4. Patient is on the cardiac transplant waiting list 4. Inability to perform 6 Minute Walk Test 5. Known significant coronary artery disease (stenosis >70%) 6. History of stroke, transient ischemic attack (TIA), deep vein thrombosis (DVT), or pulmonary emboli within the past 6 months 7. Known severe carotid artery stenosis (> 70%) 8. Presence of significant valve disease defined by echocardiography as: a) Mitral valve regurgitation defined as grade >2+ MR b) Tricuspid valve regurgitation defined as grade ≥ 2+ TR; c) Aortic valve disease defined as ≥ 2+ AR or moderate AS