除顫起搏器的臨床應(yīng)用ContentsICDHistoryBasicfunctionsofdefibSensing,detectionandtherapiesICDindications—whogetsoneornotImplantprocedure—howdowetestthedevice.HistoryofICDsInternaldefibrillatorLate1940’sto1950’sUnitshownisfromtheearly1960’s1985-FirstapprovedICDBulky,heavyShort-lived(18m)AbdominalimplantThoracotomyrequiredNon-programmableLimitedtherapyoptionsVentakisatrademarkofCardiacPacemakers,Inc.ThenextmilestoneforICDsPectoralimplantsapprovedbytheFDAin1995MorecomfortableforpatientsFasterimplantsSmallerbutjustaspowerfulasolderdevices“ActiveCan”TechnologyTraditional

SystemRV-Can“DualChamber”ICDsIntroducedin1997CombinedualchamberpacingwithventriculararrhythmiadetectionandtherapyAbilitytosenseatrialactivityduringarrhythmiasSVTDiscrimination:Theabilitytowithholdtherapyfornon-lethalarrhythmiasBasicFunctionsofICDAutomaticallydetectandtreatVentricularTachycardia(VT)Antitachycardiapacing(ATP)CardioversionAutomaticallydetectandtreatVentricularFibrillation(VF)DefibrillationBradypacingVVI,VVIR,DDDRHowitworksSensingDetectionTherapyThreeZoneDetectionVTFVTVFVTDetectionVentricularsensitivityTachydetectioninterval(TDI)VTinitialNIDVTredetectNID

VF FVT VTDetectionStatus: ON OFF ONInterval(ms): 320 400InitialNID: 12/16 12Sensitivity(mV): 0.3VTCounterValue: 1 2 3 4 5 6 7 8 9 10 11 12200msVSVSVSVSVSTSTSTSTSTSTSTSTSTSTSTSTDVFDetectionVentricularsensitivityFibrillationdetectioninterval(FDI)VFinitialNIDVFredetectionNIDFVTDetectionviaVTCounter

VF FVT VTDetectionStatus: ON ON ONInterval(ms): 320 380 500InitialNID: 12/16 12121110987654321LOOKBACKWINDOW

(8INTERVALSBEFORENID)V

SV

SV

ST

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ST

ST

ST

ST

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F?T

ST

F?VFCounter:IncreasedVTDetectionSpecificitySinusTachycardiaAtrialTachycardiaAtrialFlutterAtrialFibrillationMorphologyXXXXOnsetXStability

XTherapiesATPBurstRampRamp+CardioversionDefibrillation

Ramp

Ramp+ICDIndications,whogetsoneornotClassI:Evidence/generalagreementregardingbenefit,usefulness,andeffectiveness ClassII:Conflictingevidence/divergenceofopinionregardingusefulness/effectivenessIIa:Weightofevidence/opinioninfavorofusefulness/effectivenessIIb:Usefulness/effectivenesslesswellestablishedbyevidence/opinion.ClassIII:Evidence/generalagreementregardinglackofusefulness/effectiveness(harmfulinsomecases)GregoratosG.JAmCollCardiol.1998;31:1175-1209.1998ClassIIIndications1. CardiacarrestpresumedtobeduetoVFwhenEPtestingisprecludedbyothermedicalconditions.

(Levelofevidence:C)2. Severesymptomsattributabletosustainedventriculartachyarrhythmiaswhileawaitingcardiactransplantation.(Levelofevidence:C)3. Familialorinheritedconditionswithahighriskforlife-threateningventriculartachyarrhythmiassuchaslongQTsyndromeorhypertrophiccardiomyopathy.(Levelofevidence:B)GregoratosG.JAmCollCardiol.1998;31:1175-1209.1998ClassIIIndications(cont.)4. NonsustainedVTwithcoronaryarterydisease,priorMI,andLVdysfunction,andinduciblesustainedVTorVFatEPstudy.(Levelofevidence:B)5. RecurrentsyncopeofundeterminedetiologyinthepresenceofventriculardysfunctionandinducibleventriculararrhythmiasatEPstudy,whenothercausesofsyncopehavebeenexcluded.

(Levelofevidence:C)GregoratosG.JAmCollCardiol.1998;31:1175-1209.ImplantProcedureInsertionofdefibleadsTestpacingparametersthroughanalyzerofP/Rwave,leadimpedances,andpacingthresholdConnectdefibleadswithdefibboxTestpacingimpedance