Safety and efficacy of ultrasound-enhanced thrombolysis in the treatment of acute middle cerebral artery infarction: A critically appraised topic

BACKGROUND:: Despite appropriate therapy with intravenous (IV) tissue plasminogen activator (tPA), a significant proportion of patients with acute middle cerebral artery (MCA) infarction continue to suffer residual disability or death. The therapeutic use of transcranial Doppler ultrasonography (TCD) concomitantly with IV tPA is speculated to increase recanalization rates and improve clinical outcomes in patients with acute MCA stroke. OBJECTIVE:: To critically appraise the evidence concerning the safety and efficacy of the simultaneous delivery of IV tPA and continuous TCD monitoring as an acute therapy in patients with MCA territory infarction. METHODS:: The objective was addressed through the development of a structured, critically appraised topic. This incorporated a clinical scenario, background information, a structured question, literature search strategy, results, critical appraisal, clinical bottom line, and expert commentary from vascular neurology. RESULTS:: In a multicenter phase II randomized controlled study, 126 patients with acute MCA stroke were randomized to receive treatment with IV tPA and continuous TCD monitoring or placebo monitoring. Complete recanalization or dramatic clinical recovery within 2 hours after the administration of a tPA bolus occurred in 31 patients in the target group (49%), as compared with 19 patients in the control group (30%); P=0.03. At 3 months, of the patients eligible for follow-up, 22 of 53 (42%) in the target group and 14 of 49 (29%) in the control group had favorable outcomes; P=0.20. Four symptomatic intracerebral hemorrhages were noted in each group. CONCLUSIONS:: Therapeutic use of continuous TCD monitoring concomitantly with IV tPA increases recanalization rates in patients with acute MCA stroke relative to treatment with IV tPA alone without increasing the complication of intracerebral hemorrhage.