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Microembolic signals at 48 hours after stroke onset contribute to new ischaemia within a week

Y Iguchi1, K Kimura, K Kobayashi

  • 1Department of Stroke Medicine, Kawasaki Medical School, 577 Matsushima, Kurashiki City, Okayama, 701-0192, Japan. yigu@med.kawasaki-m.ac.jp

Journal of Neurology, Neurosurgery, and Psychiatry
|September 12, 2007
PubMed
Abstract

Insights

Microembolic signals (MES) detected 48 hours after stroke onset are linked to new ischemic lesions on follow-up imaging. This finding highlights MES as a predictor of recurrent cerebral ischemia.

Area of Science:

  • Neurology
  • Neuroimaging
  • Vascular Neurology

Background:

  • Acute ischemic stroke requires accurate prognostication.
  • Identifying predictors of recurrent ischemia is crucial for patient management.

Purpose of the Study:

  • To investigate the association between microembolic signals (MES) and new ischemic lesions (NIL) after acute ischemic stroke.
  • To determine if MES detected within 24 or 48 hours of stroke onset predict NIL on follow-up diffusion-weighted imaging (DWI).

Main Methods:

  • 125 patients with acute ischemic stroke underwent transcranial Doppler (TCD) for MES detection at 24 and 48 hours.
  • Diffusion-weighted imaging (DWI) was performed on admission and day 7 to identify NIL.
  • Statistical analysis assessed the relationship between MES, patient characteristics, and NIL.

Main Results:

  • Microembolic signals (MES) were detected in 49% of patients within 24 hours and 29% at 48 hours.
  • New ischemic lesions (NIL) were observed in 22% of patients on follow-up DWI.
  • MES at 48 hours (OR 3.9), atrial fibrillation (OR 3.6), and arterial lesions (OR 4.3) were independent predictors of NIL.

Conclusions:

  • The presence of MES at 48 hours post-stroke is significantly associated with new ischemic lesions.
  • Atrial fibrillation and arterial lesions also independently predict recurrent cerebral ischemia.
  • These findings suggest MES may serve as a valuable biomarker for stroke recurrence risk.

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