Pulmonary VeinsCatheter AblationPulmonary Veno-Occlusive DiseaseAtrial FibrillationVeinsHeart AtriaElectrophysiologic Techniques, CardiacSaphenous VeinCryosurgeryBlood VesselsPortal VeinVaricose VeinsHeart Conduction SystemBody Surface Potential MappingTachycardia, Ectopic AtrialFemoral VeinCardiac CathetersJugular VeinsTreatment OutcomeVena Cava, SuperiorRecurrenceMesenteric VeinsLymphatic VesselsPhlebographyConstriction, PathologicTachycardia, ParoxysmalUmbilical VeinsFluoroscopyRenal VeinsIliac VeinScimitar SyndromeDogsRetinal VesselsAnti-Arrhythmia AgentsAtrial SeptumSurgery, Computer-AssistedImaging, Three-DimensionalElectrocardiographyAutonomic DenervationFollow-Up StudiesAtrial Premature ComplexesHepatic VeinsCoronary VesselsPopliteal VeinAtrial AppendageAtrial FunctionBreath HoldingPulmonary ArteryAtrial Function, LeftCatheterizationEchocardiography, TransesophagealTime FactorsTomography, X-Ray ComputedElectrocardiography, AmbulatoryAtrial FlutterAzygos VeinCardiac Pacing, ArtificialElectrophysiological PhenomenaCardiac Complexes, PrematureCerebral VeinsMagnetic Resonance AngiographySplenic VeinRetinal VeinSubclavian VeinPulmonary CirculationAngiographyEquipment DesignLymphangiectasisSinoatrial NodeTachycardiaCoronary SinusTomography, Spiral ComputedHeart Septal Defects, AtrialBlood Flow VelocityProspective StudiesEndothelium, VascularRefractory Period, ElectrophysiologicalPulmonary AtresiaBrachiocephalic VeinsFeasibility StudiesVenae CavaeRespiratory-Gated Imaging TechniquesPericardiumMultidetector Computed TomographyGanglia, AutonomicVena Cava, InferiorMuscle, Smooth, VascularVascular MalformationsAxillary VeinEchocardiographyRetinal Vein OcclusionPostoperative ComplicationsRetrospective Studies