Oral Presentation Australian and New Zealand Stroke Organisation Conference 2025

Intravenous thrombolysis in patients with acute ischemic stroke and cerebral microbleeds: results from the ENCHANTED trial (121616)

Zien Zhou 1 , Yilun Ge 2 , Sohei Yoshimura 3 , Takako Torii-Yoshimura 3 , Yuki Sakamoto 4 , Xiaoqiu Liu 1 , Cheryl Carcel 1 , Xiaoying Chen 1 , Leibo Liu 1 , Mark Parsons 5 , Richard Lindley 6 , Joanna Wardlaw 7 , Craig Anderson 1 , Candice Delcourt 1
  1. The George Institute For Global Health, University Of New South Wales, Barangaroo, NSW, Australia
  2. Department of Neurology, The Second Affiliated Hospital of Soochow University, Suzhou, China
  3. Department of Cerebrovascular Medicine, National Cerebral and Cardiovascular Center, Osaka, Japan
  4. Department of Neurological Science, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan
  5. South Western Clinical School, University of New South Wales, Sydney, Australia
  6. Sydney Medical School, University of Sydney, Sydney, Australia
  7. Edinburgh Imaging, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK

Objective: To determine associations between cerebral microbleeds (CMB) and intracerebral hemorrhage (ICH) and functional recovery after thrombolysis in participants of the Enhanced Control of Hypertension and Thrombolysis Stroke Study (ENCHANTED).

Methods: Patients with T2*-weighted brain MRI within 6 hours after acute ischemic stroke (AIS) were included. Associations between CMB (primary predictor), burden (0, 1, 2-4, or ≥5 CMBs), and location (deep, lobar, mixed deep-lobar) and any intracerebral hemorrhage (ICH) (primary outcome), symptomatic ICH (sICH), 90-day disability or death (modified Rankin scale [mRS] score 2-6), and other unfavorable functional outcomes (mRS 3-6, 6, and shift) were explored in logistic regression models, and by alteplase dose stratification.

Results: Of 311 eligible AIS participants, 111 (35.7%) had CMB(s) and this was not associated with a significant increase in any ICH (adjusted odds ratio 1.49, 95% confidence interval [CI] 0.87-2.54) or sICH (2.05, 0.92-4.56). However, the presence of CMB(s) was associated with 90-day disability or death (1.75, 1.04-2.94) and other unfavorable functional outcomes. Comparable associations were seen between CMB burden (defined ordinally categorical; any ICH 1.16 [0.90-1.50]; mRS 2-6 1.44 [1.11-1.87]) or mixed deep-lobar location distribution (any ICH 1.42 [0.61-3.29]; mRS 2-6 3.66 [1.48-9.05]) and these outcomes. There were no differences in associations between CMB presence/burden/location and outcomes across different alteplase doses (Pinteraction >0.051).

Conclusions: In ENCHANTED, CMB(s) is associated with 90-day unfavorable function recovery but not with increased likelihood of ICH in post-intravenous thrombolytic AIS. Low-dose alteplase may not offer safety for AIS with CMB(s).