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

Abstract

The 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 from an exercised normal person. The shortening effect on bleeding time seemed also to remain in the patient on the nearest following days. The transfusion gave a definitely more marked correction of the bleeding time than a previous transfusion to the same patient with ordinary plasma from four times the amount of blood.

Further, transfusion experiments showed that the principle inducing the shortening of bleeding time, resides in the plasma and not in the platelets.

The effect of exercise-activated blood on hemostasis was controlled on a patient in connection with tooth extraction.

The results indicate a physiological interrelationship between the two seemingly different defects in von Willebrand's disease.

Investigations on two patients from the two last families (group II), with AHA levels about 2–7 per cent, showed:

Transfusions with exercise-activated blood or plasma shortened their prolonged plasma cephalin time and increased the AHA activity, but no correcting effect could be observed on their prolonged bleeding times.

The study lends support to a hypothesis that the two groups of patients represent different types of von Willebrand's disease.