Bioenergetic Effect of Pioglitazone in CLD-PH

This study is testing whether pioglitazone — a diabetes medication — can improve how the heart and lungs use energy in people with pulmonary hypertension caused by chronic lung disease (CLD-PH). This type of high blood pressure in the lungs is difficult to treat, and researchers hope this drug may help. **You may be eligible if...** - You have been diagnosed with pulmonary hypertension caused by chronic lung disease, confirmed by a right heart catheterization - Your pulmonary hypertension meets specific pressure and resistance criteria from the catheter test - You are on stable doses of any approved pulmonary hypertension medications - You are willing and able to take oral medication and follow study procedures **You may NOT be eligible if...** - You have pulmonary hypertension caused by something other than chronic lung disease (e.g., heart failure or blood clots) - You have certain other serious conditions that would make pioglitazone unsafe - You are pregnant or planning pregnancy Talk to your doctor to see if this trial is right for you.