Effect of epirubicin-based chemotherapy and dexrazoxane supplementation on QT dispersion in non-Hodgkin lymphoma patients

Background and objective. – Aim of the present study was to assess the effect of epirubicin-based chemotherapy on QT interval dispersion in patients with aggressive non-Hodgkin lymphoma (NHL), and the effect of dexrazoxane supplementation. Prolongation of QT dispersion may not only represent a sensitive tool in identifying the first sign of anthracycline-induced cardiotoxicity, but it may serve also in identifying patients who are at risk of arrhythmic events. Methods. – Twenty untreated patients, ≤60 years of age with newly-diagnosed aggressive NHL, eligible for a treatment with epirubicin-based chemotherapy were selected for the study. The patients were randomly allocated in two subgroups (N = 10) to receive or not dexrazoxane hydrochloride (400 mg/m2) after epirubicin infusion. The patients underwent 12-lead electrocardiogram (ECG) before and after epirubicin infusion and after dexrazoxane supplementation. QT dispersion was defined as the difference between the maximum and the minimum QT interval occurring in any of the 12 ECG leads, corrected (QTc) for heart rate. Results. – All the 20 patients showed increased QT dispersion (44.3 ± 8.4 vs. 68.4 ± 11.4 ms, P < 0.001) and QTc dispersion (46.2 ± 6.2 vs. 72.2 ± 8.4, P < 0.001) after chemotherapy infusion. The 10 patients who underwent supplementation with dexrazoxane exhibited a significant reduction of QT dispersion (67.4 ± 8.1 vs. 49.5 ± 4.2 ms, P < 0.001) and QTc dispersion (71.2 ± .7 vs. 51.4 ± 4.3 ms, P < 0.001), while the 10 patients not supplemented with dexrazoxane did not (QT dispersion: 69.3 ± 7.6 vs. 64.2 ± 6.9 ms; QTc dispersion: 72.8 ± 8.1 vs. 67.3 ± 7.2 ms, ns). Conclusions. – Epirubicin-based chemotherapy causes an early increase of the QT and QTc dispersion, which is attenuated by dexrazoxane supplementation. Therefore, dexrazoxane can reduce the arrhythmic risk in patients treated with epirubicin.