Additional Study Information: This research study is being conducted to study pulmonary hypertension and right heart dysfunction based on clinical, imaging, physiological and pathological characteristics. We hope to develop a new classification system and new methods to diagnose and treat pulmonary hypertension. Diagnostic testing includes (listed subsequently): full medical work-up, minimal blood collection, right heart catheterization, echocardiogram, ekg, take home sleep oximetry study, six-minute walk, exercise test, Pulmonary function test, Lung CT, Questionnaires, ventilation/perfusion scan and cardiac MRI.