Effects of alirocumab on endothelial function and coronary atherosclerosis in myocardial infarction: A PACMAN-AMI

Emrush Rexhaj1, Sarah Bär1, Rodrigo Soria1

  • 1Department of Cardiology, Bern University Hospital Inselspital, Freiburgstrasse 18, 3010, Bern, Switzerland.

Atherosclerosis
|March 21, 2024
PubMed

Insights

Adding alirocumab to high-intensity statin therapy did not improve endothelial function (FMD) in acute myocardial infarction patients. FMD correlated with baseline plaque burden but not lipid pool or fibrous cap thickness.

Area of Science:

  • Cardiology
  • Vascular Biology
  • Pharmacology

Background:

  • Endothelial function, assessed by flow-mediated dilation (FMD), is crucial in cardiovascular health.
  • The impact of protein convertase subtilisin/kexin type 9 (PCSK9) inhibitors on FMD in acute myocardial infarction (AMI) patients remains unclear.
  • High-intensity statin therapy is a cornerstone of secondary prevention after AMI.

Purpose of the Study:

  • To investigate the effect of the PCSK9 inhibitor alirocumab, added to high-intensity statin, on FMD in AMI patients.
  • To explore the association between FMD and coronary atherosclerosis in non-infarct related arteries.
  • To utilize advanced intracoronary imaging techniques (IVUS, NIRS, OCT) for detailed plaque analysis.

Main Methods:

  • A substudy of the randomized-controlled PACMAN-AMI trial involving patients treated with alirocumab or placebo plus rosuvastatin.
  • Brachial artery FMD measurements at 4 and 52 weeks.
  • Intracoronary imaging (IVUS, NIRS, OCT) performed at baseline and 52 weeks for plaque characterization.

Main Results:

  • No significant difference in FMD at 52 weeks between the alirocumab and placebo groups (5.44% vs. 5.45%).
  • FMD significantly improved over 52 weeks in both groups.
  • Early FMD (4 weeks) was associated with baseline plaque burden (IVUS) but not with lipid pool (NIRS) or fibrous cap thickness (OCT).

Conclusions:

  • In AMI patients, adding alirocumab to high-intensity statin therapy did not enhance FMD compared to statin therapy alone.
  • FMD is linked to the overall burden of coronary plaque but not specifically to lipid content or fibrous cap stability.
  • These findings suggest that PCSK9 inhibition may not directly improve endothelial function in this patient population beyond standard statin therapy.
Abstract