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Minimally invasive versus conventional sternotomy for Mitral valve repair: protocol for a multicentre randomised controlled trial (UK Mini Mitral)
  1. Rebecca H Maier1,
  2. Adetayo S Kasim2,
  3. Joseph Zacharias3,
  4. Luke Vale4,
  5. Richard Graham5,
  6. Antony Walker3,
  7. Grzegorz Laskawski3,
  8. Ranjit Deshpande6,
  9. Andrew Goodwin5,
  10. Simon Kendall5,
  11. Gavin J Murphy7,
  12. Vipin Zamvar8,
  13. Renzo Pessotto8,
  14. Clinton Lloyd9,
  15. Malcolm Dalrymple-Hay9,
  16. Roberto Casula10,
  17. Hunaid A Vohra11,
  18. Franco Ciulli11,
  19. Massimo Caputo12,
  20. Serban Stoica11,
  21. Max Baghai6,
  22. Gunaratnam Niranjan13,
  23. Prakash P Punjabi10,
  24. Olaf Wendler6,
  25. Leanne Marsay1,
  26. Cristina Fernandez-Garcia4,
  27. Paul Modi14,
  28. Bilal H Kirmani14,
  29. Mark D Pullan14,
  30. Andrew D Muir14,
  31. Dimitrios Pousios14,
  32. Helen C Hancock1,
  33. Enoch Akowuah5
  1. 1Newcastle Clinical Trials Unit, Newcastle University, Newcastle upon Tyne, UK
  2. 2Department of Anthropology, Durham University, Durham, UK
  3. 3The Lancashire Cardiac Centre, Blackpool Teaching Hospitals NHS Foundation Trust, Blackpool, UK
  4. 4Health Economics Group, Population Health Sciences Institute, Newcastle University, Newcastle, UK
  5. 5Cardiothoracic Surgery, South Tees Hospitals NHS Foundation Trust, Middlesbrough, UK
  6. 6Cardiothoracic Surgery, King's College Hospital NHS Foundation Trust, London, UK
  7. 7Department of Cardiovascular Sciences and NIHR Leicester Biomedical Research Unit in Cardiovascular Medicine, University of Leicester, Leicester, UK
  8. 8Cardiothoracic Surgery, Royal Infirmary of Edinburgh, Edinburgh, UK
  9. 9Cardiothoracic Surgery, University Hospitals Plymouth NHS Trust, Plymouth, UK
  10. 10Cardiothoracic Surgery, Imperial College Healthcare NHS Trust, London, UK
  11. 11Cardiothoracic Surgery, University Hospitals Bristol NHS Foundation Trust, Bristol, UK
  12. 12Bristol Heart Institute, University of Bristol, Bristol, UK
  13. 13Cardiac Surgery, Liverpool Heart and Chest Hospital NHS Foundation Trust, Liverpool, UK
  14. 14Cardiothoracic Surgery, Liverpool Heart and Chest Hospital NHS Foundation Trust, Liverpool, UK
  1. Correspondence to Rebecca H Maier; Rebecca.Maier{at}


Introduction Numbers of patients undergoing mitral valve repair (MVr) surgery for severe mitral regurgitation have grown and will continue to rise. MVr is routinely performed via median sternotomy; however, there is a move towards less invasive surgical approaches.

There is debate within the clinical and National Health Service (NHS) commissioning community about widespread adoption of minimally invasive MVr surgery in the absence of robust research evidence; implementation requires investment in staff and infrastructure.

The UK Mini Mitral trial will provide definitive evidence comparing patient, NHS and clinical outcomes in adult patients undergoing MVr surgery. It will establish the best surgical approach for MVr, setting a standard against which emerging percutaneous techniques can be measured. Findings will inform optimisation of cost-effective practice.

Methods and analysis UK Mini Mitral is a multicentre, expertise based randomised controlled trial of minimally invasive thoracoscopically guided right minithoracotomy versus conventional sternotomy for MVr. The trial is taking place in NHS cardiothoracic centres in the UK with established minimally invasive mitral valve surgery programmes. In each centre, consenting and eligible patients are randomised to receive surgery performed by consultant surgeons who meet protocol-defined surgical expertise criteria. Patients are followed for 1 year, and consent to longer term follow-up.

Primary outcome is physical functioning 12 weeks following surgery, measured by change in Short Form Health Survey (SF-36v2) physical functioning scale. Early and 1 year echo data will be reported by a core laboratory. Estimates of key clinical and health economic outcomes will be reported up to 5 years.

The primary economic outcome is cost effectiveness, measured as incremental cost per quality-adjusted life year gained over 52 weeks following index surgery.

Ethics and dissemination A favourable opinion was given by Wales REC 6 (16/WA/0156). Trial findings will be disseminated to patients, clinicians, commissioning groups and through peer reviewed publication.

Trial registration number ISRCTN13930454.

  • cardiac surgery
  • cardiothoracic surgery
  • health economics

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  • HCH and EA are joint senior authors.

  • Twitter @VipinZamvar

  • Contributors EA and JZ conceived the idea for the trial. EA, RHM, HCH, ASK, GJM, JZ and LV codesigned the trial, secured funding from NIHR HTA and wrote the protocol. EA is chief Investigator. RHM and HCH provide methodological input and oversee NCTU activity. ASK leads statistical aspects and analysis. LV leads health economic aspects and analysis, supported by CF-G. LM manages the trial. RG leads the core laboratory. GJM provides ongoing clinical and academic contributions. JZ, AW, GL, RD, AG, SK, VZ, RP, CL, MD-H, RC, HAV, FC, SS, MC, MB, GN, PPP, OW, PM, BHK, MDP, ADM and DP are surgeons in the trial and who have contributed to ongoing trial design and the Statistical Analysis Plan. This paper was drafted from the approved version of the protocol, version 5.0, 18th June 2020; all authors commented and amended drafts of the paper and approved the final manuscript.

  • Funding This work is supported by a National Institute for Health Research (NIHR) Health Technology Assessment (HTA) Programme (Ref: 14/192/110). The UK Mini Mitral Trial is sponsored by South Tees Hospitals NHS Foundation Trust.

  • Competing interests LV was a member of the NIHR Health Technology Assessment Clinical Evaluation and Trials Panel from 2015 to 2018.

  • Patient and public involvement Patients and/or the public were involved in the design, or conduct, or reporting, or dissemination plans of this research. Refer to the Methods section for further details.

  • Provenance and peer review Not commissioned; peer reviewed for ethical and funding approval prior to submission.