Tiny heart implant aims to unclog lungs and save lives in advanced heart failure

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: 1. Heart failure with a reduced LV ejection fraction (≤40%) and documented heart failure for at least 6 months from Baseline Visit. 2. NYHA Class III symptoms 3. Receiving guideline directed medical therapy (GDMT) for heart failure which refers to those HF drugs carrying a Class I indication: 1. An inhibitor of the renin-angiotensin system (RAS inhibitor), including an angiotensin receptor-neprilysin inhibitor (ARNI), angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) and an evidence-based beta-blocker (BB) for at least 3 months prior to the Baseline Visit 2. An SGLT2I Inhibitor for at least 1 month prior to the Baseline Visit 3. Other medications recommended for selected populations, e.g., on diuretics as required for volume control. Mineralocorticoid receptor antagonist (MRA) or nitrates/hydralazine should be used in appropriate patients, according to the published guidelines. 4. All patients are on stable HF medications as determined by the investigator, for at least 1 month, with the exception of diuretic therapy. Stable is defined as no more than a 100% increase or 50% decrease in dose within these periods. 4. Receiving Class I recommended cardiac rhythm management device therapy. Specifically: if indicated by class I guidelines, cardiac resynchronization therapy (CRT), implanted cardioverter-defibrillator (ICD) or a pacemaker should be implanted at least 3 months prior to Baseline Visit. 5. Must meet 5a OR 5b. 1. One (1) prior Heart Failure Hospitalization with duration \>24 hours or Emergency Room Heart Failure Visit with duration ≥6 hours, or Heart Failure Clinic ADHF Visit with duration ≥6 hours, within 12 months from Baseline Visit. 2. Alternatively, if patients have not had a HF hospitalization or ER HF Visit within the prior 12 months, they must have a BMI corrected elevated Brain Natriuretic Peptide (BNP) level of at least 300 pg/ml or an N-terminal pro-BNP (NT-proBNP) level of at least 1,500 pg/ml, according to local measurement, within 3 months of the Baseline Visit. 6. Able to perform the 6-minute walk test with a distance ≥100 meters and ≤450 meters. 7. Provide written informed consent for study participation and be willing and able to comply with the required tests, treatment instructions and follow-up visits. Main Exclusion Criteria: * Resting systolic blood pressure \<90 or \>160 mmHg * Baseline echocardiographic evidence of intracardiac blood clot, significant right ventricular dysfunction or severe left sided dilation. * Diagnosis of severe pulmonary hypertension. * Congenital Atrial septal defect, patent foramen ovale, with known shunting on echo * Untreated moderately severe or severe aortic or mitral stenosis. * Mitral valve repair device (e.g. MitraClip) implanted within 3 months prior to Baseline Visit. * Acute MI, acute coronary syndrome (ACS), percutaneous coronary intervention (PCI), rhythm management system revision (not including generator change), lead extraction, or cardiac or other major surgery within 3 months of Baseline Visit. * Stroke, transient ischemic attack (TIA), systemic or pulmonary thromboembolism, or deep vein thrombosis (DVT) within 6 months. * Intractable HF with any of the following: Treatment with IV vasoactive medications (e.g., IV inotropes, IV vasodilators) within the last 30 days. Treated with a ventricular assist device (VAD). Listed for cardiac transplantation. * Prior cardiac transplantation. * Life expectancy \<1 year due to non-cardiovascular illness. * Kidney failure or is receiving dialysis. * Active infection requiring parenteral or oral antibiotics. * Known allergy to nickel. * Hemodynamic, heart rhythm or respiratory instability at the time of Final Exclusion Criteria.