Association of Soluble IL-1 Receptor Type 2 with Recovery of Left Ventricular Function and Clinical Outcomes in Acute Myocardial Infarction

Background: The role of soluble interleukin-1 receptor type 2 (sIL-1R2) in acute myocardial infarction (AMI) remains undocumented. In the present study, we aimed to evaluate the possible associations of sIL-1R2 with left ventricular (LV) function, remodeling and future clinical events in the setting of AMI.

Methods: Circulating sIL-1R2 levels were quantified after percutaneous coronary intervention (PCI) on day 1 of hospital admission for 204 AMI patients, and upon enrollment of 204 healthy controls. Echocardiography was conducted in the acute phase and at 12-month follow-up. Adverse clinical events were registered after 12 months.

Results: Circulating sIL-1R2 levels were significantly higher in AMI patients than in healthy controls (medians respectively 6652.81 pg/mL, 3799.13 pg/mL, p $<$ 0.0001). AMI patients with sIL-1R2 levels less than the median had a larger proportion of worsened LV ejection fraction [a decrease in LV ejection fraction (LVEF) of more than 10% units] and reduced LVEF (a final LVEF $<$ 50%). After multivariate adjustment, sIL-1R2 levels less than the median were associated with an increased risk of worsened LVEF [odds ratio (OR): 3.7, 95% confidence interval (CI): 1.6-8.5, p = 0.002] and reduced LVEF at 12 months (OR: 2.1, 95% CI: 1.1-4.3, p = 0.035). Moreover, low sIL-1R2 levels were associated with an increased risk of having an adverse clinical event during the first 12 months after AMI [hazard ratio (HR): 2.5, 95% CI: 1.0-6.1, p = 0.039].

Conclusions: Low levels of circulating sIL-1R2 were associated with impaired recovery of LV function and adverse clinical outcomes in AMI patients. These findings might contribute to understanding the important role of sIL-1R2 in postinfarction inflammation.