Tc99UsedInCardiacHeartImagingTc99UsedInCardiacHeartIma1OutlineBackgroundofNuclearCardiologyElementsUsedinHeartImagingImagingTechniquesHeartImagesOutlineBackgroundofNuclearC2BackgroundofNuclearCardiologyNuclearcardiologyimagingprocedureshavevastlydevelopedoverthepast25yearswithadvantagesandtreatmentsofheartdisease.Myocardialperfusionimaging(MPI)offersahighdegreeofaccuracyinthedetection,diagnosis,andprognosisofcoronaryarterydisease.MPIisthemostcommonprocedureindeterminingheartdisease.BackgroundofNuclearCardiolo3InstrumentationofNuclearImagingUsesradiopharmaceuticalsthatlocalizetoatargetorgan.Inthecaseofcardiology,imagingagentsareusedthatwillflowtoandaccumulateinthemyocardiumoftheheart.Nuclearheartimagingisperformedwithanuclearcamera.TheheartimagingprocessisreferredtoasSinglePhotonEmissionComputerizedTomography(SPECT).Tc99isthemostcommonradionuclideusedtodayincardiacimaging.InstrumentationofNuclearIma4NuclearCardiologyCameraNuclearCardiologyCamera5TheThalliusIon(201Tl)Thefirstuseofradiopharmaceuticalsincardiacheartimagingbeganin1975inwhichthethalliusionwasused.TheThalliusIon(201Tl)Thefi6ProblemswithThalliumLimitedSensitivity/Accuracy80%ShorthalflifeDoesnotstayboundtotissueImagesmustbetakenquicklyduetoredistribution.Difficulttoconcentratetargetorgan.

ProblemswithThalliumLimited7Technetium75%ofproceduresusestechnetium99indiagnosingcardiacdiseases.Half-lifeof6hours140KeVgammarayemissionHighenoughinenergytopenetratethebody’stissues,butlowenoughnottoharmthebody.Twotypesoftechnetiumtobediscussed 1)Tc99TBI2)Tc99SestamibiTechnetium75%ofprocedures8Technetium99TBI1stTechniciumcompoundintroducedtonuclearcardiacimagingStructuralNameHexakis-(t-butylisonitrile)-Technetium(I)SixCoordinateIsonitrileOctahedralgeometry+1oxidationstateTechnetium99TBI1stTechniciu9StructureofTc99TBIStructureofTc99TBI10ProblemswithTc99TBIHighactivityinotherpartsofthebody.RedistributionProblemswithTc99TBIHighact11Tc99Sestamibi(MIBI)Derived

fromTc99TBIComposedoffunctionalgroupsthatgiveclearancefromnon-targetorgansSixcoordinateOctahedralgeometryGreaterhydrophilicitythanTcTBIduetoitsmethoxygroups.LypophillicTc99Sestamibi(MIBI)Derivedf12StructureofTc99SestamibiStructureofTc99Sestamibi13Tc99MIBITechniqueOneDayStressProtocolTwoDayStressProtocolDualIsotopeScanningGatingLVEF(LeftVentricleEjectionFraction)Tc99MIBITechniqueOneDayStr14OneDayStressProtocolOnedayConsistsofarestexamfollowedbyastressexaminthesameday.InjectionofTcMIBIisperformedafteraresttestandafterastresstest.1stinjectionisalowdose2ndinjectionisahigherdose(3Xtherestinjection)ProblemsNotaccurateinsomeinstancesOneDayStressProtocolOneday15TwoDayStressProtocolTwoDayConductedonlyiftheonedaytestwasunsuccessful.Reststudynotnecessaryifstresstestwasnormal.ProblemsSameaswiththeonedayTwoDayStressProtocolTwoDay16DualIsotopeScanningResttestwithThalliumstudyconductedondayoneThalliumredistributessoothertestingcanbeperformedStresstestwithTechnetiumstudyisconductedondaytwoDrawbacksDifferentresolutionmakesitdifficulttocompareheartimages.DualIsotopeScanningResttest17GatingMostpopularinnuclearheartimaging.ImprovesdiagnosticaccuracyofSPECTimaging.Sharper,clearerimagesthanothertechniques.Accessesregionalwallmotionandleftventricularejectionfraction.Providesinformationregardingmyocardialsystolicfunctionsandprognosis.Allowsanejectionfractiontobecalculated.GatingMostpopularinnuclear18LeftVentricleEjectionFractionsProvidesprognosticinformationfortheriskofheartdiseasesbyusingthegatedSPECT.Leftventricleiswheremostoftheheartfunctionismeasuredsinceitpumpsbloodthroughoutthebody.Measurestheamountofbloodthattheleftventriclepumpsoutperbeat.EFoflessthan40%areatriskofsomesortofcardiacevent.EFoflessthan30%areatriskforcardiacdeath.LeftVentricleEjectionFracti19WhattheimagesmeanThickened,brighterimagesonSPECTscansindicatesviablehearttissue.Thinnerimageindicatesthatthereispossiblescarringorinfarctionoftheheart.WhattheimagesmeanThickened,20NormalvsAbnormalHeartImageLeftImage-abnormalRightImage-normal

NormalvsAbnormalHeartImage21PrognosisUsingTcHeartImagingPositiveMIBIscansarenearly100%accurate.NegativeMIBIscansarejustasaccurate.PrognosisUsingTcHeartImagi22ConclusionTcMIBIisthebestradionuclearheartimagingagentusedtoday.Allowsmanyimagingtechniquestobeperformedthatarecriticalfordiagnosingheartdiseases.ConclusionTcMIBIisthebest23ReferencesJurisson,S.“CoordinationCompoundsinNuclearMedicine.”ChemicalReviews.1993,93,1137-1156.Holman,Sporn,Jones,etal.“MyocardialImagingwithTechnetium99CPI:InitialExperienceintheHuman”,TheJournalofNuclearMedicine.Angelberger,P.“Tc-99m(Tc-99m-TBI):optimizedsynthesis,radiochromatography,biodistribution,andpreliminarychemicalstudies.”“TechnetiumLabeledCardiacImaging.”/scottwilliamsmd2/nucmed/cardiovascular/Sestamibi.html“CardiacNuclearImaging.”/serv_nuclear.shtmlReferencesJurisson,S.“Coord24Tc99UsedInCardiacHeartImagingTc99UsedInCardiacHeartIma25OutlineBackgroundofNuclearCardiologyElementsUsedinHeartImagingImagingTechniquesHeartImagesOutlineBackgroundofNuclearC26BackgroundofNuclearCardiologyNuclearcardiologyimagingprocedureshavevastlydevelopedoverthepast25yearswithadvantagesandtreatmentsofheartdisease.Myocardialperfusionimaging(MPI)offersahighdegreeofaccuracyinthedetection,diagnosis,andprognosisofcoronaryarterydisease.MPIisthemostcommonprocedureindeterminingheartdisease.BackgroundofNuclearCardiolo27InstrumentationofNuclearImagingUsesradiopharmaceuticalsthatlocalizetoatargetorgan.Inthecaseofcardiology,imagingagentsareusedthatwillflowtoandaccumulateinthemyocardiumoftheheart.Nuclearheartimagingisperformedwithanuclearcamera.TheheartimagingprocessisreferredtoasSinglePhotonEmissionComputerizedTomography(SPECT).Tc99isthemostcommonradionuclideusedtodayincardiacimaging.InstrumentationofNuclearIma28NuclearCardiologyCameraNuclearCardiologyCamera29TheThalliusIon(201Tl)Thefirstuseofradiopharmaceuticalsincardiacheartimagingbeganin1975inwhichthethalliusionwasused.TheThalliusIon(201Tl)Thefi30ProblemswithThalliumLimitedSensitivity/Accuracy80%ShorthalflifeDoesnotstayboundtotissueImagesmustbetakenquicklyduetoredistribution.Difficulttoconcentratetargetorgan.

ProblemswithThalliumLimited31Technetium75%ofproceduresusestechnetium99indiagnosingcardiacdiseases.Half-lifeof6hours140KeVgammarayemissionHighenoughinenergytopenetratethebody’stissues,butlowenoughnottoharmthebody.Twotypesoftechnetiumtobediscussed 1)Tc99TBI2)Tc99SestamibiTechnetium75%ofprocedures32Technetium99TBI1stTechniciumcompoundintroducedtonuclearcardiacimagingStructuralNameHexakis-(t-butylisonitrile)-Technetium(I)SixCoordinateIsonitrileOctahedralgeometry+1oxidationstateTechnetium99TBI1stTechniciu33StructureofTc99TBIStructureofTc99TBI34ProblemswithTc99TBIHighactivityinotherpartsofthebody.RedistributionProblemswithTc99TBIHighact35Tc99Sestamibi(MIBI)Derived

fromTc99TBIComposedoffunctionalgroupsthatgiveclearancefromnon-targetorgansSixcoordinateOctahedralgeometryGreaterhydrophilicitythanTcTBIduetoitsmethoxygroups.LypophillicTc99Sestamibi(MIBI)Derivedf36StructureofTc99SestamibiStructureofTc99Sestamibi37Tc99MIBITechniqueOneDayStressProtocolTwoDayStressProtocolDualIsotopeScanningGatingLVEF(LeftVentricleEjectionFraction)Tc99MIBITechniqueOneDayStr38OneDayStressProtocolOnedayConsistsofarestexamfollowedbyastressexaminthesameday.InjectionofTcMIBIisperformedafteraresttestandafterastresstest.1stinjectionisalowdose2ndinjectionisahigherdose(3Xtherestinjection)ProblemsNotaccurateinsomeinstancesOneDayStressProtocolOneday39TwoDayStressProtocolTwoDayConductedonlyiftheonedaytestwasunsuccessful.Reststudynotnecessaryifstresstestwasnormal.ProblemsSameaswiththeonedayTwoDayStressProtocolTwoDay40DualIsotopeScanningResttestwithThalliumstudyconductedondayoneThalliumredistributessoothertestingcanbeperformedStresstestwithTechnetiumstudyisconductedondaytwoDrawbacksDifferentresolutionmakesitdifficulttocompareheartimages.DualIsotopeScanningResttest41GatingMostpopularinnuclearheartimaging.ImprovesdiagnosticaccuracyofSPECTimaging.Sharper,clearerimagesthanothertechniques.Accessesregionalwallmotionandleftventricularejectionfraction.Providesinformationregardingmyocardialsystolicfunctionsandprognosis.Allowsanejectionfractiontobecalculated.GatingMostpopularinnuclear42LeftVentricleEjectionFractionsProvidesprognosticinformationfortheriskofheartdiseasesbyusingthegatedSPECT.Leftventricleiswheremostoftheheartfunctionismeasuredsinceitpumpsbloodthroughoutthebody.Measurestheamountofbloodthattheleftventriclepumpsoutperbeat.EFoflessthan40%areatriskofsomesortofcardiacevent.EFoflessthan30%areatriskforcardiacdeath.LeftVentricleEjectionFracti43WhattheimagesmeanThickened,brighterimagesonSPECTscansindicatesviablehearttissue.Thinnerimageindi