Dm. Monroe et al., The factor VII-Platelet interplay: Effectiveness of recombinant factor VIIa in the treatment of bleeding in severe thrombocytopathia, SEM THROMB, 26(4), 2000, pp. 373-377
Recently, high-dose factor VIIa has been used to correct bleeding in patien
ts with various thrombocytopathias including Glanzmann's thrombasthenia, Be
rnard-Soulier syndrome, and uremia, High-dose factor Wa is postulated to ac
t on platelets in the absence of tissue factor to activate factors TX and X
and thus enhance thrombin generation, This enhanced thrombin generation mi
ght help provide hemostasis in patients with thrombocytopathias through sev
eral mechanisms, Enhanced thrombin generation would provide a strong signal
for recruitment of other platelets. Also, enhanced fibrin deposition might
provide mechanisms for bypassing the specific defect in thrombocytopathias
. Thus, platelets from a patient with Bernard-Soulier syndrome might associ
ate with fibrin by a glycoprotein IIb-IIIa-mediated mechanism, Also, platel
ets from a patient with Glanzmann's thrombasthenia might associate with fib
rin through von Willebrand factor-mediated interactions with glycoprotein I
b-V-M. Finally, enhanced thrombin generation on platelets would mean that f
ewer platelets are required for hemostasis.