IRONHEART: Intravenous Iron in Non-ischaemic Heart Failure

The aim of this study is to observe the effect of intravenous ferric derisomaltose in participants with non-ischaemic heart failure (LVEF\<40%), iron deficiency (TSATS\<20%) and established on heart failure therapy including Sodium-glucose cotransporter 2 inhibitors (SGLT2i). Participants will undergo baseline laboratory blood tests, cardiac magnetic resonance imaging (cMRI), six-minute walk test, musculoskeletal function test and Kansas City Cardiomyopathy Questionnaire (KCCQ). These investigations will be repeated at 24 hours and 30 days after the administration of intravenous ferric derisomaltose.