Venous ThrombosisPortal VeinThrombosisHypertension, PortalHypertensionUltrasonography, DopplerVeinsThrombophlebitisUltrasonography, Doppler, ColorFemoral VeinPortal SystemHypertension, PulmonaryIliac VeinUpper Extremity Deep Vein ThrombosisPhlebographyMesenteric VeinsSplenic VeinDoppler EffectRenal VeinsPulmonary EmbolismAnticoagulantsVaricose VeinsJugular VeinsSaphenous VeinPopliteal VeinSubclavian VeinUltrasonography, Doppler, PulsedSinus Thrombosis, IntracranialIntracranial ThrombosisCoronary ThrombosisPortal PressureVena Cava, InferiorBlood Flow VelocityBlood PressureHypertension, RenalFibrin Fibrinogen Degradation ProductsEchocardiography, Doppler, PulsedUltrasonography, Doppler, DuplexHeparin, Low-Molecular-WeightUltrasonography, Doppler, TranscranialHepatic VeinsRisk FactorsTreatment OutcomeAxillary VeinBudd-Chiari SyndromeThrombophiliaCerebral VeinsProspective StudiesEchocardiography, Doppler, ColorPortasystemic Shunt, SurgicalCarotid Artery ThrombosisPulmonary VeinsPostthrombotic SyndromeHypertension, RenovascularAntihypertensive AgentsTime FactorsEsophageal and Gastric VaricesRetrospective StudiesHeparinVenous ThromboembolismLiver CirculationFollow-Up StudiesLegUltrasonographyProtein S DeficiencyFactor VThromboembolismThrombectomyTomography, X-Ray ComputedFibrinolytic AgentsHypertension, MalignantVena Cava FiltersWarfarinMesenteric Vascular OcclusionPregnancy Complications, CardiovascularRegional Blood FlowLiver CirrhosisPlethysmography, ImpedancePostphlebitic SyndromeStockings, CompressionPostoperative ComplicationsAngiographyIntermittent Pneumatic Compression DevicesHemorrhageUmbilical VeinsSplenorenal Shunt, SurgicalHepatic ArteryIntracranial Embolism and ThrombosisLaser-Doppler FlowmetrySplenectomyHemodynamicsVenous InsufficiencyPortacaval Shunt, SurgicalLiver TransplantationRecurrenceThrombolytic TherapyPregnancyGastrointestinal HemorrhagePulmonary ArteryIncidence