Design of the study:
Prospective, in vitro coagulation study
 

Methods:
-Blood from 7 pts for valve/CABG under cardiopulmonary bypass vs. from 7 healthy pts.
-In vitro coagulation with rFVII and fibrinogen concentrate using viscoelastic measurements of fibrin formation and fluorogenic measurments of thrombin generation.
-Heparin or tissue plaminogen activator were added to the blood of volunteers to simulate residual heparin effect sometimes observed after protamine administration
-Samples treated with either saline, fibrinogen, rFVIIa or fibrinogen plus rFVIIa
 

Results:
-rFVIIa significantly decreased the time to onset of clot formation (CT) but did not affect maximum clot firmness (MCF)
-Fibrinogen did not affect CT but increased MCF
-When both were added, CT and MCF significantly increased
-CT and MCF were most improved when treated with both agents
-Lag time was decreased and peak thrombin generation increased only by rFVIIa but not fibrinogen
 

Conclusion/take home message:
-rFVIIa and fibrinogen combination improved stability and onset of thrombus formation
-rFVIIa increased generation of fibrin and thrombin
-Only fibrinogen improved fibrin clot strength