A single dose of recombinant factor VIIa (10-40 microg/kg) reduced INR to ≤1.5 within 10 minutes in all 7 patients with CNS bleeding on VKA therapy, and all patients survived.
Case Report (n=7)
Does recombinant factor VIIa reduce INR in patients with central nervous system bleeding during vitamin-K antagonist treatment?
Recombinant factor VIIa rapidly and effectively reverses elevated INR in patients with VKA-associated CNS bleeding without apparent thromboembolic complications.
Major bleeding is a frequent and hazardous complication associated with thromboprophylaxis using vitamin-K antagonists (VKA). Suggested regimens for control of highly elevated International Normalized Ratio (INR) and hemorrhagic events during VKA treatment include administration of vitamin K, infusion of fresh frozen plasma (FFP) or a prothrombin complex concentrate (PCC). In contrast, this communication present the first report on the efficacious use of recombinant factor VIIa (rFVIIa) as additional therapy in seven patients presenting with central nervous system (CNS) bleeding emergencies. Pre-treatment INRs ranged from 1.7 to 6.6, and 10 min after a single dose of rFVIIa (10-40 microg/kg) all INRs were </= 1.5. Six patients underwent drainage of the CNS hematoma and all patients survived. No untoward biochemical signs of coagulation activation were detected and no incidence of thromboembolism was observed. In ex-vivo experimental studies, profiles of continuous whole blood clot formation were evaluated by thrombelastography in 25 patients on VKA treatment (INR 1.7-4.3), demonstrating a significantly prolonged initiation phase and diminished propagation of clot formation. Ex-vivo supplementation with rFVIIa to blood of six patients returned a distinct reduction of the prolonged initiation but variable changes in the maximum velocity of clot formation. The ex-vivo experiments and our clinical data support recent suggestions that rFVIIa might substitute for infusion of FFP or PCC in acute reversal of VKA treatment.
Sørensen et al. (Tue,) conducted a case report in Central nervous system bleeding during warfarin thromboprophylaxis (n=7). Recombinant activated factor VII (rFVIIa) was evaluated on Reduction of INR to <= 1.5 at 10 minutes. A single dose of recombinant factor VIIa (10-40 microg/kg) reduced INR to ≤1.5 within 10 minutes in all 7 patients with CNS bleeding on VKA therapy, and all patients survived.