Atrial FlutterEchocardiographyCatheter AblationEchocardiography, TransesophagealEchocardiography, Three-DimensionalEchocardiography, DopplerTricuspid ValveAtrial FibrillationElectrocardiographyHeart AtriaEchocardiography, StressPericarditisPropafenoneHeart BlockAnti-Arrhythmia AgentsEchocardiography, Doppler, ColorElectrophysiologic Techniques, CardiacElectric CountershockProcainamideCardiac Pacing, ArtificialHeart Conduction SystemAtrial Function, RightBody Surface Potential MappingTachycardia, SupraventricularVena Cava, InferiorDisopyramideEchocardiography, Doppler, PulsedAtrial FunctionFlecainideHeart DiseasesTachycardiaAmiodaroneDobutamineAtrial Function, LeftFollow-Up StudiesAtrial Premature ComplexesRefractory Period, ElectrophysiologicalCardiac CatheterizationPulmonary VeinsProspective StudiesHeart Defects, CongenitalTreatment OutcomeMitral ValveHeart Septal Defects, AtrialVentricular Dysfunction, LeftVentricular Function, LeftTachycardia, ParoxysmalTachycardia, Ectopic AtrialHydrops FetalisHeart VentriclesCryosurgeryFluoroscopyArrhythmias, CardiacRecurrenceAtrial AppendageStroke VolumeCoronary SinusFetal DiseasesElectrophysiologyAtrioventricular NodePredictive Value of TestsTime FactorsSensitivity and SpecificityHeart SeptumMitral Valve InsufficiencySick Sinus SyndromeDogsCardiac CathetersElectrocardiography, AmbulatoryFeasibility StudiesCardiac Surgical ProceduresCardiac VolumeButylscopolammonium BromideTachycardia, Sinoatrial Nodal ReentryAtrial SeptumHeartHeart Valve DiseasesRetrospective StudiesDiastoleObserver VariationSystoleVenae CavaeCardiomyopathiesHeart RatePostoperative ComplicationsHeart NeoplasmsExercise TestMyocardial ContractionPacemaker, ArtificialEdrophoniumSotalolReproducibility of ResultsEmbolismEndocardiumAortic ValveCardiotonic AgentsBundle of HisSurgery, Computer-AssistedDigoxinFetal Heart