Kittnar O, Lechmanová M
Fyziologický ústav 1. LF UK, Praha.
Cesk Fysiol. 2001 Aug;50(3):125-33.
Dispersion of QT intervals has been proposed as a measure of repolarization process inhomogeneity (and thus refractority inhomogeneity) of ventricular myocardium. Recently other possible explanation of this phenomenon has been intensively discussed. According to this concept QT dispersion is explained by different projections of the heart repolarization vector. Moreover, the reproducibility of the measurement of QT dispersion is rather low as it could be influenced both by intrinsic (e.g., amplitude of the T wave or U wave) and extrinsic (e.g. noise, amplitude and time parameters of recording) factors. Only markedly prolonged QT dispersion must be therefore interpreted as a sign of the abnormal course of the repolarization. Nevertheless, according to all mentioned facts the only serious interpretation of increased QT dispersion is that it reflects unspecific repolarization changes. More precious explanation is by then not possible (and it is disputable if it ever will be).
QT间期离散度已被提议作为衡量心室肌复极化过程不均匀性（以及由此产生的不应期不均匀性）的指标。最近，人们对这一现象的其他可能解释进行了深入讨论。根据这一概念，QT离散度是由心脏复极化向量的不同投影来解释的。此外，QT离散度测量的可重复性相当低，因为它可能受到内在因素（如T波或U波的振幅）和外在因素（如噪声、记录的振幅和时间参数）的影响。因此，只有明显延长的QT离散度才能被解释为复极化异常过程的标志。然而，根据上述所有事实，对QT离散度增加的唯一严肃解释是它反映了非特异性的复极化变化。更确切的解释目前还不可能（而且它是否会有更确切的解释也存在争议）。
