MIF- Thyroxine Interactions in the Pathogenesis of Pulmonary Arterial Hypertension

The investigators will test our hypothesis and accomplish our objectives by pursuing three Specific Aims:

To investigate the interrelationship between macrophage migration inhibitory factor (MIF) and free T4 in patients with PAH with a working hypothesis that an increased release of MIF into the pulmonary vasculature during cardiopulmonary exercise changes the normal balance between plasma MIF and T4.

Inclusion criteria

• Subject must be at least 18 years of age and have confirmed pulmonary hypertension (PH) and interstitial lung disease (ILD).
• ILD was identified on high resolution computed tomography along with a total lung capacity (TLC) <70% of predicted value on pulmonary function tests (PFTs) with no evidence of pulmonary hypertension on echocardiogram.
• PAH group patients were defined as patients with a mean pulmonary artery pressure >25 mmHg at rest and a wedge pressure of <15 mmHg (millimeters of mercury), measured by right heart catheterization (WHO group I PAH).
• PH+ILD group, subjects with evidence of ILD on high resolution CT Scan and mean pulmonary artery pressure >25 mmHg on right heart catheterization.
• Patient with evidence of Chronic thromboembolic disease on CT angiogram and mean pulmonary artery pressure >25mmHg on right heart catheterization. (WHO group IV)
• Patient with Pulmonary Hypertension due to other conditions, such as Sarcoidosis, Gauchers disease, Hemolytic Anemia and Myeloproliferative disorders.
• Normal control group: Subjects without cardiopulmonary disease, with a normal PFT and ECG.

Exclusion criteria

• Failure to obtain informed consent;
• Pregnancy
• Subjects with cardiopulmonary disease other than PH and ILD;
• Unexplained abnormal PFT, ECG, Routine blood/chemistries test
• History or existing other sever organ/system diseases
• Defined Acute pulmonary embolism
• Age < 18 years