Dynamic Effects of Online HDF on Cardiac Function and Myocardial Perfusion Utilising Cardiac MRI (CAMRID)

Trial Configuration: Non-blinded crossover pilot study Setting: Secondary care Sample size estimate: This is a pilot study therefore power calculations are not appropriate. A group size of 12 participants has been selected for feasibility.

Number of participants: 12 patients to complete study Description of interventions

• 6 sessions of conventional haemodialysis each lasting 4 hours
• 6 sessions of online haemodiafiltration each lasting 4 hours
• 2 sessions of Cardiac MRI each lasting 6 hours in total to take place around 6th session of dialysis Randomisation and blinding: This is an open study. Statistical methods: All continuous variables will be tested for normality. The primary and continuous secondary endpoints will be compared between the two modalities using a paired t test or Wilcoxon signed rank test as appropriate. The association between categorical variables will be tested using the Chi squared or Fischer's Exact test. An alpha error at 0.05 will be judged as significant.

Inclusion criteria

• Age 18-75 years
• Able to give informed consent
• CKD5 on chronic haemodialysis
• Receiving dialysis via an arteriovenous fistula
• Must be able to follow simple instruction in English (on safety grounds for MRI scans)

Exclusion criteria

• Change in ideal dry weight in 4 weeks prior to recruitment
• 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
• Dialysed via a synthetic line or graft
• Qa < 500ml/min
• NYHA Stage IV heart failure
• Active infection or malignancy
• Contraindication to MRI scanning including claustrophobia
• Mental incapacity to consent
• Pregnancy or planning pregnancy