Inclusion Criteria:

• 1. End-stage heart failure due to ischemic or non-ischemic cardiomyopathy
• a. If implanted for destination therapy indication, must have New Your Heart Association (NYHA) Class IV Heart Failure AND left ventricular ejection fraction (LVEF) \<25% OR maximum minute consumption of oxygen (VO2) \<14 OR on requirement for continuous intravenous inotropes
• 2. Meet clinical and socioeconomic screening criteria for elective LVAD implantation by the University of Washington Mechanical Circulatory Support Program
• 3. Scheduled (or soon to be scheduled) for elective LVAD implantation
• 4. Age \>18 years

Exclusion Criteria:

• 1. End-stage heart failure due to causes other than ischemic or non-ischemic cardiomyopathy (e.g., valvular, hypertrophic or infiltrative cardiomyopathies).
• 2. Disease that disqualifies from consideration for LVAD implantation by the University of Washington program:
• 1. Cirrhosis as evidenced by liver biopsy
• 2. Irreversible, severe renal disease (estimated glomerular filtration rate (eGFR) \<30) or on chronic dialysis
• 3. Untreated thyroid disease (hyper- or hypo-thyroidism)
• 4. Severe complications of diabetes, such as diabetes-related amputation, severe retinopathy, peripheral neuropathy or diabetic renal disease (eGFR \<30)
• 3. Tissue physiology or other factors that, in the opinion of the Cardiac Surgeons, make the patient at unacceptably high risk for adverse outcomes.
• 4. Non-compliance with current treatments, including failure to follow prescribed therapies, such as medications, clinic visits, diagnostic testing and behavioral contracts
• 5. Active use/abuse of illicit substances
• 6. Lack of adequate caregiver support to help patient manage LVAD
• 7. Known allergies to niacin, nicotinamide or warfarin
• 8. Inability to perform Study visits or procedures
• 9. Unwillingness/inability to provide informed consent.
• 10. Participants considered by the attending cardiologist and/or the investigator to be unsuitable for the study