title: Correlations between epicardial flow, microvascular reperfusion, infarct size and clinical outcomes in patients with anterior versus non-anterior myocardial infarction treated with primary or rescue angioplasty: analysis from the EMERALD trial.
abstract: OBJECTIVE
  We compared epicardial and microvascular reperfusion, infarct size, and clinical outcomes after primary and rescue PCI with and without GuardWire distal protection in patients with LAD vs. non-LAD acute myocardial infarction (AMI). In the general AMI population undergoing primary PCI, the use of GuardWire did not yield higher reperfusion success, reduced infarct size, or enhanced event-free survival. Whether GuardWire is beneficial in patients with AMI in certain territories of the coronary circulation is unknown.
  
  
  RESULTS
  In the EMERALD trial, 501 patients with AMI were randomised to PCI with vs. without distal protection. The outcomes were analysed as a function of culprit vessel (LAD vs. non-LAD) and the use of GuardWire. Patients with LAD vs. non-LAD infarcts had significantly (P< or =0.0001) lower rates of final TIMI flow grade 3 (85.2% vs. 94.4%), myocardial blush grade 3 (40.1% vs. 67.6%), and complete ST-segment resolution (35.1% vs. 79.6%). Patients with LAD infarcts also had larger infarct size (25.8+/-21.8% vs. 11.3_13.7%, p<0.0001) and a trend towards higher rates of 6-month mortality (5.5% vs. 2.1%, p=0.09) and new-onset severe heart failure (3.5% vs. 1.1%, p=0.08). Rates of reperfusion were not related to GuardWire use in patients with LAD infarcts. In patients with non-LAD infarcts, the use of GuardWire was associated with a trend towards better epicardial and microvascular reperfusion.
  
  
  CONCLUSIONS
  Myocardial infarction in the territory of the LAD is associated with worse epicardial and microvascular reperfusion and worse 6-month clinical outcomes. Use of the GuardWire showed a trend towards better epicardial and microvascular flow in patients with a non-LAD infarct-related artery.
authors.affiliation: Columbia University Medical Center, New York, NY, USA. enikolsky@gmail.com
authors.forename: Eugenia
authors.initials: E
authors.lastname: Nikolsky
authors.forename: Gregg W
authors.initials: GW
authors.lastname: Stone
authors.forename: Edwin
authors.initials: E
authors.lastname: Lee
authors.forename: Alexandra J
authors.initials: AJ
authors.lastname: Lansky
authors.forename: John
authors.initials: J
authors.lastname: Webb
authors.forename: David A
authors.initials: DA
authors.lastname: Cox
authors.forename: Bruce R
authors.initials: BR
authors.lastname: Brodie
authors.forename: Mark A
authors.initials: MA
authors.lastname: Turco
authors.forename: Barry D
authors.initials: BD
authors.lastname: Rutherford
authors.forename: Anna M
authors.initials: AM
authors.lastname: Kalynych
authors.forename: David
authors.initials: D
authors.lastname: Antoniucci
authors.forename: Mitchell W
authors.initials: MW
authors.lastname: Krucoff
authors.forename: Raymond J
authors.initials: RJ
authors.lastname: Gibbons
authors.forename: Martin
authors.initials: M
authors.lastname: Fahy
authors.forename: Roxana
authors.initials: R
authors.lastname: Mehran
mesh_terms: D000368:Aged; D017130:Angioplasty / Q000379:methods; D015906:Angioplasty, Balloon, Coronary / Q000379:methods*; D001794:Blood Pressure; D001919:Bradycardia / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D009203:Myocardial Infarction / Q000401:mortality / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D011183:Postoperative Complications / Q000453:epidemiology; D016032:Randomized Controlled Trials as Topic; D015607:Stents; D016019:Survival Analysis; D017741:Survivors; D013610:Tachycardia / Q000453:epidemiology; D017211:Treatment Failure; D016896:Treatment Outcome