Early Feasibility Study - Edwards APTURE Transcatheter Shunt System

Refined HFrEF Subgroup Inclusion Criteria:

* A primary diagnosis of HFrEF (LVEF ≤ 40%), and
* NYHA Class II, III, or IVa heart failure symptoms and
* Documentation of at least one of the following in the past 12 months, such as:

  * Hospitalization for heart failure; or
  * Increased treatment for heart failure, including intravenous (IV) or higher-dose diuretic therapy.
  * Elevated heart failure biomarker levels (BNP or NT-proBNP) within the past 6 months.

Note: Participants with NYHA Class II symptoms must have both a recent heart failure worsening event and elevated biomarker levels. Participants with NYHA Class III or IVa symptoms must have either a recent heart failure worsening event or elevated biomarker levels.

* Stable Optimized GDMT - Maintained 6 months post-implant (includes stable GLP-1 RA)

Refined HFrEF Subgroup Exclusion Criteria:

* Severe HF defined as one or more of the following:

  * Ambulatory NT-proBNP value \>5,000 pg/ml or BNP value \>1,600 pg/ml
  * Left ventricular end-diastolic diameter (LVEDD) \>8 cm
  * Left ventricular ejection fraction (LVEF) \< 20%
  * ACC/AHA Stage D HF or non-ambulatory NYHA Class IV HF
  * Inotropic infusion (continuous or intermittent) within the past 6 months
  * Active listing on the cardiac transplant waiting list
* More than mild right ventricular dysfunction
* Valve disease

  * Mitral regurgitation \> moderate
  * Mitral stenosis \> mild
  * Tricuspid regurgitation \> moderate
  * Aortic regurgitation \> moderate
  * Aortic stenosis \> moderate
* Body mass index (BMI) ≥45
* Myocardial infarction and/or any therapeutic invasive, non-valvular cardiac procedure within the past 3 months, or current indication for coronary revascularization
* Stroke, transient ischemic attack, deep vein thrombosis, or pulmonary embolus within the past 6 months
* Cardiac resynchronization therapy implanted within the past 12 months
* Renal insufficiency as determined by serum creatinine (sCr) level \>2.5 mg/dL or estimated glomerular filtration rate (eGFR) \<25 ml/min/1.73 m2
* Performance of the 6-minute walk test with a distance \<100 m or \>450 m
* Active endocarditis or infection requiring intravenous antibiotics within 3 months of scheduled index procedure
* Presence of one or more of the following resting hemodynamic findings:

  1. Mean pulmonary capillary wedge pressure (PCWP) \>35 mmHg
  2. Mean right atrial pressure (RAP) \>15 mmHg
  3. Mean PCWP-mean RAP gradient \< 5 mmHg
  4. Pulmonary vascular resistance (PVR) ≥5 Wood Units (WU)
  5. Cardiac index \<1.8 L/min/m2