Abciximab/Heparin Therapy for Left Ventricular Assist Device Implantation in Patients With Heparin-Induced Thrombocytopenia

Abstract

Background: Optimal anticoagulation strategy remains uncertain in patients with heparin-induced thrombocytopenia (HIT) and undergoing left ventricular assist device (LVAD) implantation. We describe our protocol of abciximab and heparin in these patients.

Methods: Our protocol is to administer abciximab, 0.25 mg/kg loading dose, followed by continuous infusion of 0.125 μg · kg^-1 · min^-1 throughout cardiopulmonary bypass. Full-dose heparin is then given with subsequent additional doses to maintain an activated clotting time of 400 seconds or longer. The abciximab infusion is stopped 15 minutes after heparin reversal with protamine, and platelets are transfused.

Results: Six patients underwent LVAD implantation with this protocol in our program. HIT was confirmed in 4 patients was suspected in 2, which was negative after the operation. One patient received a HeartMate XVE (Thoratec Corp, Pleasanton, CA) and the others received HeartMate II (Thoratec Corp). There were no thromboembolic complications. One patient required chest reexploration for bleeding and temporary right VAD support. Postoperative anticoagulation with argatroban was restarted on median postoperative day 3 (range, days 1 to 6) and warfarin was started on day 5 (range, days 3 to 12). Median postoperative intensive care unit stay was 9 days (range, 5 to 76 days), and hospital stay was 22 days (range, 18 to 132 days). After the initial LVAD implantation, 1 patient required HeartMate XVE LVAD exchange to HeartMate II and subsequent heart transplant, both of which were performed with the abciximab/heparin protocol. A HeartMate II device was explanted in another patient after myocardial recovery. The remaining 4 patients are alive on device support.

Conclusions: This is the first report of a novel abciximab/heparin protocol for LVAD implantation in patients with HIT. The preliminary results suggest the feasibility and safety of this protocol.