Recanalization of the MCA should play an important role in dramatic recovery after t-PA therapy in patients with ICA occlusion

J Neurol Sci. 2009 Oct 15;285(1-2):130-3. doi: 10.1016/j.jns.2009.06.017. Epub 2009 Jul 1.


Background and purpose: 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).

Conclusion: 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.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Carotid Artery Diseases / drug therapy*
  • Carotid Artery Diseases / pathology
  • Carotid Artery Diseases / physiopathology
  • Carotid Artery, Internal / drug effects*
  • Carotid Artery, Internal / pathology
  • Carotid Artery, Internal / physiopathology
  • Female
  • Fibrinolytic Agents / therapeutic use*
  • Follow-Up Studies
  • Humans
  • Magnetic Resonance Angiography
  • Magnetic Resonance Imaging
  • Male
  • Middle Cerebral Artery / drug effects*
  • Middle Cerebral Artery / pathology
  • Middle Cerebral Artery / physiopathology
  • Prospective Studies
  • Stroke / drug therapy*
  • Stroke / pathology
  • Stroke / physiopathology
  • Time Factors
  • Tissue Plasminogen Activator / therapeutic use*
  • Treatment Outcome


  • Fibrinolytic Agents
  • Tissue Plasminogen Activator