Evaluation of Patients with Ineffective Anticoagulation after Left Ventricular Assist Device (LVAD) Implantation: Early and mid term follow up

Abstract

Reports about discontinuation of anticoagulant therapy in LVAD patients are very limited. We reported that our experience of discontinuation of warfarin and aspirin therapy due to bleeding and ineffective international normalized ratio (INR) in patients with LVAD. From June 2013 to June 2019, hundred and forty seven patients that underwent LVAD implantation at our department. We analyzed outcomes of patients in whom warfarin and aspirin therapy had to be discontinued due to bleeding and temporary warfarin resistance during ongoing support with LVAD. None of these patients received any anticoagulation therapy until their bleeding event was over. INR <2 was defined as ineffective INR. We collected baseline and follow-up data, including patient characteristics, history of atrial fibrillation, history of heparin-induced thrombocytopenia, renal function at time of discontinuation. We checked speed, flow rates and power consumption parameters of pump, lactate dehydrogenase (LDH), creatinine, total bilirubin and INR level daily. After patients were discharged from the hospital, they returned to our center for follow-up, device review and clinical assessment. Of thirty five (23.8%) patients, mean age was 41 ± 16 (19-65) years, mean follow up time was 645.7 ± 430 (52-1315) days. Thirty patients had to discontinue warfarin due to bleeding and ineffective INR due to warfarin resistance in five patients. Mean duration of ineffective INR was 24.5 ± 12.1 (9-45) days. In one of the patient with intracranial hemorrhage, pump thrombosis was encountered, and his pump had to be exchanged with an urgent operation. There were not any other adverse events in this patient population. Mean follow-up time after ineffective INR situation was 344 ± 417 (94-1240) days. No delayed rehemorrhages or pump complications were observed after resuming aspirin and warfarin therapy. Despite advances in device technology and treatment strategies, prospective, controlled studies are needed to determine the new anticoagulation regimen that most effectively balances bleeding and thrombosis in LVAD patients.