Heart FailureVentricular Function, LeftHeartVentricular Dysfunction, LeftStroke VolumeVentricular Function, RightHeart RateVentricular FunctionEchocardiographyHeart VentriclesCardiac Output, LowMyocardial ContractionMyocardiumHemodynamicsMyocardial InfarctionCardiomyopathy, DilatedHeart Failure, SystolicSystoleHeart DiseasesVentricular RemodelingDiastoleHeart Function TestsHeart Failure, DiastolicNatriuretic Peptide, BrainTime FactorsTreatment OutcomeVentricular Dysfunction, RightCardiotonic AgentsCardiomyopathiesAdrenergic beta-AntagonistsFollow-Up StudiesHeart TransplantationElectrocardiographyEchocardiography, DopplerCardiac Pacing, ArtificialProspective StudiesChronic DiseaseMyocardial IschemiaRadionuclide VentriculographyExercise TestHypertrophy, Left VentricularHeart Defects, CongenitalVentricular PressureTreatment FailureCoronary DiseasePrognosisVentricular DysfunctionGated Blood-Pool ImagingHeart AtriaPredictive Value of TestsCardiac CatheterizationDogsMyocytes, CardiacCardiomegalyBlood PressureCardiac OutputRadionuclide AngiographyCoronary CirculationCardiac VolumeHeart-Assist DevicesAngiotensin-Converting Enzyme InhibitorsDisease Models, AnimalRisk FactorsPropanolaminesExercise ToleranceSeverity of Illness IndexDobutamineRetrospective StudiesDiureticsBiological MarkersMitral Valve InsufficiencyAtrial Function, LeftOxygen ConsumptionMetoprololPacemaker, ArtificialEchocardiography, Doppler, PulsedCarbazolesHospitalizationCineangiographyVentriculography, First-PassArrhythmias, CardiacAtrial Natriuretic FactorCardiovascular AgentsHeart BlockEchocardiography, Doppler, ColorPulmonary Wedge PressureDigoxinMyocardial Reperfusion InjuryMyocarditisAtrial FibrillationHeart ValvesMagnetic Resonance Imaging, CineRisk AssessmentDouble-Blind MethodFetal HeartSurvival RateCoronary Artery BypassFibrosisSympathetic Nervous SystemAngiocardiography