Heart Conduction SystemAtrioventricular NodeNeural ConductionHeartMuscle ContractionBundle of HisPurkinje FibersHeart BlockHeart RateSinoatrial NodeConnexinsIsometric ContractionMyocardial ContractionMyocardiumElectrocardiographyAtrioventricular BlockHeart AtriaArrhythmias, CardiacHeart VentriclesT-Box Domain ProteinsVentricular FunctionHeterotaxy SyndromeUterine ContractionAction PotentialsMyocytes, CardiacHeart DiseasesWolff-Parkinson-White SyndromeSp4 Transcription FactorHeart Defects, CongenitalElectrophysiologyHeart FailureConnexin 43Cardiac Pacing, ArtificialAcetylthiocholineCardiac ElectrophysiologyGene Expression Regulation, DevelopmentalElectric StimulationRefractory Period, ElectrophysiologicalModels, CardiovascularDogsMuscle, SmoothGATA6 Transcription FactorTime FactorsRabbitsDextrocardiaBundle-Branch BlockNAV1.5 Voltage-Gated Sodium ChannelThiolester HydrolasesCnidariaLac OperonHeart SeptumAnti-Arrhythmia AgentsCardiomyopathiesHeart TransplantationAntigens, CD57Lamin Type AAporphinesElectrophysiological ProcessesTachycardia, Atrioventricular Nodal ReentrySitus InversusMuscle, SkeletalElectromyographyGuinea PigsUbiquitin ThiolesteraseTachycardiaCalciumVectorcardiographyDeath, Sudden, CardiacCardiomyopathy, DilatedTelemetryMice, TransgenicSodium ChannelsFetal HeartBone ConductionMedian NerveChick EmbryoPericardiumBradycardiaPacemaker, ArtificialMotor NeuronsVasoconstrictionIsotonic ContractionHomeodomain ProteinsDesminMyosinsUlnar NerveElectrophysiologic Techniques, CardiacHeart ValvesBiological ClocksAtrial FunctionCell LineageHyperpolarization-Activated Cyclic Nucleotide-Gated ChannelsMusclesPeripheral NervesDose-Response Relationship, DrugRats, Sprague-DawleyTibial NerveMice, KnockoutDisease Models, AnimalOrganogenesis