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Assessing Cortical Cerebral Microinfarcts on High Resolution MR Images
08:39

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Published on: November 20, 2015

Cerebral microembolism in acute myocardial infarction

Z G Nadareishvili1, Z Choudary, C Joyner

  • 1Stroke Research Unit, Sunnybrook & Women's College Health Sciences Centre, University of Toronto, Canada. znadareishvilili19@hotmail.com

Stroke
|December 3, 1999
PubMed

Insights

Cerebral microemboli, or high-intensity transient signals (HITS), were detected in 17% of acute myocardial infarction patients. These signals were linked to reduced left ventricular function and predicted stroke events.

Area of Science:

  • Cardiology
  • Neurology
  • Medical Imaging

Background:

  • Cerebral microemboli, detected as high-intensity transient signals (HITS) via transcranial Doppler (TCD), are a concern in acute myocardial infarction (AMI).
  • Understanding the frequency and predictors of HITS in AMI patients is crucial for assessing embolic risk.

Purpose of the Study:

  • To determine the incidence of HITS using TCD in patients with AMI.
  • To identify risk factors associated with HITS in this population.
  • To explore the relationship between HITS and clinical embolic events, including stroke.

Main Methods:

  • 112 consecutive patients admitted to an acute coronary care unit within 72 hours were monitored for HITS using TCD.
  • 2-dimensional echocardiograms were performed on all patients during the study period.
  • Patients with inadequate ultrasound insonation were excluded from the analysis.

Main Results:

  • HITS were detected in 17% of the studied AMI patients.
  • A significantly higher frequency of HITS was observed in patients with reduced left ventricular (LV) ejection fraction (<65%), akinetic LV segments, and LV thrombus.
  • Stroke was significantly more common in patients who exhibited cerebral microemboli.

Conclusions:

  • Despite antithrombotic therapy, HITS were present in 17% of AMI patients.
  • Reduced LV function, akinetic myocardial segments, and LV thrombus are associated with an increased occurrence of HITS.
  • HITS may serve as a predictor of clinical embolic events, including stroke, in AMI patients.
Abstract

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