The Effect of Muscular Exercise on Hemostasis in Von Willebrand's Disease

AbstractThe effect of muscular exercise on hemostasis was studied in eight patients with von Willebrand's disease.The patients belonged to four different families. Two of the families presented the typical pattern of a simple dominant auto-somal inheritance. In the two others the mode of inheritance was more uncertain. Family histories indicated here an autosomal recessive inheritance of the severe defect, with heterozygotes having only a slight or no bleeding tendency.Investigations on patients from the first two families (group I), having antihemophilic A factor (AHA = f. VIII) levels in the range 20–50 per cent of normal, showed: Strenuous muscular exercise for three minutes was followed by decrease in plasma cephalin time and increase in AHA, similarly to that established for normal persons. The bleeding time decreased, though not to normal range.A restoration of a patient's bleeding time to normal, simultaneously with an increase in AHA level, was attained by transfusion with only 500 ml ACD blood fr...