DOBUTAMINE STRESS ECHOCARDIOGRAPHY IN THE EVALUATION OF LATE ANTHRACYCLINE CARDIOTOXICITY IN CHILDHOOD-CANCER SURVIVORS

Late anthracycline cardiotoxicity has been of increasing concern to pe diatric oncologists. An increasing number of patients with cardiac dys function has been reported without a good correlation between cardiac function or symptoms and routine echocardiographic follow-up. We studi ed dobutamine stress echocardiography in patients who had received mod erate doses of anthracyclines years before. Twenty-three patients (14 male, 9 female; 7-25 y) who completed chemotherapy with moderate doses of anthracyclines (180-380 mg/m(2)) more than 2 y previously underwen t dobutamine stress echocardiography and were compared with a control group of 26 healthy young people (15 male, 11 female; 6-26 y) matched for age and weight. Dobutamine was administered in three periods up to a rate of 5 mu g/kg/min. Eighty-five percent of the patients showed a n abnormal response to dobutamine. Both systolic and diastolic functio ns were Effected. The systolic dysfunction was not related to diminish ed contractility but to an elevated systolic wall stress due to inadeq uate cardiac muscle thickening. The diminished wall thickening was rel ated to the length of follow-up. Dobutamine proved to be a very sensit ive method to detect clinical and subclinical cardiac dysfunction in p atients post anthracycline chemotherapy and questions the concept of a safe dose.