Usefulness of serum myeloperoxidase in prediction of mortality in patients with severe heart failure.

BACKGROUND Myeloperoxidase levels were shown to reflect endothelial dysfunction, inflammation, atherosclerosis and oxidative stress. OBJECTIVES To examine the role of circulating myeloperoxidase, a leukocyte-derived enzyme, as a predictor of mortality in patients with congestive heart failure. METHODS Baseline serum MPO levels were measured in 285 consecutive CHF patients and 35 healthy volunteers. N-terminal pro-brain natriuretic peptide and high sensitivity C-reactive protein concentrations were also measured. The primary outcome endpoint was overall mortality. RESULTS MPO levels were significantly elevated in patients with CHF compared to healthy volunteers (P = 0.01). During a mean follow-up of 40.9 +/- 11.3 months there were 106 deaths. On a univariate Cox regression analysis MPO levels were of marginal value (P = 0.07) whereas NT-proBNP was of considerable value (P < 0.0001) in predicting all-cause mortality. By dividing our cohort according to NT-proBNP levels into high, intermediate and low risk groups a clear difference in mortality was shown. By further dividing the patient cohort according to MPO levels above or below the median (122.5 ng/ml), mortality prediction improved in the patients with intermediate NT-proBNP values. CONCLUSIONS MPO levels are elevated in CHF and correlate with disease severity. MPO has an additive predictive value on mortality in patients with intermediate NT-proBNP levels.