Moderate-intensity exercise improves the thromboelastography coagulation index in children with severe hemophilia A

This pilot study explored the effect of moderate-intensity exercise on factor VIII (FVIII) activity and global hemostatic status of the children with severe hemophilia A. Eleven children aged 6 to 15 years with severe hemophilia A participated in a moderate-intensity exercise test by using Recumbent Cross Trainer (NuStep, T5XR) for at least 10 min after reaching the target heart rate or until volitional exhaustion within a safety framework. Blood samples were collected pre and postexercise for plasma FVIII: C and thromboelastography (TEG) parameters and coagulation index. The average duration of exercise was 11.8 min (10-13 min). There was no report on bleeding events or adverse symptoms requiring termination of the exercise test. The average FVIII activity of the 11 children was 0.66 (0.5-0.8) IU/dl before and 0.93 (0.5-2.3) IU/dl after exercise. The increase of FVIII in the 11 children as a group was not statistically significant (P = 0.052). There were significant changes of TEG measurements, with shortening of R (P < 0.05), and increase in K decrease (P < 0.05), alpha angle (P < 0.05), maximum amplitude (P < 0.05), and coagulation index (P < 0.01). Among the 11 children, the relative coagulation index increase after exercise was greater than 50% in seven (63.6%), less than 20% in three (27.3%), and less than 10% in one (9.1%). TEG analysis showed that the global hemostatic function for the children with severe hemophilia A can be enhanced after moderate-intensity exercise.

Thromboelastography reflects global hemostatic variation among severe haemophilia A dogs at rest and following acute exercise

The heterogeneity among severe haemophilia A patients reflects on variable tendencies for bleeding and also variable responses to FVIII therapy. This variability cannot be detected or predicted by routine coagulation tests. Thromboelastography (TEG) has recently been evaluated for assessing hemostatic patterns in haemophiliacs and proved valuable in monitoring therapy and/or prophylaxis, however, usually only in limited small case series. Exercise is an important component of overall haemophilia care, however, in severe haemophiliacs there is an increased risk of bleeding. The availability of a validated hemostatic test to evaluate the influence of exercise would be advantageous. This study has used TEG analysis to evaluate the global hemostatic status of a group of severe haemophilia A dogs at rest and after a standardized period of exercise. The study demonstrated significant inter and intra-individual variations based on TEG patterns at rest and following acute exercise as well as significant improvement of global hemostasis after exercise in the majority of tested dogs. The study supports the utilization of TEG in assessment of the hemostatic pattern in severe haemophilia A and provides a potential for utilizing TEG evaluation in managing exercise regimens for haemophilia care.