Hemodynamic and ECG responses to exercise in children with sickle cell anemia
B. S. Alpert, P. A. Gilman, W. B. Strong, M. F. Ellison, M. D. Miller, J. McFarlane and T. Hayashidera
To determine whether exercise responses are different from normal in
children with sickle cell anemia (SCA), we performed dynamic cycle
ergometer exercise testing in 47 patients with SCA, aged 5 to 18 years, and
170 healthy, black age-matched control subjects. Seven (15%) of the
patients with SCA had definitely ischemic, 16 (34%) had equivocally
ischemic, and 24 (51%) had nonischemic ECG responses. Resting heart rate in
the three groups of patients with SCA was higher than control values.
Maximum exercise heart rate attained was lowest in the definitely ischemic
group. All patients with SCA had decreased blood pressure responses and
maximum working capacity when compared with control subjects. Hemoglobin
concentration was lowest in the definitely ischemic group and correlated
with maximum workload. Long-term myocardial ischemia may lead to fibrosis
and the decreased myocardial contractility seen in adult patients with SCA.
