Background: We studied serum N-terminal atrial natriuretic peptide (NT-ANP) in children during and after chemotherapy for cancer to determine its applicability in detecting cardiac dysfunction. Forty-three patients were receiving chemotherapy for malignancy. Forty-eight patients were off chemotherapy and survived between 0.9 and 13 (median 5) years after the diagnosis, receiving cumulative anthracycline doses between 0 and 600 (median 225) mg/m2.
Procedure and results: Cardiac evaluation of the patients included measurement of serum NT-ANP, recording of ECG, and assessment of systolic and diastolic function of the heart by echocardiography. During chemotherapy, serum NT-ANP levels were higher than in controls but varied markedly in the same individuals. Serum NT-ANP levels showed no consistent increase in the weeks following anthracycline administration. In late follow-up, serum NT-ANP levels were higher than in age-matched controls (median (range), 0.22 (0.06-0.47) vs. 0.14 (0.06-0.27) nmol/l, respectively, P < .001). The subgroup of patients with bone marrow transplantation and/or cardiac irradiation had the highest NT-ANP concentrations (0.30 (0.20-0.45) nmol/l).
Conclusions: Thus, serum NT-ANP measurements seemed to represent a useful contribution in the long-term cardiac follow-up of children after cancer. This blood test can readily be included to laboratory follow-up, is reasonably inexpensive and may decrease the need for more laborious tests of cardiac function. When there is ongoing chemotherapy, NT-ANP levels are influenced by a variety of factors that invalidate its routine use during this period.