Heart AtriaHeart SeptumAtrial Function, RightAtrial FunctionSeptum of BrainAtrial SeptumVentricular SeptumSeptum PellucidumHeart NeoplasmsNasal SeptumHeart Conduction SystemVena Cava, SuperiorAtrial FlutterAtrial FibrillationElectrophysiologic Techniques, CardiacSinoatrial NodeCatheter AblationVena Cava, InferiorCardiac Pacing, ArtificialHeartVentricular Function, RightElectrocardiographyDogsMyxomaEchocardiography, TransesophagealFistulaMyocardial ContractionPulmonary VeinsEchocardiographyHeart Septal Defects, AtrialAtrioventricular NodeHeart VentriclesBody Surface Potential MappingTricuspid ValveVentricular Dysfunction, RightSinus of ValsalvaBundle of HisRefractory Period, ElectrophysiologicalCardiac CatheterizationHeart RateCoronary SinusHuman RightsTachycardiaEndocardiumHeart InjuriesPericardiumHeart BlockPacemaker, ArtificialCardiac Surgical ProceduresAtrial Premature ComplexesGuinea PigsHemangiosarcomaMyocardiumAtrial AppendageTachycardia, Ectopic AtrialHeart Septal Defects, VentricularPulmonary ArteryHeart Defects, CongenitalTricuspid Valve StenosisTachycardia, Atrioventricular Nodal ReentryTomography, X-Ray ComputedHeart DiseasesIsoproterenolAction PotentialsVascular FistulaHeart AneurysmElectrophysiologyTachycardia, SupraventricularTreatment OutcomeHypertrophy, Right VentricularVenae CavaeTricuspid AtresiaCardiac TamponadeSuperior Vena Cava SyndromeFetal HeartPericardial EffusionAzygos VeinEbstein AnomalyTachycardia, ParoxysmalElectric CountershockCoronary Vessel AnomaliesArrhythmias, CardiacTricuspid Valve InsufficiencyAtrial Function, LeftFluoroscopyVagus NerveCardiopulmonary BypassVascular NeoplasmsFatal OutcomePulmonary EmbolismTime FactorsSick Sinus SyndromeAnti-Arrhythmia AgentsAtrial Natriuretic FactorHemodynamicsPericarditisElectric StimulationMagnetic Resonance ImagingEchocardiography, Doppler, ColorCor Triatriatum