Figure 1. Myeloperoxidase in patients with pulmonary arterial hypertension.

Myeloperoxidase (MPO) accumulates in plasma and lung tissue of patients with pulmonary arterial hypertension (PAH) and is related to increased mortality. (A) Immunohistochemical staining of MPO in lung sections of control subjects and patients with pulmonary hypertension (PH). Representative images of 3 separate individuals per group are displayed. Scale bar: 50 μm. (B) MPO plasma levels in PAH patients at baseline. n = 95; *P < 0.01. Data represent median, with interquartile range and whiskers indicating 5th to 95th percentile. Statistical analysis was performed by Mann-Whitney U test. (C) Kaplan-Meier analysis of survival of PAH patients with MPO plasma levels <583 pmol/l (low) or >583 pmol/l (high). n = 95; χ² = 5.134, P < 0.05. Statistical analysis was performed by log-rank test.