Osteoprotegerin levels change during STEMI and reflect cardiac function

Abstract

Background: High levels of circulating osteoprotegerin (OPG) predicts long-term outcome in patients with ST-elevation myocardial infarction (STEMI), possibly because of increased vascular inflammation resulting in myocardial damage. In the present study we aimed at elucidating the dynamic progress of OPG levels during STEMI treated with percutaneous coronary intervention (PCI) and additionally, the effect of OPG levels on cardiac function.

Methods: We prospectively included 42 patients with STEMI treated with primary PCI. Four consecutive blood samples were obtained before and after PCI treatment. Plasma OPG levels were determined using an in-house immunoassay. Cardiac function was increased according to echocardiography, estimating left ventricular ejection fraction (LVEF) 1-3 days after STEMI.

Results: During STEMI, OPG levels peaked after PCI and then decreased; mean concentrations (95% confidence interval) before PCI, after PCI, and on day 1 and day 2 of 2650 ng/L (2315-3036 ng/L), 2778 ng/L (2442-3363 ng/L), 2024 ng/L (1775-230 6 ng/L), and 1808 ng/L (1551-2106 ng/L), respectively (P < 0.001). Interestingly, the OPG response was observed before the response in troponin I and C-reactive protein. Patients with reduced LVEF (< 40%) exhibited an increased OPG response before, during, and after PCI (mean increase, 38%; 9%-75%; repeated measures analysis of variance, P = 0.009). Adjustment for age, sex, body mass index, and cardiovascular risk factors did not significantly affect the association between reduced LVEF and increased OPG response (mean increase 33% (4%-70%; F = 5.784; P = 0.023).

Conclusions: Circulating OPG levels are altered during STEMI treated with primary PCI. A high OPG level is independently associated with impaired LVEF.