Subcutaneous enoxaparin with early invasive strategy in patients with acute coronary syndromes.

BACKGROUND: Subcutaneous enoxaparin during at least 48 hours provides adequate anticoagulation and good clinical results in patients with non-ST-segment elevation acute coronary syndromes undergoing percutaneous coronary intervention (PCI).

METHODS: In this nonrandomized retrospective study, we compared 347 patients with non-ST-segment elevation acute coronary syndromes who underwent rapid PCI after only 2 injections of subcutaneous enoxaparin (EI, n = 117) to those referred later to the catheterization laboratory with >or=3 injections (DI, n = 230). We measured anti-Xa at the time of PCI and evaluated bleeding and major ischemic events (death/myocardial infarction) at 30 days.

RESULTS: Patients in the EI group more frequently received glycoprotein IIb/IIIa inhibitors and clopidogrel preceding PCI than did patients in the DI group (58.1% vs 31.7%, P <.0001 for glycoprotein IIb/IIIa inhibitors and 68.4% vs 40.4% for clopidogrel pretreatment, P <.0001, respectively). The anti-Xa activity measured at the time of catheterization (0.92 +/- 0.04 U/mL vs 0.96 +/- 0.02 U/mL, EI vs DI, P =.25) and the injection-to-catheterization times (5.6 +/- 0.2 h vs 5.2 +/- 0.1 h, EI vs DI, P =.17) were similar in both groups. The 30-day bleeding rates of 1.7% and 4.8% in the EI and DI strategies were found to be equivalent with a significant non-inferiority test for the EI strategy (P <.05). There was a nonsignificant trend for less death or myocardial infarction at 30 days in the EI group compared to the DI group (4.3% vs 7.0%, non-inferiority test not significant).

CONCLUSION: A rapid invasive strategy with only 2 subcutaneous injections of enoxaparin provides similar levels of anticoagulation, and is associated with a favorable trend for ischemic events and with safety equivalent to a more prolonged "upstream" treatment with enoxaparin.