Faculty Bibliography

BACKGROUND: Direct factor (F)Xa inhibition is an attractive method to limit thrombotic complications during percutaneous coronary intervention (PCI). OBJECTIVES: To investigate drug levels achieved, effect on coagulation markers, and preliminary efficacy and safety of several doses of DX-9065a, an intravenous, small molecule, direct, reversible FXa inhibitor during PCI. PATIENTS AND METHODS: Patients undergoing elective, native-vessel PCI (n = 175) were randomized 4 : 1 to open-label DX-9065a or heparin in one of four sequential stages. DX-9065a regimens in stages I-III were designed to achieve concentrations of > 100 ng mL-1, > 75 ng mL-1, and > 150 ng mL-1. Stage IV used the stage III regimen but included patients recently given heparin. RESULTS: At 15 min median (minimum) DX-9065a plasma levels were 192 (176), 122 (117), 334 (221), and 429 (231) ng mL-1 in stages I-IV, respectively. Median whole-blood international normalized ratios (INRs) were 2.6 (interquartile range 2.5, 2.7), 1.9 (1.8, 2.0), 3.2 (3.0, 4.1), and 3.8 (3.4, 4.6), and anti-FXa levels were 0.36 (0.32, 0.38), 0.33 (0.26, 0.39), 0.45 (0.41, 0.51), and 0.62 (0.52, 0.65) U mL-1, respectively. Stage II enrollment was stopped (n = 7) after one serious thrombotic event. Ischemic and bleeding events were rare and, in this small population, showed no clear relation to DX-9065a dose. CONCLUSIONS: Elective PCI is feasible using a direct FXa inhibitor for anticoagulation. Predictable plasma drug levels can be rapidly obtained with double-bolus and infusion DX-9065a dosing. Monitoring of DX-9065a may be possible using whole-blood INR. Direct FXa inhibition is a novel and potentially promising approach to anticoagulation during PCI that deserves further study

BACKGROUND: Direct angioplasty (PTCA) and thrombolytic therapy are the chief therapies for treating an ST-segment elevation myocardial infarction (MI). OBJECTIVE: This study was designed to evaluate sex differences in the relative benefit of direct PTCA versus thrombolytic therapy among patients enrolled in the Global Use of Strategies to Open Occluded Arteries in Acute Coronary Syndromes Angioplasty (GUSTO II-B PTCA) Substudy. METHODS: Women and men presenting with an acute ST-segment elevation MI were randomized to receive either direct PTCA or accelerated tissue plasminogen activator (t-PA). Patients were then randomized to treatment with either heparin or bivalirudin. A gender analysis of outcome was performed. RESULTS: Women were older than men (68.6 +/- 11.5 vs 59.5 +/- 12.0 years, P <.001) and were more likely to have diabetes (22.5% vs 13.5%, P <.0001) and hypertension (53.3% vs 34.8%, P =.001). After adjusting for differences in baseline variables, the odds ratio (OR) for reaching a 30-day clinical end point (death, nonfatal infarction, or nonfatal disabling stroke) was similar for women and men (1.35, 95% CI 0.88-2.08). The OR for reaching a clinical end point at 30 days for the PTCA-treated women compared with the t-PA-treated women was 0.685 (95% CI 0.36-1.32) and similar to the OR in men, 0.565 (95% CI 0.35-0.91), P for interaction =.535. Because women had a higher event rate than men, the absolute number of major events prevented when treating women with direct PTCA was higher than men (56 events/1000 women treated with PTCA vs 42 events per 1000 men treated with PTCA). CONCLUSIONS: Although the relative benefit of direct PTCA to t-PA for the treatment of an acute MI appears to be similar in women and men, women may derive a larger absolute benefit from direct PTCA