[Spatial aspects of blood coagulation dynamics. III. Growth of clots in vitro].

The growth of fibrin clots in thin blood plasma layers was studied. It was found that the clot growth stops or is strongly retarded if its thickness approaches 0.5 mm. Polymer clots growing toward each other fuse together at distances between the coagulation activation centers less than 1 mm, whereas at distances of about 1.5 mm, the clots are separated by ungrowing flat gaps. In some experiments, successive formation of concentric ring-shaped structures was observed. Around the centers of coagulation initiation, up to 3 fibrin rings separated by areas of uncoagulated plasma were formed. The data agree well with the hypothesis advanced by the authors earlier that blood coagulation is regulated by auto-wave mechanism.