Abstract 11910: The Systemic Inflammatory Response Syndrome is associated with Worse Outcomes in ST-Elevation Myocardial Infarction Patients: Insights from the CARDINAL Trial

Abstract

Background: The systemic inflammatory response syndrome (SIRS) is an adverse prognostic marker in several medical and surgical conditions. Whether SIRS is associated with morbidity and mortality in ST-segment elevation myocardial infarction (STEMI) is unclear.

Methods: In the CARDINAL project the incidence of SIRS was described in the 1186 patients with data available for all SIRS criteria. Using multiple imputation for the 1848 patients with available endpoints, we compared the 90-day incidence of death, shock, heart failure, or stroke between patients with and without SIRS at presentation and 24 hours post-admission. SIRS was defined as ≥2 of: 1) heart rate >90 beats/min, 2) respiratory rate >20 breaths/min, 3) body temperature >38 or <36°C, or 4) leukocyte count >12 or <4 x 10⁹/L.

Results: At presentation, 25.0% of patients met SIRS criteria; at 24 hours, 8.1% met SIRS criteria. The primary outcome was more frequent among patients with SIRS at presentation (31.0% vs 16.7%; adjusted hazard ratio [adj HR] 1.78, 95% Confidence Interval [CI], 1.35 to 2.34; p<0.001) and 24 hours (36.7% vs 11.1%; adj HR 1.97, 95% CI 1.73 to 2.24; p<0.001). 90-day mortality was also higher among SIRS patients at presentation (10.1% vs 6.1%, p=0.018) and at 24 hours (8.7% vs 3.9%; p=0.052). Each additional SIRS criterion was independently associated with 90 day outcomes at the time of presentation (adj HR 1.41 per SIRS criteria: 95% CI, 1.24 to 1.61; p<0.001, Figure) and 24 hours (adj HR 1.72 per SIRS criteria: 95% CI, 1.47 to 2.01; p<0.001).

Conclusion: The diagnosis of SIRS and cumulative number of SIRS criteria were independently associated with 90-day clinical outcomes among STEMI patients. The independent association of this simple composite measure of inflammatory response with outcomes underscores the importance of the clinical inflammatory response in STEMI and identifies the need for specific strategies to strategies to address this high risk STEMI subset.