Lubinski A, Lewicka-Nowak E, Kempa M, Baczynska A M, Romanowska I, Swiatecka G
2nd Dept. of Cardiology, Medical University of Gdansk, Poland.
Pacing Clin Electrophysiol. 1998 Jan;21(1 Pt 2):172-5. doi: 10.1111/j.1540-8159.1998.tb01083.x.
There is evidence from experimental studies that the time interval from the peak to the end of T-wave reflects the transmural dispersion in repolarization (electrical gradient) between myocardial "layers" (epicardial, M-cells, endocardial). Since Congenital Long QT Syndrome (LQTS) is considered to be classical disease or repolarisation abnormalities, we performed the present study to assess the transmural dispersion of repolarization in LQTS patients. The study group consisted of 17 patients: 7 LQTS pts and 10 pts from the control group. In each patient the 24-hour ECG recording was performed on magnetic tape. The interval from the peak to the end of the T-wave (TpTo) was automatically measured by Holter system during every hour as a measure of transmural dispersion of repolarisation. Thereafter the mean TpTo from 24-hours was calculated. In addition the spatial QT dispersion was measured from 12 lead ECG and 3 channel Holter tape as a difference between the shortest and the longest QT interval between leads. The values were compared between groups using the Anova test. TpTo was 79.6 +/- 9.6 ms (72-92 ms) in LQTS group and 62.4 +/- 7.5 ms (51-70) in the control group (p < 0.001). In LQTS group TpTo was significantly longer at night hours 72.5 +/- 2 when compared to day hours 87.4 +/- 8 (p < 0.01). The spatial QT dispersion was significantly higher in LQTS patients when compared to control, both in 12-lead standard and Holter ECG. Congenital long QT syndrome is associated with increase in both transmural and spatial dispersion of repolarization. The extent of prolongation of the terminal portion of QT in patients with congenital long QT syndrome is greater at night sleep hours compared to daily activity.
实验研究表明，从T波峰值到结束的时间间隔反映了心肌“层”（心外膜、M细胞、心内膜）之间复极的跨壁离散度（电位梯度）。由于先天性长QT综合征（LQTS）被认为是典型的复极异常疾病，我们进行了本研究以评估LQTS患者的复极跨壁离散度。研究组由17名患者组成：7名LQTS患者和10名对照组患者。对每位患者进行24小时心电图磁带记录。通过动态心电图系统每小时自动测量从T波峰值到结束的时间间隔（TpTo），作为复极跨壁离散度的指标。之后计算24小时的平均TpTo。此外，从12导联心电图和三通道动态心电图磁带测量空间QT离散度，即导联间最短和最长QT间期的差值。使用方差分析对两组间的值进行比较。LQTS组的TpTo为79.6±9.6毫秒（72 - 92毫秒），对照组为62.4±7.5毫秒（51 - 70毫秒）（p < 0.001）。在LQTS组中，夜间TpTo为72.5±2毫秒，显著长于白天的87.4±8毫秒（p < 0.01）。与对照组相比，LQTS患者的空间QT离散度在12导联标准心电图和动态心电图中均显著更高。先天性长QT综合征与复极的跨壁和空间离散度增加有关。与日常活动相比，先天性长QT综合征患者夜间睡眠时QT终末部分的延长程度更大。
