Clin Res Cardiol 98, Suppl 1, April 2009

V1616 - Bridging of OralAnticoagulation with Low Molecular Weight Heparin: Experience in 367 Patients with Renal Insufficiency Undergoing Invasive Procedures
C. Hammerstingl1, H. Omran2
1Medizinische Klinik und Poliklinik II, Universitätsklinikum Bonn, Bonn; 2Innere Medizin, St.Marien-Hospital Bonn, Bonn;
Background: Current guidelines recommend bridging oral anticoagulation (OAC) with heparins in patients at elevated thromboembolic (TE) risk.  Patients with renal impairment have a higher risk of bleeding and dosing of heparins is more difficult. However, approximately one third of patients with symptomatic cardiovascular disease suffer from renal impairment. The current guidelines do not provide recommendation for bridging the latter patients. Hence, we aimed to investigate the efficacy and safety of using reduced LMWH dosages (enoxaparin) for bridging chronically anticoagulated patients with renal insufficiency.
Methods and results: 316 hospitalised and 51 ambulatory adult patients at thromboembolic risk requiring bridging therapy were enrolled. Patients with renal insufficiency (n=264 with CrCl < 50-30 mL/min and n= 103 with CrCl 20-29 mL/min) received after discontinuation of OAC therapy enoxaparin 1mg/kg once daily. Surgery was performed at an INR < 1.5. Thromboembolic or bleeding events were documented within 30 days of follow-up.
No case of thromboembolism was observed. Overall 27 bleeding events occurred (major bleeding n=3, minor bleedings n=33) and no case of heparin induced thrombocyto­penia (HIT-II) were reported. Patients with a CrCl < 30 ml/min had a significantly higher rate of bleeding as compared to those patients with a CrCl < 50-30 ml/min. The CHADS2 score was an independent risk factor of bleeding. Bridging therapy could be performed in 51 patients in an ambulatory manner.
Conclusion: In renally impaired patients undergoing bridging of OAC, a reduced dosage of enoxaparin was effective as indicated by the lack of thromboembolic events. It appeared safe, as the rate of major bleedings (0.5%) was low. However, minor bleedings are high (9%).