Objective: To investigate efficacy and safety of enoxaparin for catheter-related arterial thrombosis in infants with congenital heart disease. Design: Prospective observational study. Setting: Pediatric Intensive Care and Cardiology Unit at the University Children's Hospital of Zurich. Patients: Acohort of 32 infants aged 0-12 months treated with enoxaparin for catheter-related arterial thrombosis from 2002 to 2005. Measurements: Dose requirements of enoxaparin, resolution of thrombosis by Doppler ultrasound, and bleeding complications. Results: Catheter-related arterial thrombosis was located in the iliac/femoral arteries in 31 (97%) infants and aorta in 1 infant, and was related to indwelling catheters and cardiac catheterization in 17 (53%) and 15 (47%) cases, respectively. Newborns required increased doses of enoxaparin to achieve therapeutic anti-FXa levels (mean 1.62 mg/kg per dose) compared with infants aged 2-12 months (mean 1.12 mg/kg per dose; p = 0.0002). Complete resolution of arterial thrombosis occurred in 29 (91%) infants at amean of 23 days after initiation of enoxaparin therapy. Partial or no resolution was observed in 1 (3%) and 2 (6%) infants, respectively, at amean follow-up time of 4.3 months. Bleeding complications occurred in 1 (3%) infant. Conclusion: Enoxaparin is efficient and safe for infants with congenital heart disease and catheter-related arterial thrombosis, possibly representing avalid alternative to the currently recommended unfractionated hepari
