Newly formed dialysis fistulae can often fail, and failure is usually due to narrowing of the blood vessels. Methods of detecting narrowing are available and, more importantly, can detect narrowings before a fistula fails. It is not known whether treating these narrowings will actually improve fistula survival or if the majority can be left alone. we wish to see if we can detect such narrowings with ultrasound scanning and if early detection and treatment improves patient outcomes.

Inclusion Criteria:

1. Incident patients referred to vascular or transplant surgery departments for primary AV fistula formation for haemodialysis access.
2. Ability to give informed written consent
3. Aged over 18 at time of referral

Exclusion Criteria:

1. Inability to give informed written consent
2. Aged under 18 at time of referral
3. Inability to attend follow-up appointments

Specific exclusion;

1. Previous arteriovenous access procedures in target limb
2. Unsuitable for upper limb radiocephalic or brachiocephalic AVF formation
3. Known thrombophilic or thrombotic pathology