MyocardiumNeural ConductionHeart VentriclesHeart Conduction SystemHeartMyocardial ContractionIsolated Noncompaction of the Ventricular MyocardiumVentricular FunctionDogsAtrioventricular NodeMyocardial StunningHeart AtriaMyocytes, CardiacPapillary MusclesAction PotentialsPericardiumMyocardial IschemiaCardiomyopathiesElectrocardiographyMyocardial InfarctionCoronary CirculationArrhythmias, CardiacBupranololAequorinCardiomyopathy, DilatedHeart BlockCardiotonic AgentsModels, CardiovascularMyocardial Reperfusion InjuryConnexin 43CardiomegalyFerretsEchocardiographyTime FactorsEndocardiumCardiac Pacing, ArtificialHeart FailureRabbitsRefractory Period, ElectrophysiologicalVentricular Function, LeftPurkinje FibersCalciumFetal HeartHeart Defects, CongenitalElectric StimulationVentricular DysfunctionHemodynamicsVentricular RemodelingElectrophysiologyCoronary VesselsVentricular Dysfunction, LeftGap JunctionsAtrial FunctionGuinea PigsStimulation, ChemicalPerfusionHeart SeptumSinoatrial NodeDepression, ChemicalSwineDisease Models, AnimalRats, WistarSarcolemmaCardiac Complexes, PrematureCardiac MyosinsEndocardial FibroelastosisHeart RateIodobenzenesMyocardial ReperfusionAnti-Arrhythmia AgentsRats, Sprague-DawleyCoronary DiseaseAdrenergic beta-AgonistsReceptors, Adrenergic, betaHypertrophy, Left VentricularIsoproterenolConnexinsFibrosisBone ConductionSarcoplasmic ReticulumAdrenergic beta-1 Receptor AgonistsMedian NerveDose-Response Relationship, DrugElectrophysiologic Techniques, CardiacMyosin Heavy ChainsSystoleTomography, Emission-Computed, Single-PhotonRNA, MessengerVentricular FibrillationPhenanthridinesTissue SurvivalMitochondria, HeartHeart DiseasesImmunohistochemistryBundle of HisTachycardia, VentricularReceptors, Adrenergic, beta-1Arrhythmogenic Right Ventricular DysplasiaBenzophenanthridinesAnimals, Newborn