Atrial FlutterArrhythmias, CardiacCatheter AblationElectrocardiographyAtrial FibrillationAnti-Arrhythmia AgentsHeart Conduction SystemTricuspid ValveHeart AtriaElectrophysiologic Techniques, CardiacCardiac Pacing, ArtificialHeart BlockPropafenoneElectric CountershockProcainamidePericarditisTachycardiaArrhythmia, SinusTachycardia, SupraventricularBody Surface Potential MappingFlecainideMyocytes, CardiacAmiodaroneAtrial Premature ComplexesElectrocardiography, AmbulatoryHeartAtrial Function, RightTachycardia, VentricularDisopyramideDeath, Sudden, CardiacLong QT SyndromeVena Cava, InferiorTachycardia, Ectopic AtrialAtrial FunctionElectrophysiologyHeart RateVentricular FibrillationRefractory Period, ElectrophysiologicalHeart DiseasesDogsTreatment OutcomeFollow-Up StudiesCardiac Surgical ProceduresTime FactorsTachycardia, ParoxysmalCardiac Complexes, PrematureVentricular Premature ComplexesAtrioventricular NodePulmonary VeinsHeart VentriclesRecurrenceMyocardiumCryosurgeryHydrops FetalisFluoroscopyProspective StudiesEncainideNAV1.5 Voltage-Gated Sodium ChannelEchocardiographyAction PotentialsCardiac OutputCoronary SinusCardiac CatheterizationPacemaker, ArtificialFetal DiseasesModels, CardiovascularEther-A-Go-Go Potassium ChannelsSick Sinus SyndromeBradycardiaDeath, SuddenPostoperative ComplicationsButylscopolammonium BromideDigoxinHeart Defects, CongenitalEndocardiumCardiac CathetersSotalolPotassium Channels, Voltage-GatedRetrospective StudiesAtrial Function, LeftMoricizineCardiac ElectrophysiologyEchocardiography, TransesophagealKCNQ1 Potassium ChannelCardiomyopathiesTachycardia, Sinoatrial Nodal ReentryDefibrillators, ImplantableBundle of HisSodium ChannelsRisk FactorsMyocardial ContractionDigitalis GlycosidesHeart ArrestMyocardial InfarctionVenae CavaeHeart FailureChlorofluorocarbons, MethaneTachycardia, Atrioventricular Nodal ReentryAtrial AppendageEdrophonium