Prognostic value and echocardiographic determinants of plasma myeloperoxidase levels in chronic heart failure.

OBJECTIVES The purpose of this study was to explore the relationship between myeloperoxidase (MPO) and cardiac structure, performance, and prognosis. BACKGROUND Myeloperoxidase is an inflammatory marker that is elevated in patients with heart failure (HF) and cardiac dysfunction, with mechanistic links to plaque vulnerability and left ventricular (LV) remodeling. METHODS We evaluated plasma MPO levels (CardioMPO, PrognostiX, Inc., Cleveland, Ohio) in 140 patients with chronic systolic HF (LV ejection fraction <35%) and examined the plasma MPO levels' relationships with echocardiographic indexes of systolic and diastolic performance, as well as long-term clinical outcomes (death, cardiac transplantation, or HF hospitalization). RESULTS Within the overall cohort, increasing plasma MPO levels were associated with increasing likelihood of more advanced HF (restrictive diastolic stage, right ventricular systolic dysfunction > or =3+, and tricuspid regurgitation area > or =1.8 cm2). Plasma MPO levels were predictive of long-term clinical outcomes (risk ratio [95% confidence interval] = 3.35 [1.52 to 8.86]), even after adjustment for age, LV ejection fraction, plasma B-type natriuretic peptide (BNP), creatinine clearance, or diastolic stage. In receiver-operator characteristic curve analyses, addition of MPO to BNP testing augmented the predictive accuracy of future adverse clinical events (area under the curve 0.66 for BNP only [chi-square test = 12.9, p = 0.0003], and 0.70 for BNP plus MPO [chi-square test = 15.87, p = 0.0004]). CONCLUSIONS In chronic systolic HF, elevated plasma MPO levels are associated with an increased likelihood of more advanced HF. Moreover, elevated plasma MPO levels within a HF subject seem to be predictive of increased adverse clinical outcomes.