Purpose: The objective of this study was to assess early recanalization rates following intravenous recombinant tissue plasminogen activator (rt-PA) therapy by magnetic resonance angiography (MRA) or digital subtraction angiography (DSA) in patients with acute ischemic stroke in order to plan a clinical investigation for a newly developed sonothrombolysis system.
Methods: We retrospectively enrolled consecutive patients with acute ischemic stroke who were treated with intravenous rt-PA. Early recanalization within 2 hours and 24 hours after the initiation of rt-PA was evaluated by modified Mori grade on follow-up MRA or Thrombolysis in Cerebral Infarction (TICI) score on follow-up DSA.
Results: A total of 384 patients were enrolled (243 men, age 74 ± 13 years) in the study. Patients were subdivided into groups based upon arterial location as follows: 63 patients in the internal carotid artery (ICA), 181 in the middle cerebral artery (MCA [M1 and M2 segments]), 5 in the anterior cerebral artery (ACA), and 14 in the posterior cerebral artery (PCA). Among patients with major artery occlusion (ICA, MCA, ACA, or PCA), the rates of recanalization were 37.2% within 2 hours and 57.4% within 24 hours; 8 of 232 patients (3.4%) had symptomatic intracranial hemorrhage within the initial 36 hours, and 76 of 225 patients (33.8%) had a favorable functional outcome (modified Rankin Scale (mRS) 0-1) at 3 months.
Conclusions: We assessed early recanalization rates and clinical outcome following intravenous rt-PA therapy.