Background Increased serum osteoprotegerin has been shown to be associated with increased mortality and heart failure development in patients with acute coronary syndromes. The aim of the present study was to elucidate a possible association between serum osteoprotegerin measured acutely in patients with ST-elevation myocardial infarction (STEMI) and final infarct size.

Methods Serum osteoprotegerin was measured in fasting blood samples from 199 patients with acute STEMI, sampled at a median time of 16 h after primary percutaneous coronary intervention (PCI). After 3 months, final infarct size (in percentage of left ventricular mass; LVM) was assessed by single-photon emission CT. The outcome variable final infarct size was dichotomised using the 75th percentile as the cutoff value (large infarct size ≥29.0%). A multivariable analysis was performed adjusting for multiple clinical and biochemical covariates.

Results Median (IQR) osteoprotegerin concentration was 1.4 (1.0, 2.1) ng ml⁻¹ and patients with high osteoprotegerin level (> median) at baseline had larger infarct size at 3 months compared with patients with low osteoprotegerin levels (< median) (25 (8, 40) vs 6 (0, 19)% of LVM, respectively, p<0.0001). A high osteoprotegerin level was also associated with an approximately sevenfold increase in the odds of developing a large myocardial infarct (OR 7.0; 3.2, 15.5, p<0.001). After adjustment for potential confounders including peak troponin T, the adjusted OR was 5.2 (2.0, 13.1) p<0.001.

Conclusion High levels of circulating osteoprotegerin measured the first morning after a PCI-treated acute STEMI were strongly associated with final infarct size.