Heart RateHeartPulseHeart Rate, FetalHeart FailureBlood PressureAutonomic Nervous SystemHeart DiseasesHemodynamicsHeart TransplantationHeart Defects, CongenitalFetal HeartSympathetic Nervous SystemTime FactorsBaroreflexElectrocardiography, AmbulatoryHeart AtriaElectrocardiographyAdrenergic beta-AntagonistsExercise TestHeart ValvesMyocardial ContractionMyocardiumHeart BlockPulse Therapy, DrugOxygen ConsumptionDogsHeart Function TestsTelemetryParasympathetic Nervous SystemBradycardiaPropranololRespirationStroke VolumeCardiovascular Physiological PhenomenaVentricular Function, LeftMyocardial IschemiaTachycardiaCardiac OutputExercisePhysical ExertionCardiovascular SystemAtropineCoronary DiseaseRestPressoreceptorsPulse Wave AnalysisSignal Processing, Computer-AssistedPropanolaminesNorepinephrineCardiotonic AgentsOximetryHeart Arrest, InducedSinoatrial NodeProspective StudiesReflexPulsatile FlowEchocardiographyModels, CardiovascularSystoleAutonomic Nervous System DiseasesRisk FactorsMyocardial InfarctionDose-Response Relationship, DrugMyocytes, CardiacCardiac Pacing, ArtificialArrhythmia, SinusCardiac Output, LowPostureDouble-Blind MethodSupine PositionIsoproterenolCircadian RhythmMetoprololRats, Sprague-DawleyDiastoleElectric StimulationRegional Blood FlowBlood Flow VelocityReference ValuesBody TemperatureRats, WistarEpinephrineCardiomyopathy, DilatedHypertensionFollow-Up StudiesMonitoring, PhysiologicVentricular Dysfunction, LeftAtenololOxygenHypotensionCatecholaminesArrhythmias, CardiacTreatment OutcomePulse RadiolysisAnti-Arrhythmia AgentsTilt-Table TestAnesthesiaFetal MonitoringCardiomegaly