title: Progression of middle cerebral artery occlusive disease and its relationship with further vascular events after stroke.
abstract: BACKGROUND
  Serial changes of flow velocities of transcranial Doppler ultrasound (TCD) in symptomatic middle cerebral artery (MCA) occlusive disease may be related to the occurrence of further vascular events, but prospective data are lacking.
  
  
  METHODS
  We conducted a prospective study on patients with cerebral ischemia who were hospitalized with symptomatic MCA stenosis or occlusion. We repeated TCD examinations 6 months after the initial examinations and recorded any stroke or coronary events during this period. The changes of MCA flow velocities were categorized as normalized artery, stable artery, and progressed artery, which were determined according to the changes of MCA velocities at 6 months.
  
  
  RESULTS
  We studied 143 consecutive patients who had relevant MCA occlusive diseases (107 with stenosis and 36 with occlusion). At 6 months, the velocities in the MCA returned to normal in 42 patients (29%), they were stable in 80 patients (62%), and they progressed in 13 patients (9%). The number of clinical events varied significantly among the 3 groups: there were 2 patients (4.8%) with clinical events in the normal group, 11 patients (12.5%) with clinical events in the stable group, and 5 patients (38.5%) with clinical events in the progressed group (P=0.004). The 18 recurrent events included 10 recurrent strokes, 5 transient ischemic attacks, and 3 acute coronary syndromes.
  
  
  CONCLUSIONS
  Progression of MCA occlusive diseases is associated with an increased risk of vascular events. Further studies are required to establish the value of serial TCD examinations in predicting future clinical events.
authors.affiliation: Division of Neurology, Department of Medicine and Therapeutics, the Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong, SAR. ks-wong@cuhk.edu.hk
authors.forename: Ka Sing
authors.initials: KS
authors.lastname: Wong
authors.forename: Huan
authors.initials: H
authors.lastname: Li
authors.forename: Wynnie W M
authors.initials: WW
authors.lastname: Lam
authors.forename: Yu Leung
authors.initials: YL
authors.lastname: Chan
authors.forename: Richard
authors.initials: R
authors.lastname: Kay
mesh_terms: D000368:Aged; D001783:Blood Flow Velocity; D001921:Brain / Q000098:blood supply / Q000473:pathology; D002560:Cerebrovascular Circulation; D002561:Cerebrovascular Disorders / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology*; D003327:Coronary Disease / Q000150:complications / Q000175:diagnosis*; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006723:Hong Kong; D006801:Humans; D020244:Infarction, Middle Cerebral Artery / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000503:physiopathology / Q000648:ultrastructure; D011446:Prospective Studies; D012075:Remission, Spontaneous; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D015996:Survival Rate; D017585:Ultrasonography, Doppler, Transcranial