Plasma lipoprotein-associated phospholipase A2 mass is elevated in STEMI compared to non-STEMI patients but does not discriminate between myocardial infarction and non-cardiac chest pain

Background: Plasma lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) mass predicts future cardiovascular events in the non-acute setting. We tested the extent to which Lp-PLA(2) is elevated in patients with acute coronary syndrome. Methods: A total of 231 consecutive patients referred for acute chest pain participated. Of this number, 144 were diagnosed with myocardial infarction (MI; 100 were classified as MI with ST-elevation (STEMI) and 44 as MI without ST-elevation (non-STEMI)). Eighty-seven patients had non-cardiac chest pain. Plasma Lp-PLA(2) mass was measured using turbidimetric immunoassay. Results: Lp-PLA(2) mass was not different between MI patients and patients with non-cardiac chest pain (231 +/- 72 mu g/l vs.243 +/- 88 mu g/l, p = 0.29), and did not relate to MI in age- and sex-adjusted logistic regression analysis (odds ratio per SD increment, 0.92 (95% CI, 0.69-123), p = 0.58). However, Lp-PLA(2) mass was elevated in STEMI compared to non-STEMI patients (246 +/- 73 vs. 198 +/- 58 ng/ml, p < 0.001), and independently predicted STEMI (odds ratio, 2.35 (95% CI, 1.46-3.79),p < 0.001). Among MI patients maximal creatine kinase was correlated positively with Lp-PLA(2) (r = 0.183, p = 0.034). Conclusions: In the acute setting, plasma Lp-PLA(2) mass is not elevated in MI patients, although Lp-PLA(2) mass appears to relate to the severity of myocardial damage. (c) 2013 Elsevier B.V. All rights reserved.