Arrhythmias, CardiacElectrocardiographyMyocytes, CardiacArrhythmia, SinusAnti-Arrhythmia AgentsDeath, Sudden, CardiacHeartLong QT SyndromeHeart Conduction SystemTachycardia, VentricularVentricular FibrillationVentricular Premature ComplexesElectrocardiography, AmbulatoryCardiac Complexes, PrematureAtrial FibrillationTachycardiaHeart RateEncainideNAV1.5 Voltage-Gated Sodium ChannelMyocardiumHeart VentriclesCardiac Surgical ProceduresCardiac OutputCardiac Pacing, ArtificialEther-A-Go-Go Potassium ChannelsModels, CardiovascularDeath, SuddenTime FactorsCatheter AblationPotassium Channels, Voltage-GatedBradycardiaCardiac ElectrophysiologyMoricizineKCNQ1 Potassium ChannelHeart DiseasesAction PotentialsDogsFlecainideHeart AtriaAtrial FlutterSodium ChannelsTachycardia, SupraventricularElectrophysiologic Techniques, CardiacMyocardial ContractionDigitalis GlycosidesHeart ArrestAtrial Premature ComplexesMyocardial InfarctionTreatment OutcomeChlorofluorocarbons, MethaneHeart FailureAmiodaroneKCNQ Potassium ChannelsMyocardial IschemiaTorsades de PointesCardiomyopathiesDefibrillators, ImplantableCardiomegalyFollow-Up StudiesElectrophysiologyCardiac Imaging TechniquesHypokalemiaHeart BlockEchocardiographyAconitinePotassium ChannelsPericardiumBody Surface Potential MappingRisk FactorsElectric CountershockProspective StudiesAndersen SyndromeCardiac CatheterizationRetrospective StudiesVentricular FunctionTelemetryPostoperative ComplicationsRyanodine Receptor Calcium Release ChannelDisease Models, AnimalAutonomic Nervous SystemHemodynamicsPacemaker, ArtificialBlood PressureSyncopeCardiac TamponadeCalciumMutationPatch-Clamp TechniquesMyocardial Reperfusion InjuryVentricular Function, LeftCardiomyopathy, DilatedCardiotonic AgentsProcainamideBrugada SyndromeEndocardiumVentricular DysfunctionTachycardia, Ectopic AtrialPredictive Value of TestsHeart InjuriesPurkinje Fibers