Detection of early anthracycline-induced cardiotoxicity in childhood cancer with dobutamine stress echocardiography

Asymptomatic long-term survivors of childhood cancer treated with anthracyclines may have latent cardiac dysfunction which is undetected by commonly used echocardiographic methods. A more sensitive echocardiographic screening test, dobutamine stress echocardiography, was performed on 22 patients (mean age 9.10 +/- 3.79 years) treated with 75 to 450 mg/m(2) of anthracyclines (mean 210.45 +/- 127.34) and results were compared with 22 healthy age-matched control subjects. Echocardiographic Doppler studies were performed after each dobutamine infusion of 0.5, 2.5, 5 and 10 mu g/kg/min. Although left ventricular mass was decreased and end-systolic wall stress increased in the patilent group when compared with the control subjects (p < 0.01 and p < 0.05, respectively), no differences were found between shortening fraction and ejection force in control subjects and patients, at rest and during each dobutamine infusion. A decreased mitral E/A ratio (ratio of early-to-late peak tilling velocity) was demonstrated in anthracycline-treated patients only during dobutamine infusion (p < 0.01). Our data showed left ventricular diastolic dysfunction during inotropic stimulation with dobutamine, and suggest that dobutamine stress echocardiography is a useful technique for evaluating the cardiac status of anthracycline-treated patients on a long-term basis.