Ventricular Dysfunction, LeftEchocardiographyEchocardiography, Three-DimensionalEchocardiography, DopplerEchocardiography, TransesophagealEchocardiography, Doppler, ColorEchocardiography, StressStroke VolumeCardiac Resynchronization TherapyVentricular Function, LeftHeart FailureCardiac Pacing, ArtificialHeart VentriclesElectrocardiographyMitral Valve InsufficiencyHeart NeoplasmsEchocardiography, Doppler, PulsedMitral ValveHeart Valve DiseasesCardiac-Gated Single-Photon Emission Computer-Assisted TomographyPredictive Value of TestsVentricular DysfunctionCardiomyopathiesSensitivity and SpecificityAortic ValveBundle-Branch BlockProspective StudiesSystoleVentricular RemodelingTreatment OutcomeHypertrophy, Left VentricularDobutamineMyocardial ContractionFollow-Up StudiesObserver VariationCardiomyopathy, DilatedMyocardial Perfusion ImagingPacemaker, ArtificialGated Blood-Pool ImagingDiastoleHypertension, PulmonaryTime FactorsVentricular Function, RightReproducibility of ResultsPrognosisVentricular Dysfunction, RightMyocardiumSeverity of Illness IndexRetrospective StudiesExercise TestFeasibility StudiesTomography, Emission-Computed, Single-PhotonHeart DiseasesArrhythmias, CardiacCardiac CatheterizationImage Interpretation, Computer-AssistedMagnetic Resonance Imaging, CineVentricular SeptumHeart AtriaTomography, X-Ray ComputedHemodynamicsHeart Septal Defects, AtrialHeart Failure, DiastolicCardiac Output, LowHeart Defects, CongenitalRisk FactorsContrast MediaMyocardial InfarctionTricuspid ValveMyocardial IschemiaCardiotonic AgentsTorsion, MechanicalHeartCardiac Resynchronization Therapy DevicesHeart Failure, SystolicFetal HeartEchocardiography, Four-DimensionalHeart SeptumElectric CountershockBlood Flow VelocityCoronary CirculationHeart Valve ProsthesisCicatrixTricuspid Valve InsufficiencyNatriuretic Peptide, BrainAortic Valve InsufficiencyTechnetium Tc 99m SestamibiPatient SelectionHeart Conduction SystemAortic Valve StenosisCoronary AngiographyMitral Valve ProlapseMitral Valve StenosisDefibrillators, ImplantableAtrial Function, LeftCase-Control StudiesDipyridamoleCardiac VolumeHeart Function TestsPericardial Effusion