IRONHEART: Intravenous Iron in Non-ischaemic Heart Failure

Inclusion Criteria: * Participants capable of giving informed consent. * Aged 18yrs and above. * Diagnosed with heart failure and a reduction of their ejection fraction \< 40% by any modality. * Non ischaemic cardiomyopathy as determined by baseline cardiac magnetic resonance imaging. * Iron deficient per this definition: Transferrin saturations \< 20%. * Established on Heart failure therapy including SGLT2i therapy for a minimum of four weeks prior to recruitment. * New York Heart Association score of I - III class. Exclusion Criteria: * New York Heart Association classification Score \>IV * Ischaemic cardiomyopathy * Chronic kidney stage: Estimated Glomerular Filtration Rate (eGFR) \< 30 * Requirement for renal dialysis * Atrial fibrillation / atrial flutter * Non cardiac and cardiac palliative diagnosis * Active cancer diagnosis * Moderate to severe valvular heart disease * Cardiac electronic implantable device: Cardiac resynchronization therapy, Implantable cardioverter-defibrillator, left ventricular assist device * Cardiac \& non cardiac transplant participants * Myocardial infarction, Percutaneous Coronary Intervention, Coronary Artery Bypass Graft surgery in the last 30 days * Complex congenital heart disease * Pregnancy