HaemoDialysis Interventions to REduce Multi-Organ Dysfunction and Effect on Quality of Life Assessed by MRI Scanning

Exclusion Criteria: * Change in dry weight (clinically defined) in 4 weeks prior to recruitment * Dialysate composition other than: sodium≥137mmol/L, potassium≥2.0mmol/L, calcium≥1.5mmol/L, magnesium≥0.5mmol/L, glucose 1.0g/L * Instability on dialysis in 4 weeks prior to recruitment leading to either: * Emergency medical attention * Infusion of additional fluid * Loss in consciousness * Arrhythmia * Chest pain * Or any other medical condition that precludes the scan session in opinion of the investigator * Dialysed via a synthetic line, central venous catheter or graft * Qa \< 500ml/min * NYHA Stage IV heart failure (New York Heart Association) * Active infection or malignancy * Contraindication to MRI scanning including claustrophobia, pacemaker, metallic implants etc * Pregnancy (pregnancy test will be conducted with female patients aged ≤ 55 years) or planning pregnancy or lactation period * Medical conditions or overall physical frailty precludes scan session in opinion of investigator * Unable or unwilling to provide informed consent * Any condition which could interfere with the patient's ability to comply with the study * Participation in an interventional clinical study during the preceding 30 days Inclusion Criteria: * Age 18-80, male and female * Informed consent signed and dated by study patient and investigator/authorised physician * Average (4 weeks prior to recruitment) Ultrafiltration volumes ≥ 0.5 litres/ dialysis session * Receiving dialysis via an arteriovenous fistula * Must be able to follow simple instruction in English (on safety grounds for MRI scans) and be able to understand the nature and requirements of the study * Stable dialysis prescription * CKD5 (Chronic kidney disease) patients having renal replacement therapy with haemodialysis/ haemodiafiltration (\>90 days)