Use of enoxaparin to diminish the incidence of vascular access stenosis/thrombosis in chronic hemodialysis patients

Abstract

Enoxaparin, a low molecular weight heparin, has been shown to be a safe and effective anticoagulant to prevent clotting in the extracorporeal circulation during hemodialysis. Enoxaparin also possesses antiproliferative properties, and reduces neointimal proliferation following vascular injury in animals. Use of enoxaparin during hemodialysis may be associated with decreased myointimal proliferation and diminished vascular access stenosis or failure. The aim of our study was to test the efficacy of enoxaparin to reduce the incidence of recurrent vascular access stenosis in chronic hemodialysis patients. Twenty-nine hemodialysis patients who suffered from recurrent arteriovenous (A-V) access stenosis were studied retrospectively to compare the incidence of vascular access procedures before and during enoxaparin administration. Enoxaparin was administered intravenously as a single bolus at the start of hemodialysis. Twenty-eight patients (14 male) were analyzed. Ten required a new fistula during the study period. Observed treatment times (years/patient) were 1.20 ± 0.87 for unfractionated heparin (UFH) and 3.04 ± 2.19 for enoxaparin (P = 0.0001). Angiographic procedure rates (procedures/year) were 1.76 ± 0.92 in the UFH group and 1.30 ± 1.01 in the enoxoparin group (P = 0.0786). There were no significant differences in time to first stenosis between the two groups (P = 0.5315). One patient receiving enoxaparin developed upper gastrointestinal bleeding and a second patient sustained a subdural hematoma after a fall. Our study demonstrated a trend toward a decreased number of angiographic procedures for maintaining A-V access patency in selected chronic hemodialysis patients treated with enoxaparin in comparison with UFH as anticoagulant during dialysis.