CSR-CSADefinitionofCSACentralsleepapneasCSA与OSAwhenstudyingpatientswithcardiovasculardiseases,especiallythosewithHFandstroke,whereCSAismuchcommonerthaninthegeneralpopulation,distinguishingcentralfromobstructiveeventsassumesgreaterimportanceDiagnosisofCSAInpatientswithHF,adiagnosisofCSAcanbeestablishedonovernightpolysomnography,usingeitherRIPornasalpressurecannulaforrespiratorymonitoring,whenthereisanAHIofatleast5to15,andwhenatleast50%ofapneasandhypopneasarecentral.Cheyne-Stokesrespiration(CSR)CSRcanbeobservedbothduringsleepandwakefulness,althoughitappearstobefarmorecommonduringsleepWhenitoccursduringsleep,itissimplyaformofCSAwithaprolongedhyperpnea.WhenspecifyingtheoccurrenceofCSRduringsleep,wehaveusedtheterm‘‘Cheyne-Stokesrespirationwithcentralsleepapnea(CSR-CSA).’’Thepresenceofaprolongedhyperpneawithawaxing-waningpatternoftidalvolume,andprolongedcycleduration,thatdistinguishesCSRfromotherformsofperiodicbreathingasidiopathicCSAorhigh-altitudeperiodicbreathingwithoutHFAB（apnealength）=18s，21sC=nadirofSaO2BC（lung-tocarotidbodycirculationtime）=8s，26sBD(hyperpnealength)=7s，46sAD(cyclelength)=25s,65sHallMJ,AmJRespirCritCareMed1996;154:376–381PathophysioloryhyperventilationInpatientswithHFwithCSR-CSA,PaCO2tendsnottoincreasemuchmorefromwakefulnesstosleepcomparedtotheapneicthresholddoes.LoopgainXieAetal,AmJRespirCritCareMed2002;165:1245–1250.FerrierKetal,Chest2005;128:2116–2122.Thischronichyperventilationoccursbecauseofpulmonaryvagalirritantreceptorstimulationbypulmonarycongestionandincreasesincentralandperipheralchemosensitivity.LoweringwedgepressurewithdrugsorCPAPisassociatedwithariseinPaCO2andalleviationofCSRCSA.SolinPetalCirculation1999;99:1574–1579.JavaheriS.NEnglJMed1999;341:949–954.SolinPetal,AmJRespirCritCareMed2000;162:2194–2200.arousalsCSA与OSAPrevalenceRiskfactorsforCSAinCHFCardiovascularEffectsofCSR-CSACSR-CSAcontributestosympatheticactivation：Increasepreloadandafterloadand,thus,workforthedamagedmyocardiumDecreasemyocardialcontractilityVentr