Heart VentriclesHeartMyocardiumHeart RateHeart FailureHeart Defects, CongenitalHeart DiseasesAnterior ChamberCerebral VentriclesHeart TransplantationFetal HeartThird VentricleFourth VentricleHeart AtriaHeart ValvesLateral VentriclesMyocardial ContractionCerebral Ventricle NeoplasmsHeart BlockVentricular Function, LeftHeart Function TestsHemodynamicsEchocardiographyMyocytes, CardiacHeart Arrest, InducedTime FactorsMyocardial IschemiaDogsHeart SeptumDiffusion Chambers, CultureCardiomegalyStroke VolumeVentricular FunctionCardiomyopathy, DilatedPerfusionVentricular Dysfunction, LeftCardiomyopathiesCoronary DiseaseVentricular RemodelingMyocardial InfarctionHeart InjuriesEndocardiumCardiac Output, LowModels, CardiovascularCardiac Pacing, ArtificialCardiotonic AgentsVentricular Function, RightDiastoleVentricular PressureRats, Sprague-DawleyRats, WistarAtmosphere Exposure ChambersSystoleDisease Models, AnimalHeart, ArtificialHeart Septal Defects, VentricularHypoplastic Left Heart SyndromeMyocardial Reperfusion InjuryHeart Valve ProsthesisHeart NeoplasmsHeart Failure, SystolicHeart Septal DefectsRisk FactorsHeart Rate, FetalAdrenergic beta-AntagonistsRheumatic Heart DiseaseFollow-Up StudiesProspective StudiesHeart ArrestTreatment OutcomeOxygen Consumption