The effects of sustained handgrip isometric exercise on blood coagulability and platelet function were studied in 10 patients with ischemic heart disease (IHD) and 10 healthy controls. Isometric exercise was performed for 3min at the 50% level of maximal voluntary contraction. Blood sampling was made at rest, and immediately and 6min after exercise.
No significant changes in the platelet sensitivity to ADP-aggregation and β-TG levels were noticed in IHD and control groups after exercise. In IHD fibrinogen levels were higher and antithrombin III activities were lower than those in healthy controls at rest. These two substances increased after exercise in both groups. Prothrombin time and partial thromboplastin time were shortened immediately after exercise in IHD, while these measurements showed no significant changes in healthy controls, The activity of factor VIII increased immediately after exercise in IHD and the activity of factor XII in healthy controls, respectively.
In conclusion, platelet function was not altered in both groups after exercise. However, there was a tendency to an increase in blood coagulability after exercise in IHD. Hemostatic unbalance might be induced after the isometric exercise in IHD patients.