Heart RateHeartHeart FailureHeart DiseasesHeart TransplantationHeart Defects, CongenitalHeart Rate, FetalFetal HeartAutonomic Nervous SystemHeart ValvesHeart AtriaHemodynamicsBlood PressureHeart BlockMyocardiumMyocardial ContractionHeart Function TestsSympathetic Nervous SystemAdrenergic beta-AntagonistsTime FactorsElectrocardiography, AmbulatoryHeart Arrest, InducedMyocardial IschemiaBaroreflexExercise TestCoronary DiseaseOxygen ConsumptionVentricular Function, LeftDogsStroke VolumeMyocytes, CardiacCardiotonic AgentsElectrocardiographyCardiac Output, LowParasympathetic Nervous SystemTelemetryMyocardial InfarctionEchocardiographyPropranololRespirationRisk FactorsCardiomyopathy, DilatedPropanolaminesTachycardiaCardiovascular Physiological PhenomenaProspective StudiesExerciseCardiomegalyNorepinephrineCardiac Pacing, ArtificialVentricular Dysfunction, LeftHeart Failure, SystolicBradycardiaAtropineSinoatrial NodeRestMyocardial Reperfusion InjuryCardiomyopathiesHeart, ArtificialPressoreceptorsPerfusionModels, CardiovascularRats, Sprague-DawleyHeart ArrestIsoproterenolHeart SeptumHeart InjuriesSystoleRats, WistarFollow-Up StudiesRheumatic Heart DiseaseVentricular RemodelingDiastoleMetoprololHeart Valve ProsthesisPhysical ExertionDose-Response Relationship, DrugAutonomic Nervous System DiseasesReflexCardiovascular SystemArrhythmia, SinusDouble-Blind MethodTreatment OutcomeCardiac OutputDisease Models, AnimalHeart Failure, DiastolicChronic DiseaseAnti-Arrhythmia AgentsAmerican Heart AssociationPostureReference ValuesEpinephrineSignal Processing, Computer-AssistedSupine PositionPredictive Value of TestsRegional Blood FlowNatriuretic Peptide, BrainBody TemperatureAdrenergic beta-AgonistsCatecholamines