- To evaluate the effects of IV iron supplementation on exercise duration, left ventricular (LV) structure and function, symptom status (NYHA class, Minnesota Living with Heart Failure Questionnaire [MLHFQ], and subjective fatigue score), and haematological and biochemical (haemoglobin [Hb], haematocrit [Hct], iron status, N-BNP, cytokines and oxidative stress) indices.