Remote ischaemic conditioning in percutaneous coronary intervention: a meta-analysis of randomised trials

Abstract

Introduction: It remains uncertain whether remote ischaemic conditioning (RIC) using cycles of limb ischaemia-reperfusion as a conditioning stimulus benefits patients undergoing percutaneous coronary intervention (PCI).

Aim: We performed a meta-analysis toassessthe effect of RIC in PCI.

Material and methods: The PubMed, EMBASE, Web of Science, and CENTRAL databases were searched for randomised controlled trials (RCTs) comparing RIC with controls. The treatment effects were measured as a pooled odds ratio (OR), standardised mean difference (SMD), and corresponding 95% confidence intervals (95% CIs) using random-effects models.

Results: Fourteen RCTs, including 2,301 patients, were analysed. Compared to the controls, RIC significantly reduced the cardiac enzyme levels (SMD = -0.21; 95% CI: -0.39 to -0.04; p = 0.015; heterogeneity test, I (2) = 75%), and incidence of PCI-related myocardial infarction (OR = 0.70; 95% CI, 0.51-0.98; p = 0.037). There was a trend toward an improvement in the complete ST-segment resolution rate with RIC (OR = 1.83; 95% CI: 0.99-3.40; p = 0.054). No significant difference could be detected between the two groups regarding the risk for acute kidney injury after PCI. Univariate meta-regression analysis suggested that the major source of significant heterogeneity was the PCI type (primary or non-emergent) for the myocardial enzyme levels (adjusted R (2) = 0.44). Subsequent subgroup analysis confirmed the results.

Conclusions: The present meta-analysis showed that RIC could confer cardioprotection for patients undergoing coronary stent implantation. Moreover, the decrease in the myocardial enzyme levels was more pronounced in the patients treated with primary PCI.

Keywords: meta-analysis; percutaneous coronary intervention; remote ischaemic postconditioning; remote ischaemic preconditioning.

Figure 1

Flow diagram of the review process, according to the PRISMA statement PRISMA – Preferred Reporting Items for Systematic reviews and Meta-Analyses, PCI – percutaneous coronary intervention, RCT – randomised controlled trial

Figure 2

Forest plot for myocardial enzyme levels, expressed as standardised mean differences (SMDs) with 95% CIs RIC – remote ischaemic conditioning, CI – confidence interval, df – degree of freedom

Figure 3

Forest plot for PCI-related myocardial infarction with or without remote ischaemic conditioning (RIC) in patients undergoing non-emergent PCI OR – odds ratio, CI – confidence interval, df – degree of freedom

Figure 4

Forest plot for complete ST-segment resolution with or without remote ischaemic conditioning (RIC) in patients undergoing primary PCI OR – odds ratio, CI – confidence interval, df – degree of freedom