PerfusionHeartHeart RatePerfusion ImagingMyocardial Perfusion ImagingHeart FailureHeart DiseasesHeart TransplantationHeart Defects, CongenitalTomography, Emission-Computed, Single-PhotonFetal HeartChemotherapy, Cancer, Regional PerfusionMyocardiumCoronary CirculationHeart ValvesMyocardial IschemiaHeart AtriaRegional Blood FlowHemodynamicsCerebrovascular CirculationTime FactorsMyocardial ContractionHeart Arrest, InducedHeart BlockCoronary DiseaseTechnetium Tc 99m SestamibiOrganotechnetium CompoundsDogsHeart Function TestsContrast MediaVentricular Function, LeftBlood Flow VelocityMyocardial InfarctionExercise TestMicrocirculationRats, Sprague-DawleyMagnetic Resonance AngiographyRadiopharmaceuticalsVentilation-Perfusion RatioEchocardiographyMyocytes, CardiacOxygen ConsumptionLaser-Doppler FlowmetryRats, WistarThallium RadioisotopesMagnetic Resonance ImagingProspective StudiesBlood VolumeStroke VolumeSensitivity and SpecificityAdenosineVentricular Dysfunction, LeftVasodilator AgentsDipyridamoleDisease Models, AnimalCardiotonic AgentsMyocardial Reperfusion InjuryReproducibility of ResultsPulmonary CirculationTreatment OutcomeMyocardial ReperfusionPredictive Value of TestsTomography, X-Ray ComputedHeart ArrestHeart, ArtificialRisk FactorsCardiac Output, LowCardiomyopathy, DilatedImage Processing, Computer-AssistedVascular ResistanceModels, CardiovascularOxygenFollow-Up StudiesCardiomegalyCardiomyopathiesOximesRabbitsNitrogen RadioisotopesOrgan PreservationIschemiaImage EnhancementGated Blood-Pool ImagingHeart SeptumHeart Failure, SystolicHeart InjuriesHeart Rate, FetalAdrenergic beta-AntagonistsPressureGadolinium DTPATechnetium Tc 99m ExametazimeRheumatic Heart DiseaseCapillariesHeart Valve ProsthesisBrainVentricular RemodelingNorepinephrineBlood PressureSympathetic Nervous SystemKidneyRats, Inbred Strains