Heart SeptumHeart AtriaHeartSeptum of BrainHeart RateVentricular SeptumSeptum PellucidumAtrial SeptumNasal SeptumHeart FailureAtrial FunctionHeart DiseasesHeart Defects, CongenitalFetal HeartHeart TransplantationMyocardial ContractionHeart ValvesAtrial FibrillationHeart BlockEchocardiographyHeart NeoplasmsPulmonary VeinsAtrial Function, RightDogsCardiac Pacing, ArtificialHeart Conduction SystemMyocardiumCatheter AblationElectrophysiologic Techniques, CardiacHeart VentriclesHeart Septal DefectsHeart Arrest, InducedSinoatrial NodeMyocytes, CardiacHeart Septal Defects, AtrialAtrioventricular NodeHeart Septal Defects, VentricularHeart Function TestsHemodynamicsEndocardiumMyocardial IschemiaCardiomegalyVentricular Function, LeftGuinea PigsHeart InjuriesVena Cava, SuperiorCardiotonic AgentsPerfusionEchocardiography, TransesophagealTime FactorsCardiomyopathiesIsoproterenolMyxomaCoronary DiseaseElectrocardiographyCardiomyopathy, DilatedTreatment OutcomeCardiac Surgical ProceduresAtrial Function, LeftRefractory Period, ElectrophysiologicalModels, CardiovascularStroke VolumeRheumatic Heart DiseasePulmonary AtresiaAdrenergic beta-AntagonistsCardiac Output, LowCardiac CatheterizationTachycardiaAtrial FlutterAction PotentialsSeptal NucleiAnti-Arrhythmia AgentsTricuspid ValveRats, Sprague-DawleyBundle of HisBody Surface Potential MappingHeart AneurysmMyocardial InfarctionAtrial AppendageVentricular Dysfunction, LeftRats, WistarFollow-Up StudiesPacemaker, ArtificialVentricular RemodelingDisease Models, AnimalEchocardiography, DopplerRisk FactorsProspective StudiesSympathetic Nervous SystemHypoplastic Left Heart SyndromeHeart, ArtificialVentricular PressureHeart Failure, SystolicCardiomyopathy, HypertrophicHeart Valve ProsthesisVagus NerveChronic DiseaseRabbitsPulmonary ArteryPericardium