In order to detect early-stage left ventricular dysfunction, we examined a load-independent index, that is, the stress-velocity relation, by echocardiography in 13 patients with aplastic anemia including pure red cell anemia. Even when left ventricular contractility and pump function were within the normal range, its afterload had a tendency to increase in transfusion-dependent patients. The patients who had impairment of cardiac pump function died of congestive heart failure within one year after abnormal findings in stress-velocity relation were detected. Therefore, the stress-velocity relation is a sensitive, useful and noninvasive index for detecting asymptomatic myocardial dysfunction in patients with transfusion-dependency and chronic iron overload. It is necessary for these patients to undergo examinations of echocardiography at regular intervals. In case of abnormally in the stress-velocity relation, treatment for afterload mismatch and more effective chelation should be recommended to reduce the burden on the heart. Thereby, the heart is kept in better condition and the prognosis of these patients will be improved.
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