CardioMEMS Heart Sensor Allows Monitoring of Pressure to Improve Outcomes in NYHA Class III Heart Failure Patients

Inclusion Criteria: 1. Diagnosis of HF ≥ 3 months, with either preserved or reduced LVEF 2. Diagnosis of NYHA Class III HF (historical assessment documented at screening visit) 3. Subjects with reduced LVEF must be receiving a beta blocker for 3 months and an ACE-I or ARB for one month unless in the investigator's opinion, the subject is intolerant to beta blockers, ACE-I or ARB. Beta blockers and ACE-I (or ARB) doses should be stable for one month prior to study entry. 4. At least 1 HF hospitalization within 12 months of Screening Visit 5. Subjects with pulmonary artery branch diameter sized between 7mm and 15mm (implanted vessel) Exclusion Criteria: 1. Subjects with history of recurrent (\> 1) pulmonary embolism or deep vein thrombosis 2. Subjects, in the Investigator's opinion, unable to tolerate a right heart catheterization 3. Subjects who have had a major cardiovascular event (e.g., myocardial infarction, stroke) within 2 months of Screening Visit 4. Subjects with Cardiac Resynchronization Device (CRT) implanted ≤ 3 months prior to enrollment 5. Subjects with a Glomerular Filtration Rate (GFR) \<25 ml/min who are non-responsive to diuretic therapy or who are on chronic renal dialysis 6. Subjects likely to undergo heart transplantation within 6 months of Screening Visit 7. Subjects with congenital heart disease or mechanical right heart valve(s) 8. Subjects with known coagulation disorders 9. Subjects with a hypersensitivity or allergy to aspirin, and/or clopidogrel