Quantifying 18kDa TSPO Expression in the Lung in Pulmonary Artery Hypertension (PAH)

This study is using a special type of brain/body scan (called a PET scan with a radioactive tracer) to measure a specific protein in the lungs of people with pulmonary arterial hypertension (PAH), a condition where blood pressure in the lungs is abnormally high. Researchers hope this will help better understand and diagnose PAH. **You may be eligible if...** - You have pulmonary arterial hypertension (PAH) - You are able to lie still on your back for up to 90 minutes - You can provide written informed consent in English - Women of childbearing age must use effective contraception and have a negative pregnancy test **You may NOT be eligible if...** - You have a specific genetic variant (TT genotype at rs6971) that affects the scan tracer - You have significant kidney or liver disease - You have severe anemia, sickle cell disease, or thalassemia - You have uncontrolled high blood pressure - You have a current infection, HIV, or chronic inflammatory disease including hepatitis B - You are pregnant or breastfeeding - You have participated in another drug study recently Talk to your doctor to see if this trial is right for you.