MP221
EFFECTS OF ISCHAEMIC CONDITIONING ON MAJOR CLINICAL OUTCOMES IN PEOPLE UNDERGOING INVASIVE PROCEDURES: A SYSTEMATIC REVIEW AND METAANALYSIS Free

Introduction and Aims: The purpose of ischaemic conditioning is mitigation of the effects of ischaemia-reperfusion injury. We performed a systematic review to assess its therapeutic value.

Methods: We systematically searched Medline, EMBASE and the Cochrane Database (1950 to October 2015) for randomised controlled trials assessing the effects of ischaemic conditioning compared with no ischaemic conditioning on major clinical outcomes. Summary estimates of risk ratios (RR) for all-cause mortality and other pre-specified clinical outcomes were calculated using random effects models. The impact of pre-specified characteristics was tested using meta-regression and the Cochran C test. Small study bias for the primary outcome was assessed by the Harbord and Peters methods.

Results: In 92 identified trials ischaemic conditioning had no impact on all-cause mortality (45 trials, 11,061 participants, RR 0·95, 95% confidence interval [95%CI] 0.78-1.15, p=0·57). The only characteristics affecting the impact on mortality were related to trial design (sample size and follow-up period) and none to the delivery of the intervention itself. Ischaemic conditioning reduced rates of myocardial infarctions (32 trials, 8,153 participants, RR 0·80, 95%CI 0·65-1·00, P=0·05), strokes (18 trials, 5,768 participants, RR 0·65, 95%CI 0·43-0·99, P=0·04), and any reported acute kidney injury (AKI) (33 trials, 8,227 participants (RR 0·82, 95%CI 0·70-0·96, P=0·01) but had no impact on the cardiovascular event composite, new onset arrhythmia, the Acute Kidney Injury Network (AKIN)-defined AKI or transplant graft function.Trials were generally deemed at low or unclear risk of bias with no statistical evidence of small study bias.

Conclusions: There is no evidence ischaemic conditioning reduces all-cause mortality. It may reduce myocardial infarction, stroke and acute kidney injury although results for the cardiovascular event composite and more tightly defined grades of acute kidney injury are incongruous.Evidence of benefit generated by high quality trials is needed before adoption into routine clinical practice can be recommended.