Abstract：Objective To investigate the changes of QT dispersion and ECG in 40 cases of patients with nasopharyngeal carcinoma after radiotherapy. MethodsThe forty patients were enrolled in the radiotherapy of 3 phases with gradually increased radiological dose of 15-25 Gy, 35-45 Gy and 55-65 Gy. Meanwhile, 24-hour ambulatory electrocardiography(AECG) monitoring was carried out in each phase of radiotherapy. The changes of QT dispersion(QTd), corrected QT dispersion(QTcd) and ECG changes induced by the radiotherapy were observed.ResultsThis paper made a comparison among the patients before radiotherapy and after 3 phases of radiotherapy, and the results were as follows. ① In AECG, the differences of indexes of QTd and QTcd weren’t statistically significant(P＞0.05); ② There was also no statistical significance(P＞0.05) in the differences of the incidence rates of supraventricular arrhythmia, ventricular arrhythmia and ST-T changes. ConclusionThe indexes of QTd and QTcd decreased at a radiological dose of 15-25 Gy, increased at a dose of 35-45 Gy and returned to pretreatment levels at a dose of 55-65 Gy. The trends of the incidence rates of ventricular arrhythmia and ST-T changes were similar, which performed as an increased trend at a radiological dose of 15-25 Gy, a decreased trend at a dose of 35-45 Gy and a significant increased trend again at a dose of 55-65 Gy. It deserves further observation and investigation.
2014, Vol. 23 
