Implantation of left ventricular assist devices under extracorporeal life support in patients with heparin-induced thrombocytopenia.

Abstract

Heparin-induced thrombocytopenia (HIT) is a rare but life-threatening side effect of heparin therapy. It is a demanding therapeutic challenge in patients undergoing left ventricular assist device (LVAD) implantation. We present our experience with LVAD implantation under extracorporeal life support (ECLS) in patients suffering from HIT. Seven patients (mean age 54.0 ± 16.7 years, 1 female, 6 male patients) suffering from acute heart failure were stabilized with ECLS. Under heparin therapy, they all showed a sudden decrease of mean platelet count (maximum 212.6 ± 41.5 tsd/μl; minimum 30.7 ± 13.1 tsd/μl). Due to the clinical suspicion of HIT anticoagulation was switched from heparin to argatroban (aPTT 70-80 s.). No improvement of cardiac function could be detected under ECLS, so LVAD implantation was indicated. We performed LVAD implantation under ECLS. During LVAD implantation under argatroban (aPTT of 50-60 s.) one patient developed massive intraventricular thrombus formations, so the device had to be removed. In 6 cases, we could successfully perform LVAD implantation under argatroban with a higher aPTT of 70-80 s and modified operative strategy. Four patients needed postoperative re-exploration because of bleeding complications. Perioperative management of LVAD patients under argatroban anticoagulation is very difficult. We were able to minimize the perioperative risk for thrombosis with a target aPTT of 70-80 s. To keep the phase of stasis within the device as short as possible we anastomosed the VAD outflow graft to the ascending aorta first before connecting the device to the apex. However, postoperative bleeding complications are frequent.