April 9, 2002Circulation252 citations
View Full PaperEnoxaparin as Adjunctive Antithrombin Therapy for ST-Elevation Myocardial Infarction
Structured PICO
Does enoxaparin improve early coronary patency and reduce ischemic events compared to unfractionated heparin as adjunctive therapy in patients with STEMI receiving tenecteplase?
P
Population
483 patients with ST-elevation myocardial infarction (STEMI) presenting <6 hours from symptom onset
I
Intervention
Enoxaparin (1.0 mg/kg subcutaneously every 12 hours +/- initial 30 mg IV bolus with full-dose tenecteplase, or 0.3 to 0.75 mg/kg subcutaneously every 12 hours +/- initial 30 mg IV bolus with half-dose tenecteplase plus abciximab)
C
Comparator
Unfractionated heparin (bolus 60 U/kg; infusion 12 U/kg per hour with full-dose tenecteplase, or bolus 40 U/kg; infusion 7 U/kg per hour with half-dose tenecteplase plus abciximab)
O
Outcome
TIMI 3 flow at 60 minutessurrogate
In patients with STEMI receiving tenecteplase, adjunctive enoxaparin provides similar early coronary patency but significantly reduces 30-day ischemic events compared to unfractionated heparin, without increasing major bleeding when used with full-dose lytic therapy.
Abstract
BACKGROUND: ENTIRE-TIMI 23 evaluated enoxaparin with full-dose tenecteplase (TNK) and half-dose TNK plus abciximab. METHODS AND RESULTS: Patients (n=483) with ST-elevation MI presenting <6 hours from symptom onset were randomized to full-dose TNK and either unfractionated heparin (UFH) (bolus 60 U/kg; infusion 12 U/kg per hour) or enoxaparin (1.0 mg/kg subcutaneously every 12 hours+/-initial 30 mg intravenous bolus), or half-dose TNK plus abciximab and either UFH (bolus 40 U/kg; infusion 7 U/kg per hour) or enoxaparin (0.3 to 0.75 mg/kg subcutaneously every 12 hours+/-initial intravenous bolus of 30 mg). With full-dose TNK and UFH, the rate of TIMI 3 flow at 60 minutes was 52% and was 48% to 51% with enoxaparin. Using combination therapy, the rate of TIMI 3 flow was 48% with UFH and 47% to 58% with enoxaparin. The rate of TIMI 3 flow among all UFH patients was 50% and was 51% among enoxaparin patients. Through 30 days, death/recurrent MI occurred in the full-dose TNK group in 15.9% of patients with UFH and 4.4% with enoxaparin (P=0.005). In the combination therapy group, the rates were 6.5% with UFH and 5.5% with enoxaparin. The rate of major hemorrhage with full-dose TNK was 2.4% with UFH and 1.9% with enoxaparin; with combination therapy, it was 5.2% using UFH and 8.5% with enoxaparin. CONCLUSIONS: Enoxaparin is associated with similar TIMI 3 flow rates as UFH at an early time point while exhibiting advantages over UFH with respect to ischemic events through 30 days. These findings with enoxaparin are achieved with a similar risk of major hemorrhage.