Plasma myeloperoxidase levels in patients with chronic heart failure.

Increased oxidative stress and endothelial dysfunction are commonly observed in patients with chronic heart failure (HF). The relation between myeloperoxidase (MPO), an inflammatory marker with mechanistic links to plaque vulnerability and abnormal ventricular remodeling, and degrees of severity in chronic HF has not been reported. Plasma MPO levels were measured in 105 normal controls (no history of HF or left ventricular dysfunction) and 102 patients with chronic systolic HF (left ventricular ejection fraction <50%), and the relations among plasma MPO levels, plasma B-type natriuretic peptide levels, and the left ventricular ejection fraction were examined. Plasma MPO levels in patients with chronic systolic HF were significantly elevated compared with those of healthy controls (1,158 +/- 2,965 vs 204 +/- 139 pM, p <0.0001). Plasma MPO levels increased in parallel with increasing New York Heart Association class (p <0.0001) and were correlated with plasma B-type natriuretic peptide levels (Spearman's r = 0.39, p <0.0001). Levels of MPO were strongly associated with the prevalence of HF (unadjusted odds ratio 30.3, 95% confidence interval 11.1 to 94.5) and remained significant when adjusted for age and B-type natriuretic peptide (odds ratio 27.7, 95% confidence interval 3.6 to 371.1). In conclusion, in a cohort of patients with chronic HF, plasma MPO levels were elevated compared with those of normal controls and were associated with worsening functional class.