We studied 49 patients with CTEPH (50 ± 2 years, right ventricular ejection fraction [RVEF] 29 ± 2 % , left ventricular ejection fraction [LVEF] 51 ± 3 % , mean ± SEM) and compared their results with 17 patients with CHF (71 ± 2 years, LVEF 23 ± 1 % ) and 34 age-matched control subjects (age 57 ± 2 years). We studied serum levels of tumor necrosis factor-α (TNFα), its soluble receptors 1 and 2 (sTNFR1 and 2), interleukin-10 (IL-10) and plasma N-terminal-pro-B-type natriuretic peptide (NT-proBNP). Serum TNFα was not different in CTEPH compared with CHF patients (p = 0.67) but both their levels were significantly higher than in controls (both p < 0.001). Similar results were obtained for sTNFR1, sTNFR2, and IL-10. Levels of NT-proBNP were not different in patients with CTEPH or CHF (p = 0.54), but significantly higher than in control subjects (both p < 0.001). There were significant correlations between RVEF as assessed by magnetic resonance imaging and sTNFR1, sTNFR2, IL-6, high sensitivity C-reactive protein, and NT-proBNP (all p < 0.05) in patients with CTEPH.
Similar levels of immune activation as reflected by high levels of pro-inflammatory cytokines are present in patients with isolated right ventricular dysfunction due to CTEPH and patients with CHF and left ventricular dysfunction.