Adjunct remote ischemic conditioning to PCI in ST-segment elevation myocardial infraction patients: Systematic review and meta-analysis

Abstract Introduction ST-segment elevation myocardial infarction (STEMI) is the most dangerous presentation of the acute coronary syndrome (ACS). Throughout the last three decades, clinicians have been attempting to reduce the short and long-term major adverse cardiac events (MACE) associated with STEMI. Remote ischemic conditioning (RIC) is one of the new adjunctive modalities to PCI in treating STEMI patients whereby brief reversible episodes of ischemia and reperfusion are applied to the tissue (by alternative cycles of inflation and deflation of a blood pressure cuff on the upper or lower limb) confers global protection and renders remote tissues resistant to ischemia/reperfusion injury. This review aims to provide reliable evidence from published randomized controlled trials (RCTs) regarding whether RIC is beneficial for STEMI patients or not. Methods We followed the PRISMA guidelines during the preparation of this systematic review and meta-analysis. A computer literature search for (PubMed, Web of Science, Scopes, and Google Scholar) was carried out. We included RCT, comparing the remote ischemic conditioning, regardless of its timing of application to PCI, with either placebo or sham procedure, in terms of both short-term and long-term cardio protection. Outcomes of myocardial salvage index, myocardial infarction size, and left ventricular ejection fraction were pooled as the standardized mean difference between the two groups from baseline to endpoint. Results 11 RCTs (7151 patients), were included in this analysis. The overall effect on short-term outcomes, was in favor of PCI only in terms of myocardial salvage index(P value=0.04, 95% CI [0.00-0.08]), and left ventricular ejection fraction(P value=0.05, 95% CI [0.02,2.16]), while the adjunctive application of remote ischemic conditioning was beneficial in terms of: myocardial infarct size ( P value=0.004, 95% CI [-3.22,-0.62]). Regarding the long-term outcomes, the overall effect did not show any benefit in either of the two groups in terms of: major adverse cardiac and cerebrovascular events (MACCE) (P value=0.13, 95% CI [0.48,1.10]), hospitalization for heart failure (P value=1.00, 95% CI [0.83,1.20]), and cardiac death (P value=0.91, 95% CI [0.73,1.32]). Conclusion The adjunctive application of RIC to PCI during treatment of STEMI patients showed a beneficial effect only on short-term reduction of myocardial infarct size, nevertheless, it was not of benefit regarding the other short and long-term metrics of myocardial salvage and left ventricular function.