Inflammatory markers are elevated in Eisenmenger syndrome

Abstract

Inflammation may be an important contributing factor to the progression of Eisenmenger syndrome (ES). Markers of systemic inflammation in ES have not been systematically studied. Inflammatory markers including high-sensitivity C-reactive protein (hs-CRP), interleukin-2 (IL-2), IL-6, and interferon-γ (IFN-γ) were measured in 42 consecutive ES patients (mean age, 24.3 ± 10.6 years) compared with their levels in 22 healthy control subjects. The patients were followed up for a mean duration of 16.3 ± 13.7 months. The levels of inflammatory markers were correlated with clinical and hemodynamic variables at baseline and the outcomes of death, hospitalization, and worsening World Health Organization (WHO) functional class at follow-up evaluation. Compared with the control subjects, ES patients showed a significant elevation in hs-CRP (2.99 ± 3.5 vs 1.1 ± 0.9 mg/dl; p = 0.002) and IFN-γ (41.3 ± 43.6 vs 10.4 ± 6.9 pg/ml; p < 0.001) levels. The levels of IL-2 and IL-6 also were elevated but did not differ significantly from those in the control subjects. The patients with hs-CRP levels higher than 3 mg/dl were significantly older (28.9 ± 10.6 vs 21.5 ± 9.8 years) and had a significantly shorter 6-min walk distance (421.5 ± 133.2 vs 493.3 ± 74.8 m). The levels of inflammatory markers did not correlate with baseline parameters or clinical outcomes. To conclude, the levels of hs-CRP and IFN-γ are significantly elevated in ES. Elevated hs-CRP in ES was associated with older age and shorter 6-min walk distance, but the levels of inflammatory markers were not predictive of clinical events.