Post Approval Study (PAS) of the OPTIMIZER Smart and CCM Therapy

Inclusion Criteria: 1. Patient provides written authorization and/or consent per institution and geographical requirements 2. Male or non-pregnant female, aged 18 or older 3. Left ventricular ejection fraction of 25-45% (inclusive, per site assessment) 4. NYHA Class III heart failure symptoms 5. Stated willingness to comply with all study procedures and availability for the duration of the study 6. Patient has been treated with guideline-directed medical therapy Exclusion Criteria: 1. Primary heart failure due to uncorrected mitral valve disease, or mitral valve repair or clip within 90 days of implant 2. IV inotropes, hemofiltration, or any form of positive inotropic support within 30 days prior to implant 3. Myocardial infarction within 90 days prior to implant 4. Undergone a CABG procedure within 90 days or a PTCA procedure within 30 days of implant 5. Prior heart transplant or ventricular assist device 6. Mechanical tricuspid valve 7. Receiving cardiac resynchronization therapy (CRT) or has a Class I indication for CRT implantation according to the ACCF/AHA/HRS guidelines for device-based therapy 8. Participating in a cardiac investigational study at the same time 9. Patient is in a vulnerable population (such as significant mental disability, prisoner) that in the judgement of the PI impedes ability to provide informed consent.