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Platelet and leukocyte activation after myocardial infarction. Influence of enalapril

C Sylvén1, I Hagerman, K E Karlberg

  • 1Karolinska Institute, Department of Medicine, Huddinge University Hospital, Stockholm, Sweden.

European Heart Journal
|December 1, 1995
PubMed

Insights

Platelet and leukocyte activation persist for 6 months post-myocardial infarction, suggesting ongoing atherosclerosis. Enalapril showed minimal impact on these inflammatory markers.

Area of Science:

  • Cardiology
  • Immunology
  • Biochemistry

Background:

  • Acute myocardial infarction (AMI) triggers inflammatory responses.
  • Persistent inflammation post-AMI may indicate ongoing atherosclerotic processes.
  • Understanding these reactivities is crucial for patient management.

Purpose of the Study:

  • To investigate the temporal patterns of platelet and leukocyte activation after AMI.
  • To evaluate the effect of enalapril on these inflammatory markers.
  • To determine if persistent activation correlates with ongoing atherosclerosis.

Main Methods:

  • Double-blind, placebo-controlled study involving 74 patients post-AMI.
  • Measurements of fibrinogen, leukocytes, elastase, B beta 30-43 peptide, and platelet angiotensin converting enzyme activity at multiple time points (0-180 days).
  • Comparison of enalapril group versus placebo group.

Main Results:

  • Platelet and leukocyte activation were observed within the first 7 days post-AMI.
  • Fibrinogen, leukocytes, elastase, and B beta 30-43 remained elevated in a significant proportion of patients for 6 months.
  • Enalapril did not significantly alter fibrinogen, leukocyte count, or elastase levels; B beta 30-43 peptide showed a decrease but without significant group difference compared to placebo.
  • No detectable angiotensin converting enzyme activity in platelets was found.

Conclusions:

  • Platelet activation is transient (first week post-AMI), while fibrinogen and leukocyte activation persist for 6 months.
  • Persistent inflammatory markers suggest an ongoing atherosclerotic process after AMI.
  • Enalapril demonstrated limited efficacy in modulating these specific inflammatory reactivities in the post-AMI period.

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