title: Effects of the early administration of heparin in patients with ST-elevation myocardial infarction treated by primary angioplasty.
abstract: BACKGROUND
  The effect of adjunctive heparin for primary angioplasty in patients with ST-elevation myocardial infarction (STEMI) is not well established, so the authors investigated the effect of early heparin administration in the emergency room (ER) on initial patency of the infarct-related artery (IRA) and on the clinical outcome in STEMI patients.
  
  
  RESULTS
  One hundred and twenty consecutive patients who presented with STEMI less than 12 h from pain onset and who were eligible for primary percutaneous coronary intervention were allocated to an early heparin group (heparin administered in ER) or a late heparin group (heparin administered after angiography). In the early heparin group, unfractionated heparin (60 U/kg bolus IV, then 14 U . kg(-1) . h(-1) IV infusion) or enoxaparin (1 mg/kg bolus SC) were administered 144+/-95 min before angioplasty. No significant differences in baseline characteristics were observed between the early heparin group (n=56) and the late heparin group (n=64). However, initial Thrombolysis In Myocardial Infarction (TIMI) flow grade in the IRA was significantly different between the 2 groups (frequency of TIMI 0/1/2/3; 48/4/7/41% vs 70/8/11/11%, early vs late respectively, p=0.002). TIMI 2 or 3 flow was significantly more frequent in the early heparin group than in the late heparin group (48% vs 22%, p=0.002). However, no significant differences were noted between the 2 groups in terms of in-hospital major adverse cardiac events (7% vs 11%, p=0.472) and TIMI major bleeding (2% vs 3%, p=0.639).
  
  
  CONCLUSIONS
  In STEMI patients, early heparin therapy administered in the ER improves coronary patency, despite not reaching clinical benefit.
authors.affiliation: Cardiovascular Center, Seoul National University Bundang Hospital, 300 Gumi-dong, Dungang-gu, Seongnam-si, Gyeonggi-do 463-707, South Korea.
authors.forename: Woo-Young
authors.initials: WY
authors.lastname: Chung
authors.forename: Mi-Jung
authors.initials: MJ
authors.lastname: Han
authors.forename: Young-Seok
authors.initials: YS
authors.lastname: Cho
authors.forename: Kwang-Il
authors.initials: KI
authors.lastname: Kim
authors.forename: Hyuk-Jai
authors.initials: HJ
authors.lastname: Chang
authors.forename: Tae-Jin
authors.initials: TJ
authors.lastname: Youn
authors.forename: In-Ho
authors.initials: IH
authors.lastname: Chae
authors.forename: Dong-Ju
authors.initials: DJ
authors.lastname: Choi
authors.forename: Cheol-Ho
authors.initials: CH
authors.lastname: Kim
authors.forename: Byung-Hee
authors.initials: BH
authors.lastname: Oh
authors.forename: Young-Bae
authors.initials: YB
authors.lastname: Park
authors.forename: Yun-Shik
authors.initials: YS
authors.lastname: Choi
mesh_terms: D000800:Angioplasty, Balloon; D000925:Anticoagulants / Q000008:administration & dosage*; D017984:Enoxaparin / Q000008:administration & dosage*; D005260:Female; D006493:Heparin / Q000008:administration & dosage*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000401:mortality / Q000628:therapy*; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D000925:Anticoagulants; D017984:Enoxaparin; D006493:Heparin