Conventional versus Minimally Invasive extra-corporeal circulation in patients undergoing Cardiac Surgery: a randomised controlled trial.
A non-CTIMP multicentre randomised controlled trial comparing conventional heart-lung machines with miniaturised heart-lung machines in cardiac surgery. The trial is coordinated by Clinical Trials and Evaluation Unit Bristol at the University of Bristol. The University of Bristol is acting as Sponsor in the UK, and ‘Lead Coordinating Centre’ for overseas centres. Overseas recruitment was included as only a small number of UK centres could deliver the intervention, and collaborators in Greece are leaders in the use of the miniaturised heart-lung machines and were instrumental in initiating this trial. Where possible we are using a lead site in each country. We have used the Minimal Invasive Extracorporeal Technologies International Society (MiECTiS) to increase awareness of the trial and engage with potential sites. At least 25 participating sites are planned across the UK, Europe and the rest of the world.


Countries: Greece, Switzerland, Germany, UK, Italy, Saudi Arabia, Turkey, Israel, Canada, Netherlands.
Sites may also be opened in USA, Australia, and New Zealand.


UK sites Sponsored by the University of Bristol. The University of Bristol acts a ‘Lead Coordinating Centre’ for the overseas sites but has avoided the term ‘Sponsor’


The University of Bristol has funding to cover the coordinating centre costs, but there is currently no funding for site costs for UK or overseas sites.


The Statement of Activities is used as the agreement with UK sites. The University of Bristol holds agreements with each overseas site to cover the expectations on both sides and that applicable Laws.


The University of Bristol and the NHS provide insurance for the UK; overseas sites must provide their own indemnity.

Research Governance

This is coordinated by CTEU Bristol for the UK sites, but the overseas sites are responsible for this own research approvals.


Single protocol. Pragmatic trial design, operative specifics and operative decision making are at the discretion of the operating surgeon. Components of the heart-lung machine are specified, rather than the make/model.


Central monitoring is performed by CTEU Bristol.

Distribution of Trial Supplies


Data Collection

Via an online database hosted on the NHS network for UK sites and the University of Bristol network for overseas sites. Paper CRFs are also provided.

Sample Collection


Health Economics/PROMS

Local sites will collect resource use. EQ5DL is used as a quality of life measure. This is sent out by CTEU Bristol, for UK sites and managed locally by overseas sites.

Data Ownership & Publication

Investigators retain the right to their own site’s data. The main results paper will be written by a writing committee with representation from sites.


Obstacles encountered
Funding has been hard to secure; an application was made to the British Heart Foundation for the UK part of the trial, and the European collaborators applied for a European grant. Neither funding body would confirm funding without the confirmation that the other funder was committed, and so neither grant was awarded. The Sponsor is only a Sponsor for the UK sites, and prefers to be known as the ‘Lead Coordinating Centre’ for overseas centres, although as yet this has not been an issue for sites. The Sponsor’s insurance does not cover overseas sites, and we have to trust that sites have in place or secure the appropriate insurance cover. Our trial databases are hosted within the NHS N3 network which would not be accessible to non-UK sites; our IT team have built a ‘mirror’ database on our University of Bristol server that can be accessed by non-UK sites. One site (Switzerland) have requested changes to the protocol to meet local standards, this discussion is currently ongoing. Due to the collaborative nature of the study, the standard data sharing clauses of the site agreements required revision.