Primary PCI for ST-segment elevation myocardial infarction in a patient treated with subcutaneous enoxaparin utilizing point-of-care Enox test.

The superiority of enoxaparin compared with unfractionated heparin in the medical management of patients with non-ST elevation acute coronary syndromes (NSTE ACS) has been demonstrated in clinical trials. Further, enoxaparin has been shown to be safe and effective during PCI, including in combination with glycoprotein IIb/IIIa inhibitors. Whether enoxaparin is superior to unfractionated heparin in patients with NSTE ACS under-going early invasive strategy is currently being tested in a large clinical trial. Data on the use of enoxaparin in patients undergoing primary angioplasty for ST-segment elevation myocardial infarction are limited. Unlike patients who present to the catheterization laboratory after several doses of enoxaparin where in a steady state anticoagulation might have been achieved, patients who present early after administration of a single dose of subcutaneous enoxaparin may not have an adequate level of anticoagulation for PCI. The ability to monitor activity of enoxaparin in such patients using a point-of-care test might be useful. This report describes a patient with ST-segment elevation myocardial infarction who presented for primary angioplasty 75 minutes after administration of subcutaneous enoxaparin. The Rapidpoint Enox test measured 135 seconds and the patient's corresponding serum anti-Xa level was 0.12 IU/mL indicating a suboptimal level of anticoagulation for PCI. Procedural success was attained using additional 0.3-mg/kg intravenous enoxaparin.