheadventitia(hypoechoic)“Soft〞referstothelowechogenicity,generallyduetohighlipidcontentinamostlycellularlesion.Reducedechodensitymayalsobedueto:necroticzonewithinplaqueintramuralhemorrhagethrombus南方会2021VulnerablePlaqueFibrousCapLipidCore南方会2021MixedPlaque南方会2021014mmExampleofThrombus南方会2021BasicMeasurements(I)Externalelasticmembrane(EEM)crosssectionalarea(CSA)=totalarterialCSA=‘media’areatracingtheboundarybetweenthedarkmediaandthe

brightadventitia(i.e.,theapparentouteredgeofthemediastripe)LumenCSAMaxandminlumendiametersStentCSAMaxandminstentdiametersPlaque+media(P+M)CSA=EEM-LumenCSAinnon-stentedlesions=EEM-stentCSAinstentedlesionsIntimalhyperplasiaCSA=Stent-LumenCSA南方会2021BasicMeasurements(II)Eccentricity=maximum/minimumP+MthicknessPlaqueBurden(=cross-sectionalnarrowingor%plaquearea)=P+M/EEMCSARemodelingIndex=Lesion/ReferenceEEMCSAAreaStenosis=(Reference-Lesion)/ReferenceLumenCSAArcofcalciumLesionlengthsmeasuredusingmotorizedtransducerpullback,ideallyat0.5mm/sec南方会2021Non-stentedarteryEEMGuidewiresIVUScatheterPlaque+mediaLumen南方会2021StentedArteryEEMLumenStentGuidewireIVUScatheterPlaque+mediaIntimalhyperplasia南方会2021ProximalReferenceLesionSiteDistalReferenceEEMLumenP+MMaxP+MThicknessMinP+MThicknessCa++南方会202103mm12mmProximalReferenceLesionSiteDistalReferenceEEMCSA=20.4LumenCSA=9.7Maxlumendiam=3.7MLD=3.1P+MCSA=10.7Eccentricity=1.0/0.3Plaqueburden=0.52ArcofCa=60EEMCSA=21.6LumenCSA=4.5Maxlumendiam=32.8MLD=2.3P+MCSA=17.1Eccentricity=3.0/0.1Plaqueburden=0.79EEMCSA=13.3LumenCSA=8.9Maxlumendiam=3.6MLD=3.0P+MCSA=4.4Eccentricity=0.6/0.2Plaqueburden=0.33AverageReferenceEEMCSA=16.9RemodelingIndex=1.3AverageReferenceLumenCSA=9.3AreaStenosis=52%南方会2021In-StentRestenosisIn-stentintimalhyperplasia(IH)oftenappearswithaverylowechogenicityCouldbelessechogenicthanthebloodspeckleAppropriatesystemsettingsarecriticaltovisualizeIH(donot“blackout〞center)南方会2021血管内超声根底知识一、血管内超声根底二、血管内超声和冠脉造影的关系三、主要适应症四、什么是VH南方会2021LimitationsofCoronaryAngiographyFocalDisease50%Lesion50%LesionDiffuseDiseaseAngiogramSilhouette南方会2021AngiographicallySilentDiseaseIn884nativecoronaryarteries,theplaqueburdenintheangiographically“normal〞referencesegmentwas51±13%MintzGS,etal.JAmCollCardiol1995;25:1479-1485南方会2021CoronaryRemodelingHypothesisCompenatoryExpansion

MaintainsConsistantLumenExpansion

Overcome:LumenNarrowsNormalVesselMinimalCADModerateCADSevereCAD南方会2021ProximalreferenceLesionDistalreferenceIntermediateremodelingNegativeremodelingPositiveremodelingNishioka.

JACC1996;27:1571-1576DicotomousClassificationofRemodeling南方会2021IrregularPlaque/IrregularLumenACross-sectionRAOViewLAOViewBC南方会2021IVUSEEMCSA=22.7mm2LumenCSA=16.6mm2Meanlumendiameter=4.6mmQCA9FguidingcatheterReferencediameter=3.12mm南方会2021血管内超声根底知识一、血管内超声根底二、血管内超声和冠脉造影的关系三、主要适应症四、什么是VH南方会2021ValidationofIVUSAssessmentofIschemiaProducingStenosis(DopplerFloWireandSPECT)IVUSMLA4.0mm2IVUSMLA<4.0mm2CFR<2.0227CFR2.0394Diagnosticaccuracy=92%.Abizaidetal,AJC1998;82:42-8IVUSMLA4.0mm2IVUSMLA<4.0mm2+Spect442-Spect201Diagnosticaccuracy=93%.Nishiokaetal,JACC1999;33:1870-8南方会2021IVUSCriteriafora‘Significant’StenosisBasedonthestudiescomparingIVUStoflowwire,pressurewire,orSPECTthalliumandbasedonstudieswithclinicaloutcome-mostfeelthatalumenarealessthan4.0mm2inaproximalepicardialarteryexcludingtheLeftMainisaflowlimitingstenosis南方会2021PoorinterobserveragreementintheangiographicassessmentofLMCAstenosisintheCASSstudyII(Cameronetal.Circulation1983;68:484-489)FivegradesofLMseverity1: 0-24%DS2: 25-49%DS3: 50-74%DS4: 75-89%DS5: 90-100%DS#ofgradesofdifferenceinassessmentofLMseverity

0: nodifference+1or-1: 1gradedifference+2or-2: 2gradesofdifference+3or-3: 3gradesofdifference+4or-4: 4gradesofdifferenceClinicalsitevs

QualitycontrolClinicalsitevs

StudyGroupStudyGroupvsQualitycontrol南方会2021ReferenceLesion10mmLumenCSA=18.3mm2Lumendiameter=5.0mmLumenCSA=3.6mm2Lumendiameter=1.3mmLumenCSA=11.9mm2Lumendiameter=3.5mmPatientwithnormalostialLMCAwhopreviouslyunderwentCABGforpresumedLMCAdiseasePatientwithsevere,butunrecognized,distalLMCAstenosiswhowasreferredforPTCAofLAD南方会2021SuggestedIVUSCriteriafora‘Significant’LMCAStenosisMostIVUSLMCAstudiesshoweitherinsignificantdiseaseorcriticaldisease,onlyaminorityrequirecarefulquantificationLumenCSA<6.0mm2orMLD<3.0mmaresuggestedcriteriaforasignificantLMCAstenosisThesumofthelumenareasofthetwodaughtervessels(LADandLCX,eachofwhichshouldbe4.0mm2)=150%oftheparent(LM)ThesecorrelatedwithanabnormalFFR

(JastietalCirculation2004;110:2831-6)南方会2021UnusualLesions:IVUSClassificationofAngiographicAneurysmsOf77angiographicaneurysms21(27%)trueaneurysm3(4%)pseudoaneurysm12(16%)complexplaquesorunhealeddissections41(53%)normalsegmentadjacenttooneormorestenosesTrue

AneurysmPSAComplex

PlaqueNormalSitewith

AdjacentStenosesNopriorPCI100626PriorPCI113615(Maeharaetal.AmJCardiol2001;88:365-70)南方会2021ProximalDistalLesion5.5mm

MaxLD=3.5mm

MaxLD=3.3mm6mmStentsizingusingIVUS南方会2021Thehighpredictivevalue(90%)fortheminimumstentCSAinCypherstentssuggeststhatmostcausesofCypherstentfailurewillbe“mechanical〞

01020304050607080901003.54.04.55.56.06.57.07.58.08.5F/UMLA>4.0mm2(%)Cypher5.0**sensitivityspecificity01020304050607080901003.54.04.55.05.56.07.07.58.08.5F/UMLA>4.0mm2(%)BareMetalStents6.5*Minimumstentarea(mm2)Minimumstentarea(mm2)(Sonodaetal.JAmCollCardiol2004;43:1959-63)*predictivevalue=56%**predictivevalue=90%南方会2021Predictorsofangiographicrestenosisin550ptswith670nativearterylesionstreatedwithCypherstents0204060801000204060801003.54.04.55.05.56.06.57.07.5Angiographicrestenosis(%)Angiographicrestenosis(%)IVUSMSA(mm2)10152025303540455560657075IVUStotalstentlength(mm)<5.5mm2≥5.5mm2≤40mm2.4%0.4%>40mm17.7%8.6%(Hongetal.unpublished)南方会2021ComparisonofIVUS-measuredminimumstentdiameter(MSD)andminimumstentarea(MSA)withthepredictedmeasurementsfromCordis(Cypherinyellow,n=133)andBSC(Taxusinred,n=67).DESachieveanaverageofonly75%ofthepredictedMSD(66%ofMSA)IVUSMeasuredMSA(mm2)PredictedMSA(mm2)IVUSMeasu