Severe Factor V deficiency in a 12-years old CHD patient with intracranial bleeding has been described by Ozkaya H et al.21 The raised von Willebrand factor antigen (vWF:Ag) as a marker of endothelial dysfunction has been revealed by Ismail and co-workers.22 In our study, Factor X and VII deficiency in one TOF patient is indicating towards defective formation of Vitamin-K dependent clotting factors, which is likely to be associated with compromised cardiac output and chronic liver congestion as mentioned by Zabala LM et al.17 This evidence concerns the gene VWF and endothelial dysfunction.