Recanalization of the MCA should play an important role in dramatic recovery after t-PA therapy in patients with ICA occlusion.
OBJECTIVE
The intravenous t-PA thrombolysis is not thought to be effective in most patients with internal carotid artery (ICA) occlusion. However, we have sometimes observed dramatic recovery in patients with ICA occlusion after t-PA therapy. The aim of the present study was to investigate the mechanism of dramatic recovery in such patients.


METHODS
Consecutive ICA occlusion patients treated with t-PA were prospectively studied. MRI, including MRA, was performed before and within 1 h and 24 h after t-PA thrombolysis. Patients were divided into 2 groups: dramatic recovery (D group) and non-dramatic recovery (ND group).


RESULTS
The subjects consisted of 21 consecutive stroke patients (14 males; mean age, 76.5+/-8.4 years). Six (28.6%) patients (D group) had dramatic improvement and 15 (71.4%) patients (ND group) did not. The frequency of partial or complete recanalization within 1 h and 24 h after t-PA infusion was 14.3% and 50.0% for the ICA, 9.5% and 40.0% for the MCA, and 23.8% and 65.0% for the ICA or MCA, respectively. There was no difference in the frequency of ICA recanalization 24 h after t-PA infusion between the 2 groups (66.7% for D group vs. 42.9% for ND group, P=0.629); however, MCA recanalization was more frequent in the D group than in the ND group (100.0% vs. 14.3%, P=0.0004).


CONCLUSIONS
Recanalization of the MCA, which provides collateral flow, appears to play an important role in dramatic recovery after t-PA therapy in patients with ICA occlusion.
Kimura
Kazumi
K
Department of Stroke Medicine, Kawasaki Medical School, 577 Matsushima, Kurashiki, Okayama 701-0192, Japan. kimurak@med.kawasaki-m.ac.jp
Iguchi
Yasuyuki
Y
Shibazaki
Kensaku
K
Iwanaga
Takeshi
T
Aoki
Junya
J
D000368:Aged; D000369:Aged, 80 and over; D002340:Carotid Artery Diseases / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D002343:Carotid Artery, Internal / Q000187:drug effects* / Q000473:pathology / Q000503:physiopathology; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D005500:Follow-Up Studies; D006801:Humans; D018810:Magnetic Resonance Angiography; D008279:Magnetic Resonance Imaging; D008297:Male; D020768:Middle Cerebral Artery / Q000187:drug effects* / Q000473:pathology / Q000503:physiopathology; D011446:Prospective Studies; D020521:Stroke / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use*; D016896:Treatment Outcome
D005343:Fibrinolytic Agents; D010959:Tissue Plasminogen Activator