Background: In hematopoietic stem cell transplantation (SCT) of leukemia, the heart failure is one of the serious complications, but has difficulty with a prediction. QT dispersion (QTD) has been studied as a predictive factor of heart failure and fatal arrhythmia in adults. The purpose of this study is to examine whether QTD predicts cardiac events, such as heart failure and arrhythmia, after SCT in children.
Methods: Fourteen patients (mean age: 6.6 years; 6 men; 8 acute lymphoblastic leukemia, 6 acute myeloblastic leukemia) who received SCT were studied retrospectively. Twelve lead electrocardiograms and echocardiography were performed for all patients before conditioning therapy. QTD, corrected QT dispersion (QTcD), echocardiographic functional parameters and cumulative anthracycrine dose (ADR) were evaluated. Patients were divided into two groups, patients with cardiac event group (CE+) and without cardiac event group (CE-) after SCT. We compared these values between 2 groups.
Results: All patients were treated with cyclophosphamide and performed total body irradiation in the conditioning therapy. Six patients experienced cardiac events (arrhythmia in 2, heart failure in 4). There were significant differences as QTD (CE+ vs. CE-; 48.3 vs. 27.8 ms,p=0.003), QTcD (60.7 vs. 37.5 ms,p=0.003) and ADR (297.6 vs. 166.8 mg/m2,p=0.002). Echocardiographic parameters did not show significant difference between 2 groups.
Conclusion: QTD could be used as a noninvasive predictor of cardiac events after SCT in children. Despite the absence of echocardiographic abnormalities, patients with a very high QTD were needed care of cardiac events associated with SCT.