Remote Ischemic Preconditioning Reduces Perioperative Cardiac and Renal Events in Patients Undergoing Elective Coronary Intervention: A Meta-Analysis of 11 Randomized Trials

Background: Results from randomized controlled trials (RCT) concerning cardiac and renal effect of remote ischemic preconditioning(RIPC) in patients with stable coronary artery disease(CAD) are inconsistent. The aim of this study was to explore whether RIPC reduce cardiac and renal events after elective percutaneous coronary intervention (PCI). Methods and Results: RCTs with data on cardiac or renal effect of RIPC in PCI were searched from Pubmed, EMBase, and Cochrane library (up to July 2014). Meta-regression and subgroup analysis were performed to identify the potential sources of significant heterogeneity(I-2 >= 40%). Eleven RCTs enrolling a total of 1713 study subjects with stable CAD were selected. Compared with controls, RIPC significantly reduced perioperative incidence of myocardial infarction (MI) [odds ratio(OR) =0.68; 95% CI, 0.51 to 0.91; P=0.01; I(2=)41.0%] and contrast-induced acute kidney injury(AKI) (OR=0.61; 95% CI, 0.38 to 0.98; P=0.04; I-2=39.0%). Meta-regression and subgroup analyses confirmed that the major source of heterogeneity for the incidence of MI was male proportion (coefficient =-0.049; P=0.047; adjusted R-2=0.988; P=0.02 for subgroup difference). Conclusions: The present meta-analysis of RCTs suggests that RIPC may offer cardiorenal protection by reducing the incidence of MI and AKI in patients undergoing elective PCI. Moreover, this effect on MI is more pronounced in male subjects. Future high-quality, large-scale clinical trials should focus on the long-term clinical effect of RIPC.