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.