title: Impact of time to treatment on myocardial reperfusion and infarct size with primary percutaneous coronary intervention for acute myocardial infarction (from the EMERALD Trial).
abstract: The impact of time to treatment on outcomes after primary percutaneous coronary intervention (PCI) is controversial, and there are few data about time to treatment and infarct size. The EMERALD trial randomly assigned 501 high-risk patients with ST-elevation myocardial infarction undergoing primary PCI to stenting with or without GuardWire (Medtronic, Santa Rosa, California) distal protection. Infarct size using sestamibi imaging at 5 to 14 days and clinical outcomes were examined by time to treatment. There were no differences in outcomes between distal protection and control patients. Shorter time to reperfusion (<2 vs 2 to 3 vs >3 to 4 vs >4 hours) was associated with smaller infarct size (2% vs 9% vs 12% vs 11%, p=0.026), trends for better myocardial blush (p=0.08), and lower 6-month mortality rates (0% vs 0% vs 2.4% vs 5.3%, p=0.06). Incremental delays in reperfusion after 2 hours had little impact on infarct size. Shorter time to reperfusion impacted on infarct size in patients with anterior infarction (0% vs 17% vs 20.5% vs 30.5%, p=0.026), but not nonanterior infarction (3% vs 7% vs 7.5% vs 10%, p=0.23, p=0.022 for interaction). In conclusion, very early reperfusion with primary PCI is associated with smaller infarct size and has a much greater impact in anterior versus nonanterior infarction. Incremental delays in reperfusion after 2 hours have less effect on infarct size. These data have implications regarding the triage of patients for primary PCI.
authors.affiliation: LeBauer Cardiovascular Research Foundation and Moses Cone Heart and Vascular Center, Greensboro, North Carolina, USA. bbrodie@triad.rr.com
authors.forename: Bruce R
authors.initials: BR
authors.lastname: Brodie
authors.forename: John
authors.initials: J
authors.lastname: Webb
authors.forename: David A
authors.initials: DA
authors.lastname: Cox
authors.forename: Mansoor
authors.initials: M
authors.lastname: Qureshi
authors.forename: Anna
authors.initials: A
authors.lastname: Kalynych
authors.forename: Mark
authors.initials: M
authors.lastname: Turco
authors.forename: Heinz P
authors.initials: HP
authors.lastname: Schultheiss
authors.forename: Daniel
authors.initials: D
authors.lastname: Dulas
authors.forename: Barry
authors.initials: B
authors.lastname: Rutherford
authors.forename: David
authors.initials: D
authors.lastname: Antoniucci
authors.forename: Tom
authors.initials: T
authors.lastname: Stuckey
authors.forename: Mitch
authors.initials: M
authors.lastname: Krucoff
authors.forename: Raymond
authors.initials: R
authors.lastname: Gibbons
authors.forename: Alexandra
authors.initials: A
authors.lastname: Lansky
authors.forename: Yingbo
authors.initials: Y
authors.lastname: Na
authors.forename: Roxana
authors.initials: R
authors.lastname: Mehran
authors.forename: Gregg W
authors.initials: GW
authors.lastname: Stone
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D003326:Coronary Circulation / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*; D015425:Myocardial Reperfusion; D009206:Myocardium / Q000473:pathology*; D011446:Prospective Studies; D013997:Time Factors; D016896:Treatment Outcome