Deferred Versus Immediate Stenting in Patients With ST‐Segment Elevation Myocardial Infarction: A Systematic Review and Meta‐Analysis

BACKGROUND A number of studies have evaluated the efficacy of deferred stenting vs immediate stenting in patients with ST-segment elevation myocardial infarction, but the findings were not consistent across these studies. This meta-analysis aims to assess optimal treatment strategies in patient with ST-segment elevation myocardial infarction. METHODS AND RESULTS We searched the PubMed, EMBASE, and the Cochrane Library for studies that assessed deferred vs immediate stenting in patients with ST-segment elevation myocardial infarction. Nine studies including 1456 patients in randomized controlled trials and 719 patients in observational studies were included in the meta-analysis. No significant differences were observed in the incidence of no- or slow-reflow between deferred stenting and immediate stenting in randomized controlled trials (odds ratio [OR] 0.51, 95%CI 0.17-1.53, P=0.23, I2=70%) but not in observational studies (OR 0.13, 95%CI 0.06-0.31, P<0.0001, I2=0%). Deferred stenting was associated with an increase in long-term left ventricular ejection fraction (weighted mean difference 1.90%, 95%CI 0.77-3.03, P=0.001, I2=0%). No significant differences were observed in the rates of major adverse cardiovascular events (OR 0.53, 95%CI 0.27-1.01, P=0.06 [randomized OR 0.98, 95%CI 0.73-1.30, P=0.87, I2=0%; nonrandomized OR 0.30, 95%CI 0.15-0.58, P=0.0004, I2=0%]), major bleeding (OR=0.1.61, 95%CI 0.70-3.69, P=0.26, I2=0%), death (OR=0.78, 95%CI 0.53-1.15, P=0.22, I2=0%), MI (OR=0.97, 95%CI 0.34-2.78, P=0.96, I2=35%) and target vessel revascularization (OR 0.97, 95%CI 0.40-2.37, P=0.95, I2=24%), between deferred and immediate stenting. CONCLUSIONS Compared with immediate stenting, a deferred-stenting strategy did not reduce the occurrence of no- or slow-reflow, death, myocardial infarction, or repeat revascularization compared with immediate stenting in patients with ST-segment elevation myocardial infarction, but showed an improved left ventricular function in the long term.