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Remote ischaemic preconditioning for heart surgery. The study design for a multi-center randomized double-blinded controlled clinical trial--the RIPHeart-Study.

AIMS
Transient ischaemia of non-vital tissue has been shown to enhance the tolerance of remote organs to cope with a subsequent prolonged ischaemic event in a number of clinical conditions, a phenomenon known as remote ischaemic preconditioning (RIPC). However, there remains uncertainty about the efficacy of RIPC in patients undergoing cardiac surgery. The purpose of this report is to describe the design and methods used in the "Remote Ischaemic Preconditioning for Heart Surgery (RIPHeart)-Study".


METHODS
We are conducting a prospective, randomized, double-blind, multicentre, controlled trial including 2070 adult cardiac surgical patients. All types of surgery in which cardiopulmonary bypass is used will be included. Patients will be randomized either to the RIPC group receiving four 5 min cycles of transient upper limb ischaemia/reperfusion or to the control group receiving four cycles of blood pressure cuff inflation/deflation at a dummy arm. The primary endpoint is a composite outcome (all-cause mortality, non-fatal myocardial infarction, any new stroke, and/or acute renal failure) until hospital discharge.


CONCLUSION
The RIPHeart-Study is a multicentre trial to determine whether RIPC may improve clinical outcome in cardiac surgical patients.