TNF and chronic thromboembolic pulmonary hypertension: Tumor Necrosis Factor-alpha (TNF-α) is an inflammatory cytokine thatwas upregulated in the blood of CTEPH patients as compared to the control groups.It has been reported that increasing levels of TNF-αcould indicate the extent of right heart failure associated with CTEPH [5].Though the preoperative TNF-α levels were high, there was no relation tothe preoperative pulmonary hemodynamic status.