Effects of the early administration of heparin in patients with ST-elevation myocardial infarction treated by primary angioplasty.
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.
Chung
Woo-Young
WY
Cardiovascular Center, Seoul National University Bundang Hospital, 300 Gumi-dong, Dungang-gu, Seongnam-si, Gyeonggi-do 463-707, South Korea.
Han
Mi-Jung
MJ
Cho
Young-Seok
YS
Kim
Kwang-Il
KI
Chang
Hyuk-Jai
HJ
Youn
Tae-Jin
TJ
Chae
In-Ho
IH
Choi
Dong-Ju
DJ
Kim
Cheol-Ho
CH
Oh
Byung-Hee
BH
Park
Young-Bae
YB
Choi
Yun-Shik
YS
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
D000925:Anticoagulants; D017984:Enoxaparin; D006493:Heparin