HRV in Sleep Apnea Detection and Sleep Stability

  • View
    214

  • Download
    0

Embed Size (px)

Transcript

  • HRVinSleepApneaDetectionandSleepStability

    Assessment

    JosephE.Mietus

    BethIsraelDeaconessMedicalCenterHarvardMedicalSchool

    Boston,MA

    HRV2006

  • OverviewofECGbasedsleepapneadetection

    Hilberttransformdetectionofsleepapnea Sleepapneaheartrateoscillations Hilberttransformdetectionalgorithm

    Cardiopulmonarycoupling(CPC) ECGderivedrespiration(EDR) CPCdetectionalgorithm Sleepspectrograms

    Normalsleep Sleepstateswitching Sleepapneadetection

    Outline

  • OverviewofECGbasedsleepapneadetection

    Hilberttransformdetectionofsleepapnea Sleepapneaheartrateoscillations Hilberttransformdetectionalgorithm

    Cardiopulmonarycoupling(CPC) ECGderivedrespiration(EDR) CPCdetectionalgorithm Sleepspectrograms

    Normalsleep Sleepstateswitching Sleepapneadetection

  • SleepApnea

    Intermittentcessationofbreathingduringsleep Affectsmillionsworldwidewithincreased

    morbidityandmortality Diagnosisbypolysomnographyexpensiveand

    encumberingandnotreadilyrepeated Needforsimple,easilyimplementedscreening

    anddetectiontechniques

  • PhysioNet/ComputersinCardiologyChallengetoDetectSleepApneafroma

    SingleLeadECG

    http://www.physionet.org/challenge/2000

  • ECGchangesassociatedwithsleepapnea

    Changesduetoneuroautonomicandmechanicalfactors

    Cyclicvariationsinheartrate

    CyclicvariationsinECGamplitudeormorphology

  • AutomatedTechniquestoDetectSleepApneafromtheECG

    Timedomaintechniques RRvariability Movingaverages Patterndetection

    Frequencydomaintechniques Spectralanalysisofheartratevariability Hilberttransform Wavelets Timefrequencymaps

    ECGmorphologybasedtechniques ECGderivedrespiration ECGpulseenergy Rwaveduration QRSScomponentamplitude

    Penzel,etal.MedBiolEngComput2002;40:402407

  • OverviewofECGbasedsleepapneadetection

    Hilberttransformdetectionofsleepapnea Sleepapneaheartrateoscillations Hilberttransformdetectionalgorithm

    Cardiopulmonarycoupling(CPC) ECGderivedrespiration(EDR) CPCdetectionalgorithm Sleepspectrograms

    Normalsleep Sleepstateswitching Sleepapneadetection

  • Sleepapneatypicallyassociatedwith0.010.04Hz.oscillationsinheartrate

  • SleepApneaHeartRateOscillations

    Transientandnonstationarywithvaryingamplitudesandfrequencies

    DifficulttodetectandlocalizeusingstandardFourierspectraltechniques

    Hilberttransformcanbeusedtoquantifyinstantaneousamplitudesandfrequenciesofheartrateoscillations requiresbandwidthlimitedsignal

  • HilbertTransformSleepApneaDetectionOverview

    ExtractNNintervalseriesfromRRintervals

    FilterandresampleNNintervalseries

    ComputeHilbertTransformation

    Calculatelocalmeans,standarddeviationsandtimewithinthresholdlimitsforbothHilbertamplitudesandfrequencies

    Detectperiodswhenamplitudeandfrequencymeasuresarewithinspecifiedlimits

  • RRIntervalPreprocessing

    Extractnormalsinusnormalsinus(NN)intervals

    FilterNNintervaloutliers

    Resampleat1Hz

    BandpassfilterLowpassfilter(3dbat0.09Hz)Highpassfilter(3dbat0.01Hz)

  • RRintervalpreprocessing

  • HilbertTransformation

    CalculateinstantaneousamplitudesandfrequenciesoffilteredNNintervalseries

    Medianfilteramplitudesandfrequencies

    NormalizeHilberttransformamplitudes

    SetminimumHilbertamplitudethreshold(dependentondataset)andmaximumHilbertfrequencythreshold(0.06Hz)

  • HilbertTransformoffilteredNNintervals

  • SleepApneaDetectionParameters

    Calculatelocalmeans,standarddeviationsandtimewithinthresholdlimitsforbothHilbertamplitudesandfrequenciesover5minutewindowsincrementedeachminute

    Selectparameterlimitsthatgivethehighestpercentageofminutebyminutetruepositiveandtruenegativeapneadetections

    Detectsequenceswhereallsixamplitudeandfrequencymeasuresarewithintheirspecifiedlimitsforaminimumof15minutes

  • DetectionofsleepapneausingtheHilberttransform

  • HilbertTransformSleepApneaDetectionResults

    PhysioNetCombinedTrainingandTestSets

    Correctlyclassified54outof60apnea/controlsubjects(90.0%)

    Correctlyclassified28576outof34313minuteswith/withoutOSA(83.3%)

  • http://www.physionet.org/physiotools/apdetSourcecodefreelyavailable

  • FailureoftheHilberttransformapneadetectorintheabsenceofrespiratorymodulationofheartrate

  • OverviewofECGbasedsleepapneadetection

    Hilberttransformdetectionofsleepapnea Sleepapneaheartrateoscillations Hilberttransformdetectionalgorithm

    Cardiopulmonarycoupling(CPC) ECGderivedrespiration(EDR) CPCdetectionalgorithm Sleepspectrograms

    Normalsleep Sleepstateswitching Sleepapneadetection

  • ECGDerivedRespiration(EDR):respirationmodulatesECGamplitudes

    ~10secondsofdata

    ECG

    Respirationsignal

    Moody,etal.ComputCardiol1985:12;113116

  • ECGderivedrespirationintheabsenceofapparentrespiratorymodulationofheartrate

  • ECGbasedCardiopulmonaryCouplingDetector

    Sleepdisorderedbreathing(SDB)isassociatedwithlowfrequencyoscillationsinheartrate

    SDBalsoassociatedwithlowfrequencyvariationsinECGwaveformduetochestwallmovementduringrespiration

    UsingacontinuousECG,wecombinebothsignalstomeasurethecouplingbetweenrespirationandheartratevariations

  • CardiopulmonaryCoupling(CPC)Overview

    EmploysFourierbasedtechniquestoanalyzetheRRintervalseriesanditsassociatedEDRsignal Measuresthecommonpowerofthetwosignalsat

    differentfrequenciesbycalculatingtheircrossspectralpower

    Measuresthesynchronizationofthesignalsatdifferentfrequenciesbycomputingtheircoherence

    Usestheproductofcoherenceandcrossspectralpowertoquantifythedegreeofcardiopulmonarycouplingatdifferentfrequencies

  • CPCDetectionAlgorithm

    Identifybeatsandclassifyasnormalorectopic ExtractNNintervaltimeseriesanditsassociatedEDR

    timeseries Filteroutliersduetofalseormisseddetections Linearlyresampleat2Hz. Calculatetheproductofcrosspowerandcoherence

    overamoving1024pointwindow Plotcoherentcrosspoweratvariousfrequenciesasa

    functionoftime(sleepspectrogram)

    Thomas,etal.SLEEP2005;28(9):11511161.

  • SingleleadECGsignal

    QRSamplitudevariationmeasurements NNintervalmeasurements

    ECGderivedrespiration(EDR)timeseries

    Heartratevariabilitytimeseries

    Calculationofproductofcrossspectralpower&coherence(CPCmethod)forthetwotimeseries

    AutomatedSleepPhysiologyDetection:usingratioofCPCindifferentfrequencybands

    cubicsplineresampling

    Beatlabeling

    Selectionofnormalsinus(N)beatsOutlierfiltering

    Patentpending

    CPCDetectionAlgorithm

  • CPCRevealsTwoCardiopulmonaryCouplingRegimes

    Highfrequencycoupling(0.10.4Hz.band)correspondstorespiratorysinusarrhythmia

    Lowfrequencycoupling(0.010.1Hz.band)associatedwithSDB

    CouplingstatesdonotcorrespondwithstandardsleepstagingbutdofollowscoringusingtheEEGbasedCyclicAlternatingPattern(CAP)paradigm CAP:unstable,lightsleep;lowfrequencycoupling NonCAP:stable,deepsleep;highfrequency

    coupling

  • CPCDetectionofCAP/NonCAPSleepStates

    UsingappropriatethresholdsforhighandlowfrequencycouplingmagnitudesandtheirratiositispossibletodetectCAP/NonCAPsleepstates

    ParametersselectedthatgivethegreatestsensitivityandspecificityforthedetectionofCAP(C),NonCAP(NC)andWake/REM(WR)inscoredsleepstudies

    ParametersalsoselectedthatgivethegreatestsensitivityandspecificityforapneadetectioninPhysioNetsleepapneadatabase

  • Sleepspectrograminahealthy22yrold

    Highfrequencycoupling

    Lowfrequencycoupling

  • Sleepspectrograminahealthy56yrold

    Highfrequencycoupling

    Lowfrequencycoupling

  • Sleepstateswitchinginahealthysubject

  • Sleepspectrogramandapneadetection

  • Sleepspectrogramandapneadetectioninasevereapneasubject

  • Sleepspectrogramandapneadetectioninasevereapneasubject

  • Narrowbandandbroadbandlowfrequencycouplinginsleepapneasyndromes

    Narrowbandcoupling(centralapnea)

    Broadbandcoupling(obstructiveapnea)

  • Conclusions

    SleepdisorderedbreathingsyndromescanbedetectedinafullyautomatedfashionfromasingleleadECG

    Stable(NonCAP)andunstable(CAP)sleepstatescanbedetectedbymeasuringthecouplingbetweenrespirationandheartrate

    Inhealthyindividualssleepstatespontaneouslyswitchesbetweenstableandunstablethroughoutthenight

    Lossofhighfrequencycouplingisindicativeofunstablesleep/pathologicstates

  • References

    GoldbergerAL,AmaralLAN,GlassL,etal.PhysioBank,PhysioToolkit,andPhysioNet:componentsofanewResearchResourceforComplexPhysiologicSignals.Circulation2000;101:e215220

    MietusJM,PengCK,IvanovPC,etal.Detectionofobstructivesleepapneafromcardiacinterbeatintervaltimeseries.ComputCardiol2000;27:753756

    MoodyGB,MarkR,ZoccolaA,etal.DerivationofrespiratorysignalsfrommultileadECGs.ComputCardiol1985;12:113116

    PenzelT,McNamesJ,deChazalP,etal.Systematiccomparisonofdifferentalgorithmsforapnoeadetectionbasedonelectrocardiogramrecordings.MedBiolEngComput2002;40:402407

    TerazanoMG,ParrinoL,FioritiG,etal.Atlas,rules,andrecordingtechniquesforthescoringofcyclicalternatingpattern(CAP)inhumansleep.SleepMed2001;2:537553

    ThomasRJ,MietusJE,PengCK,GoldbergerAL.Anelectrocardiogrambasedtechniquetoassesscardiopulmonarycouplingduringsleep.SLEEP2005;28(9):11511161