A Prospective, Multi-Center, Open Label, Single Arm Clinical Trial Evaluating the Safety and Efficacy of the Cordella™ Pulmonary Artery Sensor System in New York Heart Association (NYHA) Class III Heart Failure Patients (PROACTIVE- HF Trial)

Inclusion Criteria 1. Subject has given written informed consent 2. Male or female, at least 18 years of age 3. Diagnosis and treatment of HF (regardless of left ventricular ejection fraction (LVEF)) for ≥ 3 months and NYHA Class III HF at time of Screening 4. Subjects should be on stable, optimally titrated medical therapy for at least 30 days, as recommended according to current American Heart Association (AHA)/American College of Cardiology (ACC) guidelines as standard-of-care for HF therapy in the United States, or current European Society of Cardiology (ESC) guidelines for HF treatment in Europe, with any intolerance documented. 5. HF related hospitalization, HF treatment in a hospital day-care setting, or urgent outpatient clinic HF visit for IV diuretics within 12 month (last hospitalization should be 30 days before Screening/Enrollment) and/or N-terminal pro B-type Natriuretic Peptide (NT proBNP) at time of Screening/ Enrollment defined as: 1. Subjects with LVEF ≤ 50%: NT-proBNP ≥ 1500 pg/mL. 2. Subjects with LVEF \> 50%: NT-proBNP ≥ 800 pg/mL . Thresholds for NT-proBNP (for both LVEF ≤ 50% and LVEF \> 50%) will be corrected for body mass index (BMI) using a 4% reduction per BMI unit over 25 kg/m2 6. Subjects should be on diuretic therapy 7. Subjects who are physically able to hold the myCordella™ Patient Reader unit (approximate weight 1.3lb) against the ventral thoracic surface for up to 2 minutes per day while in a seated position, as well as dock and undock the myCordella™ Patient Reader 8. Subjects with sufficient eyesight, hearing, and mental capacity to respond to the myCordella™ Patient Reader's audio/visual cues and operate the myCordella™ Patient Reader 9. Subject has sufficient Cellular and/ or Wi- Fi Internet coverage at home 10. Subject agrees to return to the treating Investigator for all scheduled follow up visits and can return to the hospital for follow up Exclusion Criteria 1. Intolerance to all neuro-hormonal antagonists (i.e., intolerance to ACE-I, ARB, ARNI, and beta-blockers) due to hypotension or renal dysfunction 2. ACC/AHA Stage D refractory HF (including having received or currently receiving pharmacologic circulatory support with inotropes) 3. Subjects with history of recurrent pulmonary embolism ( ≥2 episodes within 5 years prior to Screening Visit) and/or deep vein thrombosis (\< 3 month prior to Screening Visit) 4. Subjects who have had a major cardiovascular (CV) event (e.g. myocardial infarction, stroke) within 3 months of the Screening Visit 5. Unrepaired severe valvular disease 6. Subjects with significant congenital heart disease that has not been repaired and would prevent implantation of the Cordella PA sensor or mechanical/tissue right heart valve(s) 7. Subjects with known coagulation disorders 8. Subjects with a hypersensitivity or allergy to platelet aggregation inhibitors including aspirin, clopidogrel, prasugrel, and ticagrelor; or patients unable to take dual antiplatelet or anticoagulants for one-month post implant 9. Known history of life threatening allergy to contrast dye 10. Subjects whereby RHC is contraindicated 11. Subjects with an active infection at the Sensor Implant Visit 12. Subjects with a Glomerular Filtration Rate (GFR) \<25 ml/min or who are on chronic renal dialysis 13. Implanted with Cardiac Resynchronization Therapy (CRT)-Pacemaker (CRT-P) or CRT-Defibrillator (CRT-D) for less than 90 days prior to screening visit 14. Received or are likely to receive an advanced therapy (e.g. mechanical circulatory support or lung or heart transplant) in the next 12 months 15. Subjects who are pregnant or breastfeeding 16. Subjects who are unwilling or deemed by the Investigator to be unwilling to comply with the study protocol, or subjects with a history of non-compliance 17. Severe illness, other than heart disease, which would limit survival to \<1 year 18. Subjects whose clinical condition, in the opinion of the Investigator, makes them an unsuitable candidate for the study 19. Subjects enrolled in another investigational trial with an active treatment arm 20. Subject who is in custody by order of an authority or a court of law