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Prehospital Thrombolysis: A Manual from Berlin
05:52

Prehospital Thrombolysis: A Manual from Berlin

Published on: November 26, 2013

Clinical importance of microbleeds in patients receiving IV thrombolysis

W Kakuda1, V N Thijs, M G Lansberg

  • 1Stanford Stroke Center, Stanford University Medical Center, Palo Alto, CA, USA. wkakuda@stanford.edu

Neurology
|October 26, 2005
PubMed
Abstract

Insights

Cerebral microbleeds (MBs) on gradient echo imaging do not significantly increase the risk of brain hemorrhage in stroke patients receiving IV tissue plasminogen activator (tPA) within 3 to 6 hours of symptom onset.

Area of Science:

  • Neurology
  • Radiology
  • Cardiovascular Research

Background:

  • Cerebral microbleeds (MBs) detected by gradient echo (GRE) imaging are a potential risk factor for hemorrhagic complications.
  • Intravenous tissue plasminogen activator (IV tPA) is a common treatment for acute ischemic stroke.

Purpose of the Study:

  • To investigate the association between baseline cerebral microbleeds (MBs) and hemorrhagic complications after IV tPA treatment in acute ischemic stroke patients.
  • To determine if pre-existing MBs increase the risk of symptomatic or asymptomatic hemorrhage following thrombolysis.

Main Methods:

  • Prospective evaluation of acute ischemic stroke patients treated with IV tPA within 3-6 hours of symptom onset.
  • MRI scans including GRE imaging performed before, during, and after IV tPA treatment.
  • Comparison of hemorrhagic complication rates in patients with and without baseline MBs.

Main Results:

  • MBs were identified in 15.7% of patients on baseline GRE imaging.
  • No significant difference in symptomatic or asymptomatic hemorrhagic complications was observed between patients with and without baseline MBs.
  • Patients with baseline MBs had a 0% rate of symptomatic intracerebral hemorrhage compared to 11.9% in those without MBs.

Conclusions:

  • The presence of cerebral microbleeds on GRE imaging does not substantially elevate the risk of brain hemorrhage after IV tPA administration.
  • This finding suggests that IV tPA can be safely administered in stroke patients with MBs detected on baseline GRE imaging within the specified time window.

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