DobutamineMyocardiumCardiotonic AgentsEchocardiography, StressMyocardial ContractionMyocardial StunningHeartEchocardiographyMyocardial IschemiaAdrenergic beta-AgonistsVentricular Function, LeftCoronary CirculationHemodynamicsExercise TestAdrenergic beta-1 Receptor AgonistsVentricular Dysfunction, LeftCoronary DiseaseDogsTissue SurvivalMyocardial InfarctionTomography, Emission-Computed, Single-PhotonThallium RadioisotopesHydrazonesHeart VentriclesTechnetium Tc 99m SestamibiHeart RateCoronary AngiographyElectrocardiographyStroke VolumeDipyridamoleSensitivity and SpecificityAmrinoneMilrinonePredictive Value of TestsMagnetic Resonance Imaging, CineMyocardial RevascularizationCardiomyopathy, DilatedPyridazinesTime FactorsVentricular FunctionSystoleEnoximoneMyocardial Reperfusion InjuryHeart FailureTomography, Emission-ComputedMyocardial ReperfusionCardiomyopathiesMyocytes, CardiacOxygen ConsumptionSympathomimeticsRadiopharmaceuticalsSwineCoronary VesselsDose-Response Relationship, DrugCardiac OutputBlood PressureCatecholaminesReceptors, Adrenergic, betaDiastolePropanolaminesVentricular RemodelingAdrenergic beta-AntagonistsOrganotechnetium CompoundsFeasibility StudiesAtropineRadionuclide VentriculographyVasodilator AgentsVentricular PressurePericardiumObserver VariationHeart Function TestsProspective StudiesIodobenzenesContrast MediaCoronary StenosisEchocardiography, DopplerInfusions, IntravenousCardiac VolumeDisease Models, AnimalAdenosineReproducibility of ResultsHeart AtriaCardiac Output, LowReceptors, Adrenergic, beta-1CardiomegalyPerfusionPrognosisHistory, Early Modern 1451-1600Cardiac CatheterizationFollow-Up StudiesMagnetic Resonance ImagingCalciumStimulation, ChemicalRats, Sprague-DawleyVentricular DysfunctionCoronary Artery BypassCoronary Artery DiseaseBlood Flow Velocity