Prognostic Value of SIRI in ACS Patients Undergoing Primary PCI: Meta-Analysis

Overview

This systematic review and meta-analysis evaluated the prognostic significance of the systemic inflammatory response index (SIRI) in patients with acute coronary syndrome (ACS) undergoing primary percutaneous coronary intervention (PCI). Elevated SIRI levels were associated with increased risk of all-cause mortality and major adverse cardiovascular events (MACE), supporting its role as a valuable biomarker for risk stratification post-PCI.

Background

Acute coronary syndromes (ACS) are a leading cause of morbidity worldwide, with percutaneous coronary intervention (PCI) as the standard treatment to reduce adverse cardiovascular events. Despite advances, residual risk of recurrent events remains high, necessitating reliable prognostic biomarkers. Inflammation plays a key role in the pathophysiology of coronary artery disease, influencing infarct expansion, remodeling, and recurrent ischemic risk. The systemic inflammatory response index (SIRI), derived from neutrophil, monocyte, and lymphocyte counts, reflects the balance between pro-inflammatory and anti-inflammatory responses and has emerged as a potential prognostic marker in cardiovascular disease.

Data Highlights

The meta-analysis included cohort studies assessing SIRI in ACS patients treated with primary PCI. Outcomes analyzed were all-cause mortality, major adverse cardiovascular events (MACE), new acute myocardial infarction, revascularization, and stroke. Hazard ratios (HR) or odds ratios (OR) with 95% confidence intervals (CI) were extracted or calculated to quantify associations.

Key Findings

• Elevated SIRI was significantly associated with increased all-cause mortality in ACS patients post-primary PCI.
• Higher SIRI levels predicted a greater risk of major adverse cardiovascular events (MACE) following PCI.
• SIRI demonstrated prognostic value beyond traditional risk factors, reflecting the impact of systemic inflammation on outcomes.
• The index integrates neutrophil, monocyte, and lymphocyte counts, capturing both pro-inflammatory and immune status relevant to CAD progression.
• Use of SIRI may facilitate identification of high-risk patients who could benefit from intensified monitoring and tailored therapeutic strategies.

Clinical Implications

SIRI is a readily available, cost-effective biomarker that can enhance risk stratification in ACS patients undergoing primary PCI. Incorporating SIRI into clinical practice may improve individualized patient management by identifying those at higher risk for mortality and adverse events, potentially guiding anti-inflammatory or other adjunctive therapies. Further prospective studies are warranted to validate its utility and integrate it into standardized prognostic models.

Conclusion

This meta-analysis supports the prognostic significance of SIRI in ACS patients treated with primary PCI, highlighting its potential as a novel inflammatory biomarker for improving post-intervention risk assessment and guiding clinical decision-making.

References

1. Li et al. 2025 -- Evaluating the Prognostic Significance of the Systemic Inflammatory Response Index (SIRI) in Patients with Acute Coronary Syndrome Undergoing Primary Percutaneous Coronary Intervention: A Systematic Review and Meta-Analysis