Doi Y, Takada K, Mihara H, Kawano T, Nakagaki O, Ogawa S, Arakawa K
Department of Internal Medicine, Saiseikai Fukuoka General Hospital, Japan.
Jpn Heart J. 1995 Sep;36(5):573-81. doi: 10.1536/ihj.36.573.
QT and QT dispersion, which is the time difference between QT maximum and QT minimum, were evaluated in 22 patients with anterior myocardial infarction approximately one month after onset. The purpose of this study was to observe how LV wall motion abnormally is related to these variables. Twenty age-matched patients without overt heart disease were also studied as a control group. QT and QT max in patients with acute myocardial infarction (AMI) were markedly prolonged compared to those in normal controls (472.8 +/- 48.0, 483.2 +/- 32.1 vs 390.2 +/- 18.8, and 418.0 +/- 21.0 msec, respectively). QT dispersion and QTc dispersion in patients with AMI were significantly more prolonged than in normal controls (111.2 +/- 33.9, (113.4 +/- 32.9 vs 54.3 +/- 15.0, and 60.3 +/- 17.2 msec, respectively). QT dispersion has a positive correlation with QT max in AMI patients. Ejection fraction (EF) of the left ventricle was relatively well maintained in cases where only one segment of the left anterior ventricular wall was impaired in its motion. It decreased, however, in accordance with the extent of wall motion abnormality QT max and QTc max were prolonged as the number of LV wall segments with impairment increased. This, however, was not statistically significant. QT dispersion and QTc dispersion had no relation to the extent of LV wall motion abnormality nor to EF of the left ventricle In conclusion, no definite relationships between QT dispersion (QTc dispersion) and EF of the left ventricle, or between these variables and the extent of left ventricular wall motion abnormality were found in patients with anterior myocardial infarction in our study. Although both QT max and QT dispersion were prolonged in patients with myocardial infarction, this suggests that electrical heterogeneity or regional variation in electrical ventricular recovery did not always parallel the severity of mechanical abnormality of the left ventricle.
对22例急性前壁心肌梗死患者在发病约1个月后评估了QT间期和QT离散度（QT离散度为QT最大值与QT最小值之间的时间差）。本研究的目的是观察左心室壁运动异常与这些变量之间的关系。另外选取20例年龄匹配且无明显心脏病的患者作为对照组进行研究。与正常对照组相比，急性心肌梗死（AMI）患者的QT间期和QT最大值明显延长（分别为472.8±48.0、483.2±32.1毫秒与390.2±18.8、418.0±21.0毫秒）。AMI患者的QT离散度和校正QT离散度明显比正常对照组延长（分别为111.2±33.9、113.4±32.9毫秒与54.3±15.0、60.3±17.2毫秒）。AMI患者中QT离散度与QT最大值呈正相关。在左前室壁仅一个节段运动受损的病例中，左心室射血分数（EF）相对保持良好。然而，随着室壁运动异常范围的增加，EF降低。随着左心室壁节段受损数量的增加，QT最大值和校正QT最大值延长。然而，这在统计学上无显著意义。QT离散度和校正QT离散度与左心室壁运动异常范围及左心室EF均无关。总之，在我们的研究中，急性前壁心肌梗死患者中未发现QT离散度（校正QT离散度）与左心室EF之间，或这些变量与左心室壁运动异常范围之间存在明确关系。虽然心肌梗死患者的QT最大值和QT离散度均延长，但这表明电不均一性或心室电恢复的区域差异并不总是与左心室机械异常的严重程度平行。
