Primary anticoagulation with bivalirudin for patients with implantable ventricular assist devices

Bivalirudin is a direct thrombin inhibitor that is increasingly used in patients undergoing mechanical circulatory support as it presents many advantages compared with unfractionated heparin. The aim of this study was to describe our experience with bivalirudin as primary anticoagulant in patients undergoing ventricular assist device (VAD) implantation. An observational study was performed on 12 consecutive patients undergoing VAD implantation at our institution. Patients received a continuous infusion of bivalirudin, with a starting dose of 0.025mg/kg/h; the target activated partial thromboplastin time (aPTT) was between 45 and 60s. Patients never received heparin during hospitalization nor had a prior diagnosis of heparin-induced thrombocytopenia (HIT). All patients received a continuous flow pump except one. Preoperative platelets count was 134000±64000 platelets/mm³. Mean bivalirudin dose was 0.040±0.026mg/kg/h over the course of therapy (5-12 days). Lowest platelets count during treatment was 73000±23000 platelets/mm³. No thromboembolic complications occurred. Two episodes of minor bleeding from chest tubes that subsided after reduction or temporary suspension of bivalirudin infusion were observed. Intensive care unit stay was 8 (7-17) days, and hospital stay was 25 (21-33) days. Bivalirudin is a valuable option for anticoagulation in patients with a VAD and can be easily monitored with aPTT. The use of a bivalirudin-based anticoagulation strategy in the early postoperative period may overcome many limitations of heparin and, above all, the risk of HIT, which is higher in patients undergoing VAD implantation. Bivalirudin should no longer be regarded as a second-line therapy for anticoagulation in patients with VAD. [Correction added on 6 December 2013, after first online publication: The dose of bivalirudin in the Abstract to 0.025 mg/kg/h].