8549 Background: Timing and frequency of non occlusive (nO) or occlusive (O) CVCrT in cancer patients (pts) remain unclear. In this randomized controlled trial we studied these points and evaluated the efficacy and safety of short-term prophylaxis with A or D in the prevention of CVCrT. Methods: Consecutive cancer pts without contraindications to short-term anticoagulation, scheduled for chemotherapy via CVC, were randomly assigned to receive: A 1 mg/day for 3 days before and 8 days after CVC insertion; D 5,000 IU 2 hours before and daily for 8 days after CVC insertion; no anticoagulant treatment (NT). All pts underwent venography (V) at day 8 and 30 after CVC insertion and then every two months until CVC removal . The primary endpoint was V detected CVCrT, evaluated as nO or O when it was partially or completely occlusive of the vein lumen, respectively. Bleeding episodes were recorded. Proportions were compared using chi-square test together with odds ratio (OR). Results: 450 pts were randomized, 348 of whom (120/150 A, 114/150 D, and 114/150 NT) underwent V (median number of procedures 4, range 2–8). Both A and D reduced the frequency of V detected CVCrT (21.9% A vs 55.3% NT, OR= 4.35 (95% CI 2.43–7.69), p<0.001; 40% D vs 55.3% NT, OR= 1.85 (95% CI 1.10–3.13), p=0.02). A was more effective than D (OR= 2.37 (CI 1.34–4.22), p= 0.003). The frequency of O CVCrT was not different in the 3 groups (0.9% A, 5.0% D, 4.4% NT; p= 0.18). Overall, 5.1% of pts with CVCrT were symptomatic, all presenting O CVCrT (42% of pts with O CVCrT were not symptomatic). Most CVCrTs (95.6%) were observed at day 8 after CVC insertion. No major bleeding or pulmonary embolism occurred. Conclusions: In this study, acenocumarine was more effective than dalteparine in reducing V detected CVCrT. The doses of prophylactic agents used in this study proved to be safe. Symptomatic CVCrT evaluation alone underestimates the actual CVCrT frequency. The first days following CVC insertion are at highest risk for CVCrT. Short term thrombosis prophylaxis appears to be superior to no treatment without the expenses and inconveniences inherent in long-term prophylaxis. No significant financial relationships to disclose.
Early and short-term acenocumarine or dalteparin for the prevention of central vein catheter-related thrombosis in cancer patients: a randomized controlled study based on serial venographies
