心電專業(yè)知識(shí)講座

RightAtriumPulmonaryArteryVenacavaAortaPulmonarycapillaryRightVentricleLeftatriumLeftventriclePulmonaryveinSystemiccapillaryThecardiovascularsystemconsistsoftheheartandbloodvessels心電專業(yè)知識(shí)講座第1頁(yè)心電專業(yè)知識(shí)講座第2頁(yè)心電專業(yè)知識(shí)講座第3頁(yè)

TissuefluidcirculationBlood

circulationLymphcirculation

(Power)Cerebralfluidcirculation心電專業(yè)知識(shí)講座第4頁(yè)人體淋巴系統(tǒng)心電專業(yè)知識(shí)講座第5頁(yè)人體腦室系統(tǒng)心電專業(yè)知識(shí)講座第6頁(yè)人體腦脊液循環(huán)心電專業(yè)知識(shí)講座第7頁(yè)

Thevalvesensureone-wayflowofthebloodinthecardiovascularsystemAVvalvesArterialvalves

VenousvalvesLymphaticvalvesBicuspidvalve(Mitralvalve)TricuspidvalveAortasemilunarvalvePulmonarysemilunarvalve心電專業(yè)知識(shí)講座第8頁(yè)ThefunctionofcirculatorysystemTransportsmaterialsthroughoutthebody

Nutrients,water,gases(O2,CO2),hormones,etcKeepshomeostasisofinternalenvironmentRegulatesbodytemperatureEndocrines

atrialdiureticpeptide,vascularactivesubstances心電專業(yè)知識(shí)講座第9頁(yè)CardiacPhysiologyExcitation&conduction（Electricalactivity）Pumpingfunction(mechanicactivity）心電專業(yè)知識(shí)講座第10頁(yè)Chapter9

CardiacElectrophysiology心電專業(yè)知識(shí)講座第11頁(yè)

TheimportanceofcardiacEP1.Basisofcardiaccontractionandpumpingactivity

2.Targetofdrugs3.Arrhythmia:diagnosis,treatment4.Research心電專業(yè)知識(shí)講座第12頁(yè)Section1

Theelectricalactivityof

thecardiomyocyte心電專業(yè)知識(shí)講座第13頁(yè)Transmembranepotential

ofthecardiomyocyteRestingpotential:varieswithdifferentcellsMaximaldiastolicpotential:shownonlyincellswithautorhythmicity心電專業(yè)知識(shí)講座第14頁(yè)TypesofthecardiomyocytesFastresponsecells:

1.Contractile(working)cells:ventricularmyocytesatrialmyocytes2.Autorhythmiccells:Hisbundle,PurkinjefibersInternodalpathwaysSlowresponsecells:1.Autorhythmiccells:

pacemakercellsinsinusnode,atrial-nodalzoneandnodal-HiszoneoftheAVnode2.Non-autorhythmiccells:cellsinAVnodalzone心電專業(yè)知識(shí)講座第15頁(yè)心電專業(yè)知識(shí)講座第16頁(yè)心電專業(yè)知識(shí)講座第17頁(yè)心電專業(yè)知識(shí)講座第18頁(yè)心電專業(yè)知識(shí)講座第19頁(yè)atrial-nodalzonenodalzonenodal-HiszoneHisbundleinternodalpathwaysAVnodeThestructureofAVnode心電專業(yè)知識(shí)講座第20頁(yè)心電專業(yè)知識(shí)講座第21頁(yè)心電專業(yè)知識(shí)講座第22頁(yè)心房肌希氏束浦氏纖維心室肌竇房結(jié)房室結(jié)心電專業(yè)知識(shí)講座第23頁(yè)心電專業(yè)知識(shí)講座第24頁(yè)1.Transmembranepotentialofthe

cardiacworking(contractile)cellsRestingpotential:

80

90mV,IK1channel(Kirchannel)Actionpotential:fastresponse,4phases心電專業(yè)知識(shí)講座第25頁(yè)APofatrialmyocyteAPofventricularmyocyte心電專業(yè)知識(shí)講座第26頁(yè)心電專業(yè)知識(shí)講座第27頁(yè)IonicbasisoftheAPofcardiaccontractilecellsPhase0(depolarizingphase):

INaPhase1(fastrepolarizingphase1):

ItoPhase2(plateauphase):IK,ICalPhase3(fastrepolarizingphase2)

:

IK,IK1Phase4(restingpotential):

IK1,Na+pump,etc心電專業(yè)知識(shí)講座第28頁(yè)心電專業(yè)知識(shí)講座第29頁(yè)心電專業(yè)知識(shí)講座第30頁(yè)心電專業(yè)知識(shí)講座第31頁(yè)心電專業(yè)知識(shí)講座第32頁(yè)Figure9-6ICalinventricularcell

Figure9-7IKrandIKsindogventricularcellIKrIKs心電專業(yè)知識(shí)講座第33頁(yè)心電專業(yè)知識(shí)講座第34頁(yè)心電專業(yè)知識(shí)講座第35頁(yè)2.DiastolicdepolarizationincardiacautorhythmiccellsPurkinjefiber:If,IK

Pcellinthesinusnode:If,ICaT,IKr

心電專業(yè)知識(shí)講座第36頁(yè)IonicbasisoftheAPofPurkinjefibersPhases0-3:similarwithcontractilecellPhase4(diastolicdepolarization):

If,IKDifferentnamesofIf:Ih

(hyperpolarizationactivatedcationchannel)PacemakercurrentIonicbasisofIf:Na+K+心電專業(yè)知識(shí)講座第37頁(yè)心電專業(yè)知識(shí)講座第38頁(yè)IonicbasisofthepacemakercellinsinusnodePhases0:ICalPhase3:IKPhase4:If,ICaT心電專業(yè)知識(shí)講座第39頁(yè)ArightwardshiftofthecurvemeansagreaterIfatthesamemembranepotential心電專業(yè)知識(shí)講座第40頁(yè)EarlyafterdepolarizationDelayedafterdepolarization心電專業(yè)知識(shí)講座第41頁(yè)Section2

Theelectricalcharacteristics

ofthecardiomyocyte心電專業(yè)知識(shí)講座第42頁(yè)P(yáng)hysiologicalcharacteristicsofcardiomyocyteExcitability（興奮性）Conductivity（傳導(dǎo)性）Autothythmicity(orpacemakeractivity)（自律性）Contractility（收縮性）心電專業(yè)知識(shí)講座第43頁(yè)ExcitabilityFactorsthatdeterminethe

excitability:Na+(orCa2+)channelproperties:

restingactivationinactivation

excitableexcitatednon-excitableARP,ERP(2)Thedistancebetweenrestingpotential(maximaldiastolicpotential)andthresholdpotential心電專業(yè)知識(shí)講座第44頁(yè)心電專業(yè)知識(shí)講座第45頁(yè)P(yáng)eriodicchangesoftheexcitabilityofLVcardiomyocyteafterexcitation

absoluterefractoryperiod(ARP)(0-55mV)effectiverefractoryperiod(ERP)(0-60mV)relativerefractoryperiod(RRP)(60-80mV)supranormalperiod(SNP)(80-90mV)Normalexcitability(90mV)心電專業(yè)知識(shí)講座第46頁(yè)心電專業(yè)知識(shí)講座第47頁(yè)P(yáng)ostrepolarizationrefractoriness

1.Normal:slowresponsecell,therecoveryofICalisslow,suchthatthemembraneisstillrefractoryafterfullrepolarization.2.Abnormal:myocardialinfarction/reperfusion心電專業(yè)知識(shí)講座第48頁(yè)P(yáng)VCCompensatorypause心電專業(yè)知識(shí)講座第49頁(yè)Factorsthataffecttheexcitability

Ions:

[K+]o:slighthigh[K+]oincreasesexcitabiltyserioushigh[K+]odecreasesexcitabilty

low[K+]oincreasesexcitabilty[Ca2+]o:high[Ca2+]oslightlydecreasesexcitabiltyviaaffectingNa+channel

low[Ca2+]oincreasesexcitabiltypH:lowextracellularpH(acidosis)心電專業(yè)知識(shí)講座第50頁(yè)2.Autorhythmicity(自動(dòng)節(jié)律性）Sinusnodeisthedominantpacemakeroftheheart

Sinusrhythm（竇性節(jié)律）Latentpacemaker(潛在起搏點(diǎn)）Ectopicpacemaker（異位起搏點(diǎn)）Waysbywhichsinusnodecontrolstheheart:Capture(搶先占領(lǐng)）Overdrivesuppression(超速驅(qū)動(dòng)抑制）心電專業(yè)知識(shí)講座第51頁(yè)Factorsthataffecttheautorhythmicity:

VelocityofdiastolicdepolarizationMaximaldiastolicpotentialThresholdpotential心電專業(yè)知識(shí)講座第52頁(yè)Autonomicnervecontroloftheautorhythmicity:

SympatheticdischargeincreasestheautorhythmicityVagalnervedischargedecreasestheautorhythmicity心電專業(yè)知識(shí)講座第53頁(yè)Keypoint

Question:WhycardiocytehasaverylongAPD?Answer:Toguaranteethattheheartdoesnottetanize(強(qiáng)直收縮，痙攣）,butexcitesandcontractsperiodically.心電專業(yè)知識(shí)講座第54頁(yè)3.Conductivity(傳導(dǎo)性）Themyocardiumisafunctionalsyncytium(機(jī)能合胞體）,theexcitationcanconductdirectlybetweencardiaccells.心電專業(yè)知識(shí)講座第55頁(yè)心電專業(yè)知識(shí)講座第56頁(yè)心電專業(yè)知識(shí)講座第57頁(yè)Conductionpathways

1.TheconductionofexcitationintheatriumPreferentialpathway(inter-atrialpathway)Inter-atrialcontractilecellconduction心電專業(yè)知識(shí)講座第58頁(yè)心電專業(yè)知識(shí)講座第59頁(yè)A-Vblock1stdegree:A-VconductionslowingP-Rintervalprolongation

1:1conduction2nddegree:(1)PRintervalgradualprolongation,thenaQRSlost(2)2:1conduction,PRintervalmaynotnecessarilyprolong3rddegree:completeAVblock,AVdissociation

心電專業(yè)知識(shí)講座第60頁(yè)2.Theconductionofexcitationintheventricle心電專業(yè)知識(shí)講座第61頁(yè)Howtomeasurecardiacconduction?心電專業(yè)知識(shí)講座第62頁(yè)1.Electricalmapping(標(biāo)測(cè)技術(shù)）

Multi-electrodearray2.Opticalmapping

Voltage-sensitivedye心電專業(yè)知識(shí)講座第63頁(yè)ApexRVLVLADSockElectrodeArray(125bipolarelectrodes)2D3D心電專業(yè)知識(shí)講座第64頁(yè)RVLVApexEarlysiteIsochronalmap(GlobalEpicardium)ApexRVLVLADSockelectrodearrayGlobalepicardialmappingofVT心電專業(yè)知識(shí)講座第65頁(yè)3.2cm3.8cmPlagueElectrodeArray(480bipolarelectrodes)心電專業(yè)知識(shí)講座第66頁(yè)Dogheart心電專業(yè)知識(shí)講座第67頁(yè)ComputerizedElectricalMappingshowingthepropagationofcardiacactivationB(3882)C(3902)E(3942)A(3867)D(3917)F(fiberorientation)SeptumRVRVLV心電專業(yè)知識(shí)講座第68頁(yè)G(1342)A(1252)H(1432)B(1272)D(1297)E(1307)C(1292)I(fiberorientation)SeptumRVLVF(1322)Conductionblock,wavebreak,andtheinitiationofVFduringrapidpacing心電專業(yè)知識(shí)講座第69頁(yè)CardiacWedgePreparation心電專業(yè)知識(shí)講座第70頁(yè)MappingareaEpiEarlysiteOpticalMap

(TransmuralSection)

EndoOpticalmappingoftheoriginofventricularautomaticity心電專業(yè)知識(shí)講座第71頁(yè)a.0msb.3msc.8msd.11msPMendo1cmepie.21msf.51msg.71msh.91msxy300msxy心電專業(yè)知識(shí)講座第72頁(yè)Section3

SurfaceECG心電專業(yè)知識(shí)講座第73頁(yè)NormalhumanSurfaceECG心電專業(yè)知識(shí)講座第74頁(yè)心電專業(yè)知識(shí)講座第75頁(yè)P(yáng)wave:

Atrial(leftandright)activation

Amplitude:<0.25mV;Duration:0.08-0.11secP-Rinterval:

Atrialactivationtime+A-VconductiontimeDuration:0.12-0.20secQRScomplex:ventriculardepolarizationS-Tsegment:

alltheventricularcellsareactivated.upwardshift:downwardshift:Twave:ventricularrepolarizationTawave(atrialTwave):atrialrepolarizationmergedinQRSQ-Tinterval:ventricularactivationtime(depol+repol)Uwave:mechanismandsignificanceunkown心電專業(yè)知識(shí)講座第76頁(yè)HowsurfaceECGforms?心電專業(yè)知識(shí)講座第77頁(yè)ECGleadsBipolarlimbleads(Standardleads):measurethepotentialdifferencebetweentwopoints.

LeadI:leftarm(+)——rightarm(－)

LeadII:leftleg(+)——rightarm(－)

LeadIII:leftleg(+)——leftarm(－)心電專業(yè)知識(shí)講座第78頁(yè)IfthethreelimbsofEinthoven‘striangle(assumedtobeequilateral)arebrokenapart,collapsed,andsuperimposedovertheheart,thenthepositiveelectrodeforleadIissaidtobeatzerodegreesrelativetotheheart(alongthehorizontalaxis)(seefigurebelow).

Similarly,thepositiveelectrodeforleadIIwillbe+60orelativetotheheart,andthepositiveelectrodeforleadIIIwillbe+120orelativetotheheart.

Thisnewconstructionoftheelectricalaxisiscalledtheaxialreferencesystem.

Withthissystem,awaveofdepolarizationtravelingat+60oproducesthegreatestpositivedeflectioninleadII.

Awaveofdepolarizationoriented+90orelativetotheheartproducesequallypositivedeflectionsinbothleadIIandIII.

Inthislatterexample,leadIshowsnonetdeflectionbecausethewaveofdepolarizationisheadingperpendiculartothe0o,orleadI,axis.“愛氏三角”心電專業(yè)知識(shí)講座第79頁(yè)(2)Unipolarlimbleads

Thecombinationoftheelectrodesofleftarm,rightarmandleftlegshowroughlyazeropotential,thispointiscalled

centralreferencepoint(中心電端）Unipolarlimbleads(單極肢體導(dǎo)聯(lián)）：measurethetruepotentialofapointonthebodysurface,

include:

VR,VL,VF（Nomoreused）AugmentedLimbLeads(Unipolar)(加壓?jiǎn)螛O肢體導(dǎo)聯(lián)）:3resistancesareloaded,thecentralreferencepointis“really”zero.

aVR,aVL,aVF心電專業(yè)知識(shí)講座第80頁(yè)Theaxialreferencesystem

TheaVLleadisat-30orelativetotheleadIaxis;aVRisat-150oandaVFisat+90o.

ThesixlimbleadsoftheECGrecordelectricalactivityalongthefrontalplane(冠狀面)

relativetotheheart.

Usingtheaxialreferencesystemandthesesixleads,itissimpletodefinethedirectionofanelectricalvectoratanygiveninstantintime.

Ifawaveofdepolarizationisspreadingfromright-to-leftalongthe0oaxis,thenleadIwillshowthegreatestpositiveamplitude.

Ifawaveofdepolarizationismovingfromleft-to-rightat+150o,thenaVLwillshowthegreatestnegativedeflection,etc.心電專業(yè)知識(shí)講座第81頁(yè)(3)Chestleads(Unipolar):V1-V6Thesearesixpositiveelectrodesplacedonthesurfaceofthechestovertheheartinordertorecordelectricalactivityinaplaneperpendiculartothefrontalplane(figure).

Awaveofdepolarizationtravelingtowardaparticularelectrodeonthechestsurfacewillelicitapositivedeflection.

心電專業(yè)知識(shí)講座第82頁(yè)Cellpolarizesatrestingcondition,nopotentialdifferenceexitsbetweendifferentsitesCellisdepolarizing(activating),justlikeelectricdipole(電偶極子）movement.source

sink

Duringcelldepolarizing,Electrodeatthenegativesiderecordsadownwarddeflection,andanupwarddeflection,viceversa.MembranepolarizationhypothesisofECGinterpretation（ECG形成膜極化學(xué)說(shuō)）Duringcellrepolarizing,Thesourceisbehindthesink,theelectrodesrecorddeflectionsinoppositedirectionsvsdepolarization.心電專業(yè)知識(shí)講座第83頁(yè)

Thebodyactsasaconductoroftheelectricalcurrentsgeneratedbytheheart,itispossibletoplaceelectrodesonthebodysurfaceandmeasurecardiacpotentials.

Byconvention,awaveofdepolarizationheadingtowardthepositiveelectrodeisrecordedasapositivevoltage(upwarddeflectionintherecording).

VolumeConductorPrinciplesofECGInterpretation（ECG形成容積導(dǎo)體原理）CardiactissueatrestingstateCardiactissuepartiallyexcited心電專業(yè)知識(shí)講座第84頁(yè)心電專業(yè)知識(shí)講座第85頁(yè)

Whatisvolumeconductor?Ifyouputacell(電池）intothecenterofacontainerfilledwithsaltsolution,thesolutionwillbechargedandbecomeavolumeconductor.Thenearerapointawayfromthepositivepole,thehigherthepotentialis.Thepotentialatagivenpointcanbecalculatedbytheequation:

V=E(cos/r2)(V,voltage.E,electromotiveforce)ABr

V心電專業(yè)知識(shí)講座第86頁(yè)

Similarly,thebodyisavolumeconductor,theheartislikeanElectricdipole(電偶極子)duringactivation.itispossibletoplaceelectrodesonthebodysurfaceandmeasurecardiacpotentials.心電專業(yè)知識(shí)講座第87頁(yè)Vector(矢量，向量）isaphysicalvariancewhichshowsbothquantity(intensityorlength)anddirection,forexample,themechanicalforce,electricalcurrent,etc.Theparallelquadranglelawoftheresultant

(協(xié)力平行四邊形法則）Vectorcardiogram(向量心電圖，心電向量圖）depictschangesincurrentvectorlengthanddirectionatdifferenttimesduringthecardiaccycle.心電專業(yè)知識(shí)講座第88頁(yè)SequenceofventriculardepolarizationandQRScomplex心電專業(yè)知識(shí)講座第89頁(yè)Sequenceofmyocardialactivationandvectorring心電專業(yè)知識(shí)講座第90頁(yè)Keypoint:TheECGrecordedbyeachofthesixlimbleadsistheprojectionofthefrontalvectorringontherespectiveleadaxis.(六個(gè)肢體導(dǎo)聯(lián)所統(tǒng)計(jì)心電圖是額面向量環(huán)在各導(dǎo)聯(lián)上投影)心電專業(yè)知識(shí)講座第91頁(yè)Vectorrings:

1.Pvectorring2.QRSvectorring3.TvectorringNormalQRSandTvectorringsQRSandTvectorringsincardiachypertrophy心電專業(yè)知識(shí)講座第92頁(yè)心電專業(yè)知識(shí)講座第93頁(yè)心電專業(yè)知識(shí)講座第94頁(yè)心電專業(yè)知識(shí)講座第95頁(yè)Whatwillhappenifheartrateistoofast?1.Decreaseincardiacoutput

2.Instabilityofcardiacelectrophysiology,VF3.Heartfailure心電專業(yè)知識(shí)講座第96頁(yè)EpicardiogramHR333bpmVFHR200bpmPeriodicHR300bpmAlternance心電專業(yè)知識(shí)講座第97頁(yè)P(yáng)acingInterval(ms)CL-PI(ms)300250220200190180(VF)PacingInterval(ms)301297303300207172205176VFAB500msPerioddoublingbifercationandchaosduringrapidpacing心電專業(yè)知識(shí)講座第98頁(yè)P(yáng)erioddoublingbifurcationandchaos心電專業(yè)知識(shí)講座第99頁(yè)P(yáng)eriod-doublingbifurcationtochaosduringrapidpacing室顫PacingInterval（ms）△CycleLength(ms)心電專業(yè)知識(shí)講座第100頁(yè)CycleNumberPCL300msPCL190msPCL170msPCL160ms,VF規(guī)則模式（正常）ABAB模式（交替）ABCDABCD模式渾沌（chaos）CL(ms)心率加緊時(shí)出現(xiàn)激動(dòng)周期倍增和VF誘發(fā)心電專業(yè)知識(shí)講座第101頁(yè)室速向室顫轉(zhuǎn)化時(shí)倍周期分岔和渾沌現(xiàn)象規(guī)則心跳(心率200BPM)2.交替節(jié)律(ABAB模式）(心率300BPM)3.ABCDABCD模式(心率316BPM)4.渾沌(chaos),室顫激動(dòng)周期(心率333BPM)心電專業(yè)知識(shí)講座第102頁(yè)024681012141618160180200220240A024681012141618240250260240220210D024681012141618160200180220260140240024681012141618120140160