Ischemic Attack, TransientStrokeCerebrovascular DisordersCarotid StenosisRisk FactorsEndarterectomy, CarotidAtrial FibrillationBrain IschemiaRecurrenceCarotid Artery, InternalCarotid Artery DiseasesAnticoagulantsProspective StudiesTreatment OutcomeAspirinIntracranial EmbolismCerebral InfarctionFollow-Up StudiesRisk AssessmentTime FactorsIntracranial Embolism and ThrombosisCerebral AngiographyUltrasonography, Doppler, TranscranialDipyridamoleCarotid ArteriesPlatelet Aggregation InhibitorsMagnetic Resonance AngiographyTomography, X-Ray ComputedEchocardiography, TransesophagealSeverity of Illness IndexPrognosisRetrospective StudiesGreat BritainCerebrovascular CirculationPredictive Value of TestsFibrinolytic AgentsCohort StudiesReferral and ConsultationVertebrobasilar InsufficiencyIncidenceEnglandAge FactorsPatient SelectionEmbolismIntracranial ArteriosclerosisAcute DiseaseMagnetic Resonance ImagingEndarterectomySecondary PreventionStentsDiffusion Magnetic Resonance ImagingMyocardial InfarctionCerebral HemorrhageBrainAngioplasty, BalloonAngioplastyMyocardial IschemiaSensitivity and SpecificityCardiovascular DiseasesPostoperative ComplicationsNeurologyTriageIntracranial Arterial DiseasesIschemiaMigraine DisordersRiskAmaurosis FugaxEarly DiagnosisFeasibility StudiesBrain InfarctionComplement Membrane Attack ComplexCerebral ArteriesIntracranial HemorrhagesComorbidityMoyamoya DiseaseEmergency Medical ServicesWarfarinRegistries