Local Matrix Metalloproteinase 9 Level Determines Early Clinical Presentation of ST-Segment-Elevation Myocardial...

Area of Science:

• Cardiology
• Biochemistry
• Pathophysiology

Background:

• Early clinical presentation of myocardial infarction (MI), including ST-segment-elevation MI (STEMI) and non-ST-segment-elevation MI (NSTEMI), significantly impacts patient management.
• While local inflammatory processes are implicated in MI onset, their specific influence on early clinical presentation remains incompletely understood.

Purpose of the Study:

• This study aimed to investigate the relationship between local inflammatory activities and the early clinical presentation of MI.
• Specifically, it sought to determine if local inflammatory markers could predict STEMI versus NSTEMI presentation.

Main Methods:

• The study included 94 MI patients (69 STEMI, 25 NSTEMI) and 17 with stable angina.
• Culprit lesion morphologies were assessed using optical coherence tomography.
• Local and systemic inflammatory markers, including matrix metalloproteinase 9 (MMP-9) and myeloperoxidase, were measured before and after stenting.

Main Results:

• Patients with STEMI and NSTEMI exhibited higher prevalence of plaque rupture, thin-cap fibroatheroma, and lipid arc/macrophage count compared to stable angina patients.
• Red thrombus was more frequent in STEMI.
• Local MMP-9 levels were significantly higher than systemic levels, with post-stent local MMP-9 markedly elevated in STEMI patients.
• Post-stent local MMP-9 and red thrombus presence independently determined STEMI in multivariate analysis.

Conclusions:

• Local matrix metalloproteinase 9 (MMP-9) levels are significant determinants of early clinical presentation in myocardial infarction (MI).
• Increased attention to local inflammatory activity in atherosclerosis is warranted for improved patient stratification and management.
• These findings highlight the potential of MMP-9 as a biomarker for differentiating MI subtypes early on.