Inclusion Criteria:

• 1. Signed and dated IRB approved study consent form prior to study related procedures
• 2. ≥ 18 years old
• 3. Chronic symptomatic Heart Failure (HF) documented by the following:
• 1. NYHA class II with a history of NYHA class \> II; NYHA class III; or ambulatory NYHA class IV AND
• 2. ≥ 1 HF hospital admission (with HF as the primary, or secondary diagnosis); or treatment with intravenous (IV) or intensification of oral diuresis for HF in a healthcare facility (emergency department/acute care facility) within the 12 months prior to study entry; OR an NT-pro BNP value \> 150 pg./ml in normal sinus rhythm, \> 450 pg./ml in atrial fibrillation, or a BNP value \> 50 pg./ml in normal sinus rhythm, \> 150 pg./ml in atrial fibrillation within the past 6 months prior to study entry.
• 4. In the judgment of the investigator, subject is on stable Guideline Directed Medical Therapy (GDMT) for heart failure and management of potential comorbidities according to current ACCF/AHA Guidelines and that is expected to be maintained without change for 3 months
• 5. At rest: elevated LAP or PCWP pressure of \> 15 mmHg and LAP (or PCWP) exceeds right atrial pressure (RAP) by \> 5 mmHg AND/OR during supine ergometer exercise stress test, as measured at end-expiration, elevated LA (or PCWP) pressure of \> 25 mmHg and LA (or PCWP) exceeds right atrial pressure (RAP) by \> 10 mmHg
• 6. Willing to attend study follow-up assessments for up to 5 years
• Inclusion Criteria for Cohort B, Heart Failure with Pulmonary Vascular Disease only:
• 1. Pulmonary Vascular Resistance (PVR) \> 3.0 and ≤ 8.0 Wood Units at rest
• 2. Mean Pulmonary Artery Pressure (mPAP) ≥ 25 mmHg at rest AND
• 3. If baseline PVR is \> 4.0, must show successful reversibility of PH under a resting Sodium Nitroprusside\* challenge where success is defined as a lowering of the PVR to a level ≤ 4.0 Wood Units while maintaining a Systolic Blood Pressure ≥ 90 mmHg.
• * Equivalent vasodilator agent (e.g., nitric oxide) may be used as deemed appropriate per hospital practice

Exclusion Criteria:

• 1. Severe heart failure defined as one or more of the below:
• 1. ACC/AHA/ESC Stage D heart failure, non-ambulatory NYHA Class IV HF
• 2. If BMI \< 30, Cardiac index \< 2.0 L/min/m2
• 3. If BMI ≥ 30, cardiac index \< 1.8 L/min/m2
• 4. Inotropic infusion (continuous or intermittent) within the past 6 months
• 5. Patient is on the cardiac transplant waiting list
• 6. LVEF \< 20%
• 2. Presence of significant valve disease defined by the site cardiologist as:
• 1. Mitral valve regurgitation defined as grade \> 3+ MR or \> moderate MS
• 2. Tricuspid valve regurgitation defined as grade \> 2+ TR
• 3. Aortic valve disease defined as \> 2+ AR or \> moderate AS
• 3. MI and/or any therapeutic invasive, non-valvular cardiac procedure within past 3 months or current indication for coronary revascularization
• 4. Surgical valve repair or replacement within the past 12 months; Transcatheter valve repair or replacement within the past 6 months.
• 5. Cardiac Resynchronization Therapy initiated, stroke or transient ischemic attack (TIA) within the past 6 months
• 6. Hemodynamic instability within 30 days of scheduled implant procedure
• 7. Patient requiring surgery under general anesthesia for any reason within 30 days of scheduled implant procedure
• 8. Clinically diagnosed hypertrophic obstructive cardiomyopathy, constrictive pericarditis or other infiltrative cardiomyopathy (eg, hemochromatosis, sarcoidosis)
• 9. Has renal insufficiency as determined by creatinine (S-Cr) level \> 2.5 mg/dL or estimated-GFR \< 25ml/min/1.73 m2 by CKD-Epi equation; or currently requiring dialysis
• 10. Significant hepatic impairment defined as 3× upper limit of normal of transaminases, total bilirubin, or alkaline phosphatase
• 11. Performance of the 6 minute walk test with a distance \<50m OR \>600m
• 12. Subject is contraindicated to receive either dual antiplatelet therapy or warfarin (analogue); or has a documented coagulopathy
• 13. Known hypersensitivity to anticoagulation therapy or contrast agent, which cannot be adequately medicated
• 14. Known hypersensitivity to Nickel and/or Tantalum
• 15. In the judgment of the investigator, life expectancy \<12 months for noncardiovascular reasons
• 16. In the opinion of the investigator, the subject is not an appropriate candidate for the study
• 17. Anatomy (including implantable devices) that is not compatible with the Edwards Transcatheter Atrial Shunt System
• 18. Active endocarditis or infection within 3 months of scheduled implant procedure
• 19. Currently participating (e.g., undergoing trial specific exams/treatment/procedures) in an investigational drug or device study. Note: trials requiring extended follow-up for products that were investigational but have since become commercially available are not considered investigational trials.
• 20. Patient is a current intravenous recreational drug user
• 21. Positive serum pregnancy test in female subjects of child-bearing potential or nursing mothers or planning on becoming pregnant during the duration of the trial
• 22. Patient is under guardianship
• 23. Known pre-existing shunting, determined to be clinically significant by the investigator
• 24. (Not applicable to Cohort B) Right ventricular dysfunction, defined by the site cardiologist as:
• 1. More than mild RV dysfunction as estimated by TTE; OR
• 2. TAPSE \<1.4 cm; OR
• 3. RV size ≥ LV size as estimated by TTE; OR
• 4. Echocardiographic or clinical evidence of congestive hepatopathy
• 25. Evidence of pulmonary vascular disease with PVR \>3.0 Wood units
• Exclusion Criteria for Cohort B, Heart Failure with Pulmonary Vascular Disease only:
• 1. Propensity for increased Right ventricular dysfunction, defined by the site cardiologist as:
• 1. More than moderate RV dysfunction as estimated by TTE; OR
• 2. TAPSE \<1.2 cm; OR
• 3. RV size ≥ LV size as estimated by TTE; OR
• 4. Mean Right Atrial Pressure (RAP) \> 18 mm Hg; OR
• 5. Echocardiographic or clinical evidence of congestive hepatopathy