129Xe MRI Cardiopulmonary

This study is using a special type of MRI that uses inhaled xenon-129 gas to take detailed pictures of the lungs and heart. Researchers want to understand how breathing and blood flow in the lungs differ between healthy people and those with certain medical conditions. **You may be eligible if (healthy volunteer)...** - You are 18 or older with no diagnosed lung conditions - You have not smoked in the past 5 years and have less than 5 pack-years of smoking history - You have not regularly used inhaled products (like e-cigarettes) **You may be eligible if (patient)...** - You are 18 or older and have a condition such as heart failure, sickle cell disease, lung disease, or are undergoing blood transfusion or phlebotomy **You may NOT be eligible if...** - You have active infections or contraindications to MRI - You are pregnant or breastfeeding Talk to your doctor to see if this trial is right for you.