Heart FailureHeartCardiac Output, LowStroke VolumeHeart Failure, SystolicHeart RateCardiac Resynchronization TherapyVentricular Dysfunction, LeftVentricular Function, LeftCardiac Pacing, ArtificialAdrenergic beta-AntagonistsHeart-Assist DevicesNatriuretic Peptide, BrainTreatment OutcomeHeart Failure, DiastolicChronic DiseaseCardiomyopathy, DilatedExercise ToleranceExercise TestPropanolaminesVentricular RemodelingHemodynamicsHydrazonesEchocardiographyHeart TransplantationCardiotonic AgentsFollow-Up StudiesCheyne-Stokes RespirationAngiotensin-Converting Enzyme InhibitorsProspective StudiesPrognosisDefibrillators, ImplantableCarbazolesMyocardiumPacemaker, ArtificialCardiac Resynchronization Therapy DevicesTime FactorsDiureticsHospitalizationSystolePredictive Value of TestsSleep Apnea, CentralOxygen ConsumptionPatient ReadmissionHeart DiseasesSeverity of Illness IndexMyocardial ContractionKidney Failure, ChronicHeart VentriclesBiological MarkersRetrospective StudiesDigoxinHeart Function TestsRisk FactorsPyridazinesElectrocardiographyEchocardiography, DopplerDeath, Sudden, CardiacSympathetic Nervous SystemTreatment FailureCardiovascular AgentsCardiomyopathiesVentricular DysfunctionRisk AssessmentSpironolactoneNatriuretic AgentsProportional Hazards ModelsDiastoleMineralocorticoid Receptor AntagonistsSurvival RateMyocardial IschemiaBundle-Branch BlockMetoprololCardiomegalyCase-Control StudiesCardiography, ImpedanceCardiac OutputDouble-Blind MethodBlood PressureAtrial Natriuretic FactorKaplan-Meier EstimateExerciseMyocardial InfarctionMonitoring, PhysiologicMedigoxinRespirationQuality of LifeMyocytes, CardiacSurvival AnalysisXamoterolCohort StudiesHeart Defects, CongenitalPulmonary Wedge PressureArrhythmias, CardiacAngiotensin II Type 1 Receptor BlockersTelemetryAnaerobic ThresholdRadionuclide VentriculographyVentricular Function, RightExercise Therapy