Heart FailureHeartVentricular Function, LeftMassachusettsHeart RateAdult ChildrenVentricular Dysfunction, LeftStroke VolumeEchocardiographyVentricular Function, RightHeart DiseasesHeart VentriclesMyocardiumMyocytes, CardiacRisk FactorsMyocardial ContractionCohort StudiesMyocardial InfarctionVentricular FunctionCardiac Output, LowHemodynamicsCardiovascular DiseasesFollow-Up StudiesSystoleHeart TransplantationCoronary DiseaseTime FactorsProspective StudiesCardiomyopathy, DilatedHeart Defects, CongenitalHeart Function TestsBlood PressureCardiac OutputVentricular RemodelingHeart Failure, SystolicElectrocardiographyCardiac Pacing, ArtificialCardiomyopathiesHypertrophy, Left VentricularDiastoleTreatment OutcomeRisk AssessmentNatriuretic Peptide, BrainCardiotonic AgentsPredictive Value of TestsHeart Failure, DiastolicMyocardial IschemiaCardiomegalyHeart AtriaBiological MarkersAdrenergic beta-AntagonistsPrognosisCardiac CatheterizationVentricular Dysfunction, RightChronic DiseaseArrhythmias, CardiacEchocardiography, DopplerCardiac Surgical ProceduresExercise TestLongitudinal StudiesProportional Hazards ModelsDeath, Sudden, CardiacFetal HeartDogsIncidenceSex FactorsVentricular PressureHypertensionHeart ValvesAge FactorsQuantitative Trait, HeritableCardiac VolumeRadionuclide VentriculographyVentricular DysfunctionSeverity of Illness IndexRetrospective StudiesDisease Models, AnimalIntra-Abdominal FatGenetic LinkageHeart BlockAtrial FibrillationGenome, HumanTreatment FailureMultivariate AnalysisGated Blood-Pool ImagingHeart-Assist DevicesCoronary CirculationSubcutaneous Fat, AbdominalPropanolaminesPhenotypeRegression AnalysisLinear ModelsUnited StatesHeart Arrest, InducedOxygen ConsumptionReference ValuesMyocardial Reperfusion InjuryRadionuclide AngiographyAngiotensin-Converting Enzyme InhibitorsDobutamine