Wang Chia-Liang, Lee Wen-Lieng, Wu Ming-Ju, Cheng Chi-Hung, Chen Cheng-Hsu, Shu Kuo-Hsiung
Department of Medicine, Division of Nephrology, Taichung Veterans General Hospital, Taichung, Taiwan.
Am J Kidney Dis. 2002 Mar;39(3):539-48. doi: 10.1053/ajkd.2002.31418.
QT dispersion (the difference between maximum and minimum QT across the 12-lead electrocardiogram [ECG]), which reflects regional variations in ventricular repolarization, is a predictor of arrhythmia and cardiovascular mortality. The present study was undertaken to assess the difference in QT dispersion between uremic and nonuremic patients with acute myocardial infarction (AMI) and its relationship to post-AMI clinical outcome. Twelve-lead ECG recordings were obtained the first and third days after the onset of AMI in 21 uremic and 21 nonuremic patients. QT intervals were measured on 12-lead ECGs and corrected by heart rate (QTc). Our findings show that uremic patients with AMI had greater QTc dispersion (84 +/- 35 versus 55 +/- 15 milliseconds; P < 0.001), a greater 1-year mortality rate (48% versus 18%; P = 0.003), and underwent fewer reperfusion therapies (5 of 21 versus 17 of 21 patients; P = 0.002) compared with nonuremic patients with AMI. Patients with AMI who died had greater QTc dispersion than those who survived (102 +/- 40 versus 67 +/- 40 milliseconds; P = 0.015). An optimal QTc dispersion cutoff value of 60 milliseconds had a sensitivity of 100% and specificity of 55% in predicting 1-year mortality in uremic patients with AMI. Uremic patients with AMI administered thrombolytic therapies (n = 5) had reduced 1-year mortality rates (0% versus 63%; P = 0.003) and shortened QTc dispersion from days 1 to 3 (changes in QTc dispersion between days 1 and 3, 29% +/- 9% decrease versus 13% +/- 5% increase; P = 0.001) compared with those without therapies (n = 16). Our findings suggest that greater QT dispersion is associated with greater total mortality, and thrombolytic therapies could reduce QTc dispersion and mortality in uremic patients with AMI. It is prudent to refine our current management regimen for uremic patients with AMI to improve the poor clinical outcome.
QT离散度（12导联心电图[ECG]上最大QT与最小QT之间的差值）反映心室复极的区域差异，是心律失常和心血管死亡率的预测指标。本研究旨在评估急性心肌梗死（AMI）的尿毒症患者和非尿毒症患者之间QT离散度的差异及其与AMI后临床结局的关系。在21例尿毒症患者和21例非尿毒症患者AMI发作后的第一天和第三天记录12导联心电图。在12导联心电图上测量QT间期并根据心率进行校正（QTc）。我们的研究结果表明，与非尿毒症AMI患者相比，尿毒症AMI患者的QTc离散度更大（84±35毫秒对55±15毫秒；P<0.001），1年死亡率更高（48%对18%；P=0.003），接受再灌注治疗的次数更少（21例患者中有5例对21例患者中有17例；P=0.002）。死亡的AMI患者的QTc离散度高于存活患者（102±40毫秒对67±40毫秒；P=0.015）。在预测尿毒症AMI患者的1年死亡率方面，60毫秒的最佳QTc离散度临界值的敏感性为100%，特异性为55%。接受溶栓治疗的尿毒症AMI患者（n=5）的1年死亡率降低（0%对63%；P=0.003），并且从第1天到第3天QTc离散度缩短（第1天和第3天之间QTc离散度的变化，下降29%±9%对上升-13%±5%；P=0.001），与未接受治疗的患者（n=16）相比。我们的研究结果表明，更大的QT离散度与更高的总死亡率相关，溶栓治疗可以降低尿毒症AMI患者的QTc离散度和死亡率。谨慎地优化我们目前对尿毒症AMI患者的管理方案以改善不良的临床结局是明智的。
