HeartHeart RateBlood CirculationHeart FailureHeart DiseasesHeart Defects, CongenitalExtracorporeal CirculationHeart TransplantationPulmonary CirculationFetal HeartHeart ValvesCollateral CirculationHeart AtriaHemodynamicsHeart BlockMyocardiumEnterohepatic CirculationTime FactorsHeart Arrest, InducedCerebrovascular CirculationCoronary CirculationHeart Function TestsMyocardial ContractionHeart ArrestPlacental CirculationSplanchnic CirculationMyocardial IschemiaPerfusionDogsRegional Blood FlowCoronary DiseaseBlood Circulation TimeMyocytes, CardiacLiver CirculationHeart, ArtificialVascular ResistanceVentricular Function, LeftBlood Flow VelocityCardiac Output, LowMyocardial InfarctionRats, Sprague-DawleyHeart Rate, FetalRisk FactorsDisease Models, AnimalOxygen ConsumptionEchocardiographyCardiomegalyHeart SeptumStroke VolumeCardiomyopathy, DilatedHeart Failure, SystolicRats, WistarCardiotonic AgentsTreatment OutcomeModels, CardiovascularProspective StudiesCardiomyopathiesMyocardial Reperfusion InjuryHeart InjuriesAdrenergic beta-AntagonistsHeart Valve ProsthesisRabbitsRheumatic Heart DiseaseFollow-Up StudiesVentricular Dysfunction, LeftTissue DistributionHypoplastic Left Heart SyndromeSympathetic Nervous SystemPulmonary ArteryChronic DiseaseVentricular RemodelingVasodilator AgentsHeart Failure, DiastolicCross CirculationAmerican Heart AssociationAutonomic Nervous SystemLiverHeart Septal DefectsBiological MarkersCardiac Pacing, ArtificialDose-Response Relationship, DrugVentricular PressureMice, Inbred C57BLOxygenExercise TestNatriuretic Peptide, BrainRenal CirculationVasodilationBlood PressureNorepinephrineHeart NeoplasmsAssisted CirculationNitric OxideAnoxiaKidneyInjections, IntravenousCardiopulmonary ResuscitationNational Heart, Lung, and Blood Institute (U.S.)RNA, MessengerRetrospective Studies