Collateral CirculationCoronary CirculationCoronary AngiographyCollateral LigamentsCircle of WillisKidney CalicesArterial Occlusive DiseasesCerebrovascular CirculationCerebral AngiographyCoronary OcclusionAngiographyLiver CirculationHypertension, PortalMedial Collateral Ligament, KneeAngina PectorisIschemiaLigationConstriction, PathologicBalloon OcclusionCoronary VesselsRegional Blood FlowCoronary DiseaseBlood Flow VelocityMagnetic Resonance AngiographyCineangiographyCarotid Artery, InternalCeliac ArteryBlood CirculationCerebral ArteriesAngioplasty, Balloon, CoronaryDoppler EffectCerebral Arterial DiseasesCoronary StenosisHindlimbFemoral ArteryMoyamoya DiseaseHemodynamicsCarotid Artery, ExternalMyocardial InfarctionNeovascularization, PhysiologicAngiography, Digital SubtractionCarotid StenosisMyocardial IschemiaBrain IschemiaTomography, X-Ray ComputedElectrocardiographyInfarction, Middle Cerebral ArteryPhlebographyCardiac CatheterizationTime FactorsDogsEmbolization, TherapeuticArteriesCerebral InfarctionExtracorporeal CirculationPulmonary CirculationTreatment OutcomeCoronary Artery DiseaseBlood PressureCarotid Artery DiseasesProspective Studies