Background: Ischaemia-reperfusion injury occurs during heart surgery that uses cardiopulmonary bypass (CPB) and
cardioplegic arrest. It is hypothesised that remote ischaemic preconditioning (RIPC) protects the heart against such
injury. Despite the numerous studies investigating the protective effects of RIPC, there is still uncertainty about the
interpretation of the findings as well as conflicting results between studies. The objective of this trial is to
investigate the cardioprotective effect of RIPC in patients having coronary artery bypass grafting (CABG) or aortic
valve replacement surgery. This will be achieved by estimating the effect of the intervention in the two groups of
pathologies and by investigating the signalling mechanisms that may underpin the cardioprotective effect.
Methods/Design: A two-centre randomised controlled trial will be used to investigate the effects of RIPC in two
pathologies: patients having isolated CABG and those having aortic valve replacement surgery (AVR) with CPB.
Participants will be randomised to RIPC or control (sham RIPC), stratified by surgical stratum. The intervention
will be delivered by a research nurse. Data will be collected by a research nurse blinded to the intervention.
The patient and the theatre staff are also blinded to the allocation. Markers of myocardial injury and inflammation
will be measured in myocardial biopsies and in blood samples at different times.
Discussion: This trial is designed to investigate whether RIPC will reduce myocardial injury and inflammation
following heart surgery and whether there is a difference in effect between participants having CABG or AVR.
This trial is a unique opportunity to study the mechanisms associated with RIPC using human myocardial tissue
and blood, and to relate these to the extent of myocardial injury/protection.
Trial registration: Current Controlled Trials ISRCTN33084113 (25 March 2013).