Heart FailureDeath, Sudden, CardiacHeartDeathHeart RateMyocytes, CardiacArrhythmias, CardiacCardiac Output, LowHeart DiseasesCause of DeathMyocardiumHeart Failure, SystolicStroke VolumeMyocardial InfarctionCell DeathFollow-Up StudiesElectrocardiographyTime FactorsTreatment OutcomeRisk FactorsVentricular Dysfunction, LeftVentricular Function, LeftCardiomyopathy, DilatedProspective StudiesHeart TransplantationEchocardiographyCardiomyopathiesCardiac OutputCardiac Pacing, ArtificialPrognosisHeart Failure, DiastolicHemodynamicsNatriuretic Peptide, BrainMyocardial ContractionDefibrillators, ImplantableAdrenergic beta-AntagonistsCardiomegalyVentricular RemodelingMyocardial IschemiaRisk AssessmentPredictive Value of TestsCardiotonic AgentsChronic DiseaseRetrospective StudiesTachycardia, VentricularBrain DeathHeart Defects, CongenitalHeart VentriclesExercise TestCardiac Surgical ProceduresHeart ArrestHeart Function TestsDeath, SuddenVentricular FibrillationTreatment FailureProportional Hazards ModelsSurvival AnalysisBiological MarkersCoronary DiseaseHeart AtriaCardiomyopathy, HypertrophicSurvival RateDisease Models, AnimalKaplan-Meier EstimateAnti-Arrhythmia AgentsDogsCardiac CatheterizationHospitalizationSeverity of Illness IndexCardiovascular AgentsElectrocardiography, AmbulatoryFetal HeartSystoleCohort StudiesAngiotensin-Converting Enzyme InhibitorsVentricular DysfunctionIncidenceLong QT SyndromeDiureticsCoronary Artery DiseaseHeart Conduction SystemDiastoleBlood PressureCardiac Resynchronization TherapyHeart-Assist DevicesTissue DonorsKidney Failure, ChronicPropanolaminesTissue and Organ ProcurementHeart ValvesHypertrophy, Left VentricularFibrosisEchocardiography, DopplerMultivariate AnalysisHeart BlockPacemaker, ArtificialAtrial Natriuretic FactorUnited StatesTroponin TElectric Countershock