抄録
Plasma levels of vitamin K, which is composed of phylloquinone and menaquinone and protein C antigen were measured in thirty patients on long-term warfarin therapy after cardiac surgery. Thirty patients were devided in two groups by means of the type of cardiac surgery. Twenty patients of group A were the cases of cardiac valve replacement and ten patients of group B were the cases of coronary artery bypass grafting. Group A was divided further in two grops, group A-(1) and group A-(2) according to the amount of warfarin doses. Vitamin K was measured by high-performance liquid chromatography and protein C antigen was measured by ELISA method.
Thrombotest values of groups A and B ranged on an average of 20.2±3.9% and 20.7±5.3%. Plasma levels of vitamin K and protein C antigen in both groups were on an average of 1.36±0.44ng/ml versus 2.64±1.56ng/ml (p<0.05) and 93.4±20.22% versus 107.2±13.94% respectively. There was no difference between group A-(1) and A-(2).
There was no case in which vitamin K and protein C decreased below the normal levels. These findings suggest that long-term warfarin therapy has no influence on the synthesis of vitamin K and protein C in patients after cardiac surgery.
