Meta-analysis of remote ischemic conditioning in patients with acute myocardial infarction

Effects of remote ischemic conditioning (RIC) in acute myocardial infarction (AMI) patients remain conflicting. We performed this meta-analysis of randomized clinical trials (RCTs) to evaluate the benefits of the RIC in patients with AMI. Potentially relevant RCTs were identified by searching PubMed, Embase, Cochrane Library, VIP, CNKI, and Wanfang database until November 2016. RCTs evaluating RIC using intermittent limb ischemia-reperfusion in AMI patients were included. Thirteen RCTs were identified and analyzed. Meta-analysis showed that RIC significantly reduced the area under the curve (AUC) of creatine kinase-myocardial band (CK-MB) (standardized mean difference [SMD] -0.29; 95% confidence intervals [CI] -0.44 to -0.14; P = 0.0002) and AUC of troponin T (SMD -0.22; 95% CI -0.37 to -0.08; P = 0.003). Risk ratio (RR) for ≥70% ST-segment resolution favored RIC group than the control group (RR 1.39; 95% CI 1.03-1.86; P = 0.03). RIC also significantly reduced all-cause mortality (RR 0.33; 95%CI 0.17-0.64; P = 0.001). Subgroup analyses on the CK-MB AUC and ST-segment resolution ≥70% rate showed that the effects of RIC appeared to be affected by the limb used, duration of RIC, and clinical setting. RIC may offer cardioprotective effects by improving ST-segment resolution and reducing the infarct size in AMI patients.