title: Deferred versus conventional stent implantation in patients with acute ST-segment elevation myocardial infarction: An updated meta-analysis of 10 studies.
abstract: BACKGROUND
  We sought to evaluate safety and efficacy of the deferred stenting versus immediate stent implantation of infarct-related arteries in patients with acute ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI).
  
  
  METHODS
  A meta-analysis using random-effects models were conducted. The primary outcome, major adverse cardiac events (MACE), was a composite of all-cause mortality, myocardial infarction (MI), any unplanned target vessel revascularization (TVR), and hospitalization due to cardiac cause. Periprocedural composite events were composed of acute re-occlusion, no-reflow/slow flow, or distal embolization.
  
  
  RESULTS
  Seven non-randomized registries and three randomized trials comparing outcomes of deferred versus immediate stenting in infarct-related arteries of 2281 STEMI patients were selected. Risk of MACE between deferred or immediate stenting did not differ significantly (rates, 12.8% vs 15.0%; pooled RR=0.68, 95% CI: 0.43-1.06; p=0.087; I2=26.8%). Deferred stenting was associated with significantly reduced risk of periprocedural composite events (rates, 5.3% vs 10.2%; pooled RR=0.36, 95% CI: 0.18-0.69; p=0.002; I2=68.0%) and flow abnormality in infarct-related arteries (rates, 3.8% vs 8.4%; pooled RR=0.29, 95% CI: 0.14-0.61; p=0.001; I2=58.1%). However, clinical outcomes including all-cause mortality, MI, or any unplanned TVR, were unaffected. Meta-regression indicated a significant relationship between prolonged total ischemic and reduced risk of MACE after deferred stenting (OR=0.994, 95% CI: 0.990-0.998; p=0.027; I2residual 0.0%, adjusted R2=100.0%).
  
  
  CONCLUSIONS
  Although deferred stenting carried significantly lower risk of periprocedural composite events and abnormal flow in patients undergoing primary PCI for STEMI, such benefits had no impact on MACE, which did not differ significantly by timing of stent placement.
authors.affiliation: Department of Internal Medicine and Cardiovascular Center, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine.
authors.forename: Joo Myung
authors.initials: JM
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine and Cardiovascular Center, Seoul National University Hospital, Seoul, Republic of Korea.
authors.forename: Tae-Min
authors.initials: TM
authors.lastname: Rhee
authors.affiliation: Department of Internal Medicine and Cardiovascular Center, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine.
authors.forename: Haseong
authors.initials: H
authors.lastname: Chang
authors.affiliation: Division of Biostatistics, Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, MD, USA.
authors.forename: Chul
authors.initials: C
authors.lastname: Ahn
authors.affiliation: Department of Internal Medicine and Cardiovascular Center, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine.
authors.forename: Taek Kyu
authors.initials: TK
authors.lastname: Park
authors.affiliation: Department of Internal Medicine and Cardiovascular Center, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine.
authors.forename: Jeong Hoon
authors.initials: JH
authors.lastname: Yang
authors.affiliation: Department of Internal Medicine and Cardiovascular Center, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine.
authors.forename: Young Bin
authors.initials: YB
authors.lastname: Song
authors.affiliation: Department of Internal Medicine and Cardiovascular Center, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine.
authors.forename: Seung-Hyuk
authors.initials: SH
authors.lastname: Choi
authors.affiliation: Department of Internal Medicine and Cardiovascular Center, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine.
authors.forename: Hyeon-Cheol
authors.initials: HC
authors.lastname: Gwon
authors.affiliation: Department of Internal Medicine and Cardiovascular Center, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine. Electronic address: jyhahn@skku.edu.
authors.forename: Joo-Yong
authors.initials: JY
authors.lastname: Hahn
mesh_terms: D006801:Humans; D062645:Percutaneous Coronary Intervention; D000072657:ST Elevation Myocardial Infarction / Q000601:surgery*; D015607:Stents; D013997:Time Factors; D016896:Treatment Outcome
keywords: Meta-analysis; No reflow; Outcomes; Percutaneous coronary intervention; ST-segment elevation myocardial infarction