Arteriovenous fistula ligation after transplantation - COBALT v1.0

  • Research type

    Research Study

  • Full title

    Should we ligate haemodialysis fistulas in patients after they have been transplanted successfully: the COBALT feasibility study (Cardiorespiratory Optimisation By AVF Ligation after Transplantation).

  • IRAS ID

    305610

  • Contact name

    Gavin Pettigrew

  • Contact email

    gjp25@cam.ac.uk

  • Sponsor organisation

    Cambridge University Hospitals NHS Foundation Trust and University of Cambridge

  • ISRCTN Number

    ISRCTN49033491

  • Duration of Study in the UK

    1 years, 8 months, 1 days

  • Research summary

    Kidney transplantation is the best form of treatment for most patients with kidney failure. Although outcomes from transplantation are very good, people with a working transplant do not live as long as the general population, with a fifth of transplant patients dying from heart disease.

    Before they receive a transplant, patients often require a period of haemodialysis, whereby the blood is cleansed by regularly attaching the patient to an artificial kidney machine. For this, patients often have an operation to create an arteriovenous fistula, which involves joining a vein in the arm directly onto a nearby artery. Once created, the fistula vein expands and the blood flow through the vein increases markedly. While this is ideal for providing access for haemodialysis, the increased blood flow means that the heart must work harder, and studies have shown that the heart becomes bigger and its muscle thicker. Although not proven, it seems likely that these changes to the heart may contribute to the extra deaths from heart disease.

    Our study will examine whether an operation to disconnect the fistula vein from the artery improves heart function in kidney transplant patients. As preliminary work for a much larger study, we will recruit forty consenting patients with good, stable kidney transplant function, and who still have a working fistula. All patients will have a special test that measures the very limit to which they can exercise; this shows how well their heart is functioning.
    The patients will be randomly assigned to either have their fistula left alone or to have it disconnected, and the exercise test will be repeated six months later. Patients will also wear a wrist monitor that records their activity levels before and after fistula disconnection, and we will assess if patients feel their quality of life has changed following the operation.

  • REC name

    East Midlands - Derby Research Ethics Committee

  • REC reference

    22/EM/0002

  • Date of REC Opinion

    2 Feb 2022

  • REC opinion

    Further Information Favourable Opinion