Gupta Monesha, Thaler Howard T, Friedman Deborah, Steinherz Laurel
Division of Pediatric Cardiology, Memorial Sloan-Kettering Cancer Center, New York, New York, USA.
Pediatr Hematol Oncol. 2002 Dec;19(8):533-42. doi: 10.1080/08880010290097387.
To determine the incidence of abnormal dispersion of QT intervals on an ECG the authors measured these intervals in long-term survivors after anthracycline treatment for childhood malignancies and compared the incidence to the traditional markers, prolonged QT and QTc intervals. Prolonged QT dispersion (QTd) and corrected QT dispersion (QTcd) have been associated with serious arrhythmias and sudden death in many forms of heart disease. The above intervals and shortening fraction (SF) on echocardiogram were determined in 64 late survivors who were 4-22 years post anthracycline therapy. They were divided into 2 groups: group I, 39 patients with normal function with SF >or= 29%, and group II, 15 patients with SF < 29%. An additional 10 patients had died and had SF < 29% at the time of death. They were divided into 2 groups: group III, 5 patients who died with heart failure after a mean of 12 years from of therapy, and group IV, 5 patients who had a sudden cardiac death after a mean of 9 years from end of therapy. In group I patients, the incidence of prolonged QT and QTc intervals was < 6%, whereas that of QTd and QTcd was > 38%. In group II patients, the presence of prolonged QT and QTc intervals was < 16%, whereas that of QTd and QTcd was > 40%. The QTc (p =.01), QTd (p =.02), and QTcd (p =.01) were significantly higher and SF (<.01) significantly lower in group IV compared to those alive (group I and II patients) with no significant difference in age, number of years of follow-up, precordial radiation dose, or anthracycline dose between the two. The combination of QTcd > 110 ms and diminished SF < 29% was found to be associated with sudden death. In summary, the long-term survivors of anthracycline therapy had a high incidence (>38%) of abnormally prolonged QT dispersion intervals, QTd and QTcd, even in those with normal QT and QTc on an ECG and normal shortening fraction on an echocardiogram.
为了确定心电图上QT间期异常离散的发生率，作者对接受蒽环类药物治疗儿童恶性肿瘤的长期存活者进行了这些间期的测量，并将其发生率与传统指标——QT和QTc间期延长进行比较。QT间期离散度延长（QTd）和校正QT间期离散度（QTcd）在多种形式的心脏病中与严重心律失常和猝死相关。对64例蒽环类药物治疗后4至22年的晚期存活者测定了上述间期以及超声心动图上的缩短分数（SF）。他们被分为两组：第一组，39例心功能正常且SF≥29%的患者；第二组，15例SF＜29%的患者。另有10例患者已死亡，死亡时SF＜29%。他们被分为两组：第三组，5例平均在治疗后12年死于心力衰竭的患者；第四组，5例平均在治疗结束后9年发生心源性猝死的患者。在第一组患者中，QT和QTc间期延长的发生率＜6%，而QTd和QTcd的发生率＞38%。在第二组患者中，QT和QTc间期延长的发生率＜16%，而QTd和QTcd的发生率＞40%。与存活者（第一组和第二组患者）相比，第四组患者的QTc（p = 0.01）、QTd（p = 0.02）和QTcd（p = 0.01）显著更高，而SF（p＜0.01）显著更低，两组在年龄、随访年限、胸前区放射剂量或蒽环类药物剂量方面无显著差异。发现QTcd＞110 ms且SF降低＜29%的组合与猝死相关。总之，蒽环类药物治疗的长期存活者即使心电图上QT和QTc正常且超声心动图上缩短分数正常，其QT离散间期异常延长（QTd和QTcd）的发生率也很高（＞38%）。
