Heart FailureCardiovascular SystemHeartHeart RateCardiovascular Physiological PhenomenaCardiac Output, LowHeart Failure, SystolicMyocardiumHemodynamicsHeart Failure, DiastolicHeart DiseasesStroke VolumeVentricular Function, LeftNatriuretic Peptide, BrainBlood PressureHeart TransplantationCardiomyopathy, DilatedAdrenergic beta-AntagonistsChronic DiseaseVentricular Dysfunction, LeftCardiovascular DiseasesMyocardial ContractionTreatment FailureVentricular RemodelingHeart Defects, CongenitalTime FactorsEchocardiographyCardiomegalyMyocytes, CardiacCardiotonic AgentsCardiovascular Physiological ProcessesTreatment OutcomeModels, CardiovascularCardiomyopathiesFetal HeartRisk FactorsHeart AtriaMyocardial InfarctionCardiac Pacing, ArtificialFollow-Up StudiesProspective StudiesDisease Models, AnimalHeart VentriclesDogsHeart Function TestsSympathetic Nervous SystemMyocardial IschemiaAngiotensin-Converting Enzyme InhibitorsPrognosisSystoleExercise TestAutonomic Nervous SystemBiological MarkersDiureticsCardiovascular AgentsAtrial Natriuretic FactorCardiovascular AbnormalitiesDiastoleCardiac OutputHeart-Assist DevicesHospitalizationElectrocardiographyPropanolaminesRats, WistarSeverity of Illness IndexVentricular PressureOxygen ConsumptionRetrospective StudiesVascular ResistanceKidney Failure, ChronicVasodilator AgentsPredictive Value of TestsBaroreflexSignal TransductionNorepinephrineEndothelium, VascularHeart ValvesHypertensionAortaRisk AssessmentExercise ToleranceDigoxinDose-Response Relationship, DrugNitric OxideVentricular DysfunctionNatriuretic PeptidesCarbazolesArrhythmias, CardiacKidneyRats, Sprague-DawleyCardiologyDouble-Blind MethodRenin-Angiotensin SystemPatient ReadmissionCoronary DiseaseBlood VesselsEchocardiography, DopplerHeart BlockProportional Hazards ModelsCohort Studies