Andersen Mads P, Xue Joel Q, Graff Claus, Kanters Jørgen K, Toft Egon, Struijk Johannes J
Department of Health Science and Technology, Aalborg University, Aalborg, Denmark.
J Electrocardiol. 2008 Nov-Dec;41(6):557-61. doi: 10.1016/j.jelectrocard.2008.07.021. Epub 2008 Sep 19.
T-wave morphology descriptors are sensitive to drug-induced changes and may be a useful addition to the QT interval in cardiac safety trials. Intrasubject heart rate dependence of T-wave morphology was investigated in a sample of 39 healthy individuals. Ten-second electrocardiograms were obtained from daytime Holter recordings. Duration parameters (QT, ToTe, TpTe, and others), a number of basic T-wave morphology parameters (amplitude, area, and others) as well as advanced morphology descriptors (asymmetry, flatness, and others) were measured automatically. Heart rate dependence was examined by means of analysis of covariance. The results showed clear heart rate dependence for the QT interval (R(2) = 0.53-0.57) and a moderate degree of heart rate dependence for the basic morphology parameters (amplitude, area, and others) (R(2) = 0.17-0.42). Both the advanced T-wave descriptors (asymmetry, flatness, and others), ToTe intervals and TpTe intervals, were practically independent of heart rate (R(2) = 0-0.08), making heart rate correction unnecessary for these parameters.
T波形态描述符对药物引起的变化很敏感，在心脏安全性试验中可能是对QT间期的有益补充。在39名健康个体的样本中研究了T波形态的个体内心率依赖性。从白天的动态心电图记录中获取10秒的心电图。自动测量持续时间参数（QT、ToTe、TpTe等）、一些基本的T波形态参数（振幅、面积等）以及高级形态描述符（不对称性、平坦度等）。通过协方差分析来检查心率依赖性。结果显示QT间期有明显的心率依赖性（R² = 0.53 - 0.57），基本形态参数（振幅、面积等）有中等程度的心率依赖性（R² = 0.17 - 0.42）。高级T波描述符（不对称性、平坦度等）、ToTe间期和TpTe间期实际上都与心率无关（R² = 0 - 0.08），因此这些参数无需进行心率校正。
