HeartHeart RateHeart FailureHeart DiseasesLiving DonorsHeart TransplantationHeart Defects, CongenitalFetal HeartActivities of Daily LivingHeart ValvesHeart AtriaHeart BlockMyocardiumHeart Arrest, InducedHeart Function TestsMyocardial ContractionTime FactorsAssisted Living FacilitiesMyocardial IschemiaRisk FactorsMyocytes, CardiacCoronary DiseaseHemodynamicsCardiac Output, LowVentricular Function, LeftPerfusionHeart, ArtificialHeart Failure, SystolicMyocardial InfarctionCardiomyopathy, DilatedCardiomegalyFollow-Up StudiesHeart InjuriesProspective StudiesHeart Rate, FetalHeart SeptumCardiotonic AgentsStroke VolumeCardiomyopathiesEchocardiographyRheumatic Heart DiseaseMyocardial Reperfusion InjuryHeart ArrestTreatment OutcomeHeart Valve ProsthesisLiving WillsVentricular Dysfunction, LeftDogsChronic DiseaseAdrenergic beta-AntagonistsHeart Failure, DiastolicAmerican Heart AssociationIndependent LivingVentricular RemodelingOxygen ConsumptionCross-Sectional StudiesAge FactorsRats, Sprague-DawleyCohort StudiesPrevalenceAutonomic Nervous SystemCardiac Pacing, ArtificialDisease Models, AnimalHeart Septal DefectsHypoplastic Left Heart SyndromeHeart NeoplasmsRats, WistarRetrospective StudiesExercise TestNational Heart, Lung, and Blood Institute (U.S.)Natriuretic Peptide, BrainUnited StatesVentricular PressureModels, CardiovascularSympathetic Nervous SystemRisk AssessmentResidence CharacteristicsSex FactorsBiological MarkersSystolePredictive Value of TestsRabbitsCalciumSocioeconomic FactorsPrognosisDiastoleEndocardiumIncidenceSeverity of Illness IndexCardiovascular DiseasesAgingIsoproterenolPropanolaminesInfant, NewbornHeart Septal Defects, VentricularRNA, MessengerMicroscopy, FluorescenceIschemic Preconditioning, MyocardialLuminescent ProteinsExercise