Zaidi M, Robert A, Fesler R, Derwael C, Brohet C
Division of Cardiology, Cliniques Universitaires Saint Luc, Brussels, Belgium.
Heart. 1997 Oct;78(4):371-5. doi: 10.1136/hrt.78.4.371.
To examine whether, in coronary patients after myocardial infarction, the dispersion of ventricular repolarisation measured through QT and JT intervals from a surface electrocardiogram could allow separation of those with ventricular tachyarrhythmias (VT) complicating their myocardial infarct from those without.
A retrospective comparative study.
University hospital.
39 patients with myocardial infarction complicated by VT, 300 patients after myocardial infarction without arrhythmic events, and 1000 normal subjects. The myocardial infarction groups were divided into anterior, inferior, and mixed locations.
A computer algorithm examined an averaged cycle from a 10 second record of 15 simultaneous leads (12 lead ECG + Frank XYZ leads). After interactive editing, four intervals were computed: QTapex, JTapex, QTend, and JTend. For each interval, the dispersion was defined as the difference between the maximum and minimum values across the 15 leads.
The mean values of all four dispersion indices were higher in patients with myocardial infarction than in normal subjects (p < 0.01). In the infarct groups, patients with VT had significantly greater mean and centile dispersion values than those without VT. For instance, the 97.5th centile value of QTend was 65 ms in normal individuals, 90 ms in infarct patients without arrhythmia, and 128 ms in those with VT; 70% of the infarct patients who developed serious ventricular arrhythmias had values exceeding the 97.5th centile of the normal group, while only 18% of the infarct patients without arrhythmia had dispersion values above this normal upper limit. Among the infarct patients, nearly half of those (18 of 39) with tachyarrhythmias had dispersion values that exceeded the 97.5th centile of those without arrhythmia.
Dispersion of ventricular repolarisation may be a good non-invasive tool for discriminating coronary patients susceptible to VT from those who are at low risk.
研究心肌梗死后的冠心病患者中，通过体表心电图的QT和JT间期测量的心室复极离散度是否能够区分并发心室性心律失常（VT）的心肌梗死患者和未并发者。
回顾性比较研究。
大学医院。
39例并发VT的心肌梗死患者、300例心肌梗死后无心律失常事件的患者以及1000名正常受试者。心肌梗死组又分为前壁、下壁和混合部位梗死。
一种计算机算法分析了15个同步导联（12导联心电图 + Frank XYZ导联）10秒记录中的平均心动周期。经过交互式编辑后，计算出四个间期：QTapex、JTapex、QTend和JTend。对于每个间期，离散度定义为15个导联中的最大值与最小值之差。
心肌梗死患者的所有四个离散度指标的平均值均高于正常受试者（p < 0.01）。在梗死组中，并发VT的患者的平均离散度值和百分位数离散度值显著高于未并发VT的患者。例如，QTend的第97.5百分位数在正常个体中为65毫秒，在无心律失常的梗死患者中为90毫秒，在并发VT的患者中为128毫秒；发生严重室性心律失常的梗死患者中有70%的值超过正常组的第97.5百分位数，而无心律失常的梗死患者中只有18%的离散度值高于该正常上限。在梗死患者中，近一半（39例中的18例）发生快速心律失常的患者的离散度值超过了无心律失常患者的第97.5百分位数。
心室复极离散度可能是一种很好的非侵入性工具，用于区分易发生VT的冠心病患者和低风险患者。
