HeartHeart RateRegional Blood FlowBlood Flow VelocityHeart FailureFlow CytometryHeart DiseasesHeart Defects, CongenitalHeart TransplantationFetal HeartHeart ValvesHeart AtriaPulsatile FlowHeart BlockMyocardiumGene FlowHeart Arrest, InducedHeart Function TestsTime FactorsMyocardial IschemiaMyocardial ContractionPerfusionCoronary DiseaseMyocytes, CardiacVentricular Function, LeftHemodynamicsModels, CardiovascularCardiac Output, LowMyocardial InfarctionCerebrovascular CirculationOxygen ConsumptionEchocardiographyHeart, ArtificialHeart Rate, FetalRheologyVascular ResistanceStroke VolumeCardiomyopathy, DilatedHeart Failure, SystolicCardiomegalyCardiotonic AgentsCoronary CirculationHeart SeptumMyocardial Reperfusion InjuryRisk FactorsProspective StudiesHeart InjuriesCardiomyopathiesHeart ArrestRheumatic Heart DiseaseRats, Sprague-DawleyHeart Valve ProsthesisAdrenergic beta-AntagonistsDisease Models, AnimalOptic FlowRats, WistarLaser-Doppler FlowmetryVentricular Dysfunction, LeftHeart Failure, DiastolicTreatment OutcomeFollow-Up StudiesAmerican Heart AssociationVentricular RemodelingBlood CirculationSympathetic Nervous SystemChronic DiseaseDogsFlow Injection AnalysisDiastoleCardiac Pacing, ArtificialPeak Expiratory Flow RateRabbitsHypoplastic Left Heart SyndromeExercise TestAutonomic Nervous SystemVentricular PressureSystoleVasodilator AgentsOxygenHeart Septal DefectsEchocardiography, DopplerHeart NeoplasmsDose-Response Relationship, DrugNatriuretic Peptide, BrainReference ValuesMicrospheresPredictive Value of TestsReproducibility of ResultsNational Heart, Lung, and Blood Institute (U.S.)EndocardiumPulmonary CirculationNorepinephrineBiological MarkersIsoproterenolBlood PressureCells, CulturedHeart-Assist DevicesCalciumMicrocirculationHeart Septal Defects, Ventricular