Sonothrombolysis for Acute Ischemic Stroke
Several studies have consistently demonstrated the capability of ultrasound to enhance the lysis of intra-arterial thrombi in acute ischemic stroke during systemic intravenous thrombolysis with tissue plasimogen activator (tPA), an intervention also called sonothrombolysis.
Material and Methods
To quantify the potential benefits of sonothrombolysis in acute ischemic stroke.
To quantify the potential harms of sonothrombolysis.
Types of Studies
Randomized controlled trials with clear allocation concealment.
Types of Participants
Patients admitted to hospital with acute ischemic stroke.
Types of Interventions
Sonothrombolysis versus intravenous tPA therapy alone or conventional treatment.
Survival free of significant disability at the end of follow-up.
Case fatality, vessel recanalization, symptomatic and asymptomatic hemorrhagic transformation, and cerebral hemorrhage.
We included 5 studies, with a total of 233 patients randomized. However, not all patients were available for all outcomes: for instance, follow-up at 3 months (death and dependency) was available for 206 patients (88.4%). Three studies used transcranial color-coded duplex, and 2 used transcranial color doppler. The duration of sonothrombolysis varied from 1 to 2 hours. When we considered all the 5 studies, we observed a statistically significant difference for the primary outcome (death or disability at 3 months; 206 patients; odds ratio, 0.50; 95% confidence interval [CI], 0.27–0.91). Results for death were neutral (206 patients; odds ratio, 1.00; 95% CI, 0.46–2.16); failure to recanalize was lower in the sonothrombolysis group (230 patients; odds ratio, 0.28; 95% CI, 0.16–0.50); and there was a nonsignificant trend for increasing cerebral hemorrhages (233 patients; odds ratio, 2.35; 95% CI, 0.95–5.80). When including patients only treated with tPA, the results were very similar.
Our results indicate that sonothrombolysis performed in patients with recent onset ischemic stroke with evidence of middle cerebral artery or posterior cerebral artery occlusion produces a significant increase in the recanalization rate (Figure), associated with a nonsignificant increase of hemorrhagic transformation of the cerebral infarction. There was a statistically significant clinical improvement at the 3-month follow-up in terms of death plus disability rate, although with very wide CIs.
Implications for Practice
There is insufficient evidence to establish the effectiveness and safety of sonothrombolysis in routine clinical practice.
Implications for Research
Sonothrombolysis is a promising technique but there is a clear need for a new multicenter randomized trial.
We thank Prof Peter Langhorne and the editorial team in Edinburgh for their help.
- Received November 2, 2012.
- Accepted December 13, 2012.
- © 2013 American Heart Association, Inc.
- Ricci S,
- Dinia L,
- Del Sette M,
- Anzola P,
- Mazzoli T,
- Cenciarelli S,
- Gandolfo C