Chronic Thromboembolic Pulmonary Hypertension After Pulmonary Embolism

This study follows patients who have had a blood clot in the lungs (acute pulmonary embolism) to see which ones go on to develop a chronic condition called chronic thromboembolic pulmonary hypertension (CTEPH) — high blood pressure in the lung arteries due to old clots. Early detection of CTEPH can improve long-term outcomes. **You may be eligible if...** - You have been diagnosed with acute pulmonary embolism (blood clot in the lung) - You are between 18 and 80 years old - Your pulmonary embolism was classified as moderate to high severity (PESI class III-V or sPESI score of 1 or more) **You may NOT be eligible if...** - You have a known secondary cause of pulmonary hypertension not related to blood clots - You have severe kidney disease - You have significant liver disease - You have a reason why you cannot take blood thinners (anticoagulation) Talk to your doctor to see if this trial is right for you.