国外生理学与解剖学学习课件教学课件PPT.ppt

18 1 anatomy physiologyiiprofessor dr edwardc deemer copyright c themcgraw hillcompanies inc permissionrequiredforreproductionordisplay dr edwarddeemerapii missedexamsdon t ifbysomemiracleyougetmetoexcusetheabsence themakeupexamwillbeessayform adeathcertificatewouldbeanexampleofanvalidexcuse attendanceattendance beontime ifyouarenot5minutesearly youarelate attendancewillbetakenandrecordedbymeduringtheclassperiod cellphonepolicyturnyourcellphonesoff nottovibrate 19 3 circulatorysystem theheart circulatorysystemheart bloodvesselsandbloodcardiovascularsystemheart arteries veinsandcapillariestwomajordivisions pulmonarycircuit rightsideofheartcarriesbloodtolungsforgasexchangesystemiccircuit leftsideofheartsuppliesbloodtoallorgansofthebody 19 4 circulatorysystem theheart grossanatomyoftheheartoverviewofcardiovascularsystemcardiacconductionsystemandcardiacmuscleelectricalandcontractileactivityofheartbloodflow heartsounds andcardiaccyclecardiacoutput 19 5 cardiovascularsystemcircuit 19 6 position size andshape locatedinmediastinum betweenlungsbase broadsuperiorportionofheartapex inferiorend tiltstotheleft taperstopoint3 5in wideatbase 5in frombasetoapexand2 5in anteriortoposterior weighs10oz 19 7 heartposition 19 8 pericardium allowshearttobeatwithoutfriction roomtoexpandandresistsexcessiveexpansionparietalpericardiumouter tough fibrouslayerofctpericardialcavityfilledwithpericardialfluidvisceralpericardium a k a epicardiumofheartwall inner thin smooth moistserouslayercoversheartsurface 19 9 pericardiumandheartwall pericardialcavitycontains5 30mlofpericardialfluid 19 10 heartwall epicardium a k a visceralpericardium serousmembranecoversheartmyocardiumthickmuscularlayerfibrousskeleton networkofcollagenousandelasticfibersprovidesstructuralsupportandattachmentforcardiacmuscleelectricalnonconductor importantincoordinatingcontractileactivityendocardium smoothinnerlining 19 11 heartchambers 4chambersrightandleftatriatwosuperior posteriorchambersreceivebloodreturningtoheartrightandleftventriclestwoinferiorchamberspumpbloodintoarteries atrioventricularsulcus separatesatria ventriclesanteriorandposteriorsulci groovesseparateventricles nextslide 19 12 externalanatomy anterior 19 13 externalanatomy posterior 19 14 heartchambers internal interatrialseptumwallthatseparatesatriapectinatemusclesinternalridgesofmyocardiuminrightatriumandbothauriclesinterventricularseptumwallthatseparatesventriclestrabeculaecarneaeinternalridgesinbothventricles 19 15 internalanatomy anterior 19 16 heartvalves atrioventricular av valvesrightavvalvehas3cusps tricuspidvalve leftavvalvehas2cusps mitral bicuspidvalve chordaetendineae cordsconnectavvalvestopapillarymuscles onfloorofventricles semilunarvalves controlflowintogreatarteriespulmonary rightventricleintopulmonarytrunkaortic fromleftventricleintoaorta 19 17 heartvalves 19 18 heartvalves 19 19 avvalvemechanics ventriclesrelaxpressuredropssemilunarvalvescloseavvalvesopenbloodflowsfromatriatoventriclesventriclescontractavvalvesclosepressurerisessemilunarvalvesopenbloodflowsintogreatvessels 19 20 operationofatrioventricularvalves 19 21 operationofsemilunarvalves 19 22 bloodflowthroughheart 19 23 anginaandheartattack anginapectorispartialobstructionofcoronarybloodflowcancausechestpainpaincausedbyischemia oftenactivitydependentmyocardialinfarctioncompleteobstructioncausesdeathofcardiaccellsinaffectedareapainorpressureinchestthatoftenradiatesdownleftarm 19 24 coronarycirculation leftcoronaryartery lca anteriorinterventricularbranchsuppliesbloodtointerventricularseptumandanteriorwallsofventriclescircumflexbranchpassesaroundleftsideofheartincoronarysulcus suppliesleftatriumandposteriorwallofleftventriclerightcoronaryartery rca rightmarginalbranchsupplieslateralratriumandventricleposteriorinterventricularbranchsuppliesposteriorwallsofventricles 19 25 venousdrainageofheart 20 drainsdirectlyintorightatriumandventricleviathebesianveins80 returnstorightatriumvia greatcardiacveinbloodfromanteriorinterventricularsulcusmiddlecardiacveinfromposteriorsulcusleftmarginalveincoronarysinuscollectsbloodandemptiesintorightatrium 19 26 coronaryvessels anterior 19 27 coronaryvessels posterior 19 28 nervesupplytoheart sympatheticnervesfromupperthoracicspinalcord throughsympatheticchaintocardiacnervesdirectlytoventricularmyocardiumcanraiseheartrateto230bpmparasympatheticnervesrightvagalnervetosanodeleftvagalnervetoavnodevagaltone normallyslowsheartrateto70 80bpm 19 29 cardiacconductionsystem propertiesmyogenic heartbeatoriginateswithinheartautorhythmic regular spontaneousdepolarizationcomponentsnextslide 19 30 cardiacconductionsystem sanode pacemaker initiatesheartbeat setsheartratefibrousskeletoninsulatesatriafromventriclesavnode electricalgatewaytoventriclesavbundle pathwayforsignalsfromavnoderightandleftbundlebranches divisionsofavbundlethatenterinterventricularseptumpurkinjefibers upwardfromapexspreadthroughoutventricularmyocardium 19 31 cardiacconductionsystem 19 32 metabolismofcardiacmuscle aerobicrespirationrichinmyoglobinandglycogenlargemitochondriaorganicfuels fattyacids glucose ketonesfatigueresistant 19 33 cardiacrhythm systole ventricularcontractiondiastole ventricularrelaxationsinusrhythmsetbysanodeat60 100bpmadultatrestis70to80bpm vagalinhibition prematureventricularcontraction pvc causedbyhypoxia electrolyteimbalance stimulants stress etc 19 34 cardiacrhythm ectopicfoci regionofspontaneousfiring notsa nodalrhythm setbyavnode 40to50bpmintrinsicventricularrhythm 20to40bpmarrhythmia abnormalcardiacrhythmheartblock failureofconductionsystembundlebranchblocktotalheartblock damagetoavnode 19 35 electrocardiogram ecg compositeofallactionpotentialsofnodalandmyocardialcellsdetected amplifiedandrecordedbyelectrodesonarms legsandchest 19 36 ecg pwavesanodefires atrialdepolarizationatrialsystoleqrscomplexventriculardepolarization atrialrepolarizationanddiastole signalobscured stsegment ventricularsystoletwaveventricularrepolarization 19 37 normalelectrocardiogram ecg 19 38 1 atrialdepolarizationbegins2 atrialdepolarizationcomplete atriacontracted 3 ventriclesbegintodepolarizeatapex atriarepolarize atriarelaxed 4 ventriculardepolarizationcomplete ventriclescontracted 5 ventriclesbegintorepolarizeatapex6 ventricularrepolarizationcomplete ventriclesrelaxed electricalactivityofmyocardium 19 39 diagnosticvalueofecg invaluablefordiagnosingabnormalitiesinconductionpathways mi heartenlargementandelectrolyteandhormoneimbalances 19 40 ecgs normalandabnormal 19 41 ecgs abnormal extrasystole noteinvertedqrscomplex misshapenqrsandtandabsenceofapwaveprecedingthiscontraction 19 42 ecgs abnormal arrhythmia conductionfailureatavnode nopumpingactionoccurs 19 43 cardiaccycle onecompletecontractionandrelaxationofall4chambersoftheheartatrialsystole ventriclediastoleatrialdiastole ventriclesystolequiescentperiod 19 44 resistanceopposesflowgreatvesselshavepositivebloodpressureventricularpressuremustriseabovethisresistanceforbloodtoflowintogreatvessels principlesofpressureandflow pressurecausesafluidtoflowpressuregradient pressuredifferencebetweentwopoints 19 45 heartsounds auscultation listeningtosoundsmadebybodyfirstheartsound s1 louderandlonger lubb occurswithclosureofavvalvessecondheartsound s2 softerandsharper dupp occurswithclosureofsemilunarvalvess3 rarelyheardinpeople 30 19 46 phasesofcardiaccycle quiescentperiodallchambersrelaxedavvalvesopenandbloodflowingintoventriclesatrialsystolesanodefires atriadepolarizepwaveappearsonecgatriacontract forceadditionalbloodintoventriclesventriclesnowcontainend diastolicvolume edv ofabout130mlofblood 19 47 isovolumetriccontractionofventricles atriarepolarizeandrelaxventriclesdepolarizeqrscomplexappearsinecgventriclescontractrisingpressureclosesavvalves heartsounds1occursnoejectionofbloodyet nochangeinvolume 19 48 ventricularejection risingpressureopenssemilunarvalvesrapidejectionofbloodreducedejectionofblood lesspressure strokevolume amountejected 70mlatrestsv edv ejectionfraction atrest 54 duringvigorousexerciseashighas90 diseasedheart 50 end systolicvolume amountleftinheart 19 49 ventricles isovolumetricrelaxation twaveappearsinecgventriclesrepolarizeandrelax begintoexpand semilunarvalvesclose dicroticnotchofaorticpress curve heartsounds2occursavvalvesremainclosedventriclesexpandbutdonotfill nochangeinvolume 19 50 ventricularfilling 3phases rapidventricularfillingavvalvesfirstopendiastasissustainedlowerpressure venousreturnatrialsystolefillingcompleted 19 51 majoreventsofcardiaccycle quiescentperiodventricularfillingisovolumetriccontractionventricularejectionisovolumetricrelaxation 19 52 eventsofthecardiaccycle 19 53 rateofcardiaccycle atrialsystole 0 1secventricularsystole 0 3secquiescentperiod 0 4sectotal0 8sec heartrate75bpm 19 54 ventricularvolumechangesatrest end systolicvolume esv 60mlpassivelyaddedtoventricleduringatrialdiastole 30mladdedbyatrialsystole 40mlend diastolicvolume edv 130mlstrokevolume sv ejectedbyventricularsystole 70mlend systolicvolume esv 60mlbothventriclesmustejectsameamountofblood 19 55 unbalancedventricularoutput 19 56 unbalancedventricularoutput 19 57 cardiacoutput co amountejectedbyventriclein1minutecardiacoutput heartratexstrokevolumeabout4to6l minatrestvigorousexercise coto21l minforfitpersonandupto35l minforworldclassathletecardiacreserve differencebetweenapersonsmaximumandrestingco withfitness withdisease 19 58 heartrate pulse surgeofpressureinarteryinfantshavehrof120bpmormoreyoungadultfemalesavg 72 80bpmyoungadultmalesavg 64to72bpmhrrisesagainintheelderlytachycardia restingadulthrabove100stress anxiety drugs heartdiseaseor bodytemp bradycardia restingadulthr 60insleepandendurancetrainedathletes 19 59 chronotropiceffects positivechronotropicagents hrnegativechronotropicagents hrcardiaccenterofmedullaoblongataanautonomiccontrolcenterwithtwoneuronalpools acardioacceleratorycenter sympathetic andacardioinhibitorycenter parasympathetic 19 60 sympatheticnervoussystem cardioacceleratorycenterstimulatessympatheticcardiacnervestosanode avnodeandmyocardiumthesenervessecretenorepinephrine whichbindsto adrenergicreceptorsintheheart positivechronotropiceffect copeaksathrof160to180bpmsympatheticn s can hrupto230bpm limitedbyrefractoryperiodofsanode butsvandco lessfillingtime 19 61 parasympatheticnervoussystem cardioinhibitorycenterstimulatesvagusnervesrightvagusnerve sanodeleftvagusnerve avnodesecretesach acetylcholine whichbindstomuscarinicreceptorsnodalcellshyperpolarized hrslowsvagaltone backgroundfiringrateholdshrtosinusrhythmof70to80bpmseveredvagusnerves intrinsicrate 100bpm maximumvagalstimulation hraslowas20bpm 19 62 inputstocardiaccenter higherbraincentersaffecthrcerebralcortex limbicsystem hypothalamussensoryoremotionalstimuli rollercoaster irsaudit proprioceptorsinformcardiaccenteraboutchangesinactivity hr beforemetabolicdemandsarisebaroreceptorssignalcardiaccenteraortaandinternalcarotidarteriespressure signalratedrops cardiaccenter hrifpressure signalraterises cardiaccenter hr 19 63 inputstocardiaccenter chemoreceptorssensitivetobloodph co2andoxygenaorticarch carotidarteriesandmedullaoblongataprimarilyrespiratorycontrol mayinfluencehr co2 hypercapnia causes h levels maycreateacidosis ph 7 35 hypercapniaandacidosisstimulatescardiaccenterto