Balanescu S, Galinier M, Fourcade J, Dorobantu M, Albenque J P, Massabuau P, Fauvel J M, Bounhoure J P
Service de cardiologie, hôpital universitaire de Bucarest, Roumanie.
Arch Mal Coeur Vaiss. 1996 Aug;89(8):987-90.
To evaluate the correlation between QT interval dispersion (QTd) and ventricular arrhythmias in hypertensive patients (pts) with or without left ventricular hypertrophy (LVH). A secondary aim was to investigate correlations of QTd with other markers of arrythmogenic propensity: ventricular late potentials (LP) and heart rate variability (HRV).
We retrospectively measured the QTd on the 12 standard surface ECG leads in 230 hypertensive pts (94F, 136M; 59.6 +/- 12.7 years old). A 24 hours ECG Holter recording was performed in 218 pts and ventricular arrhythmias were appreciated using the Lown classification. Left ventricular mass was determined by echocardiography (LVM-Devereux formula) and left ventricular mass index (LVMI) were determined in 202 subjects. LP (122 pts) and HRV (55 pts) were investigated.
The QTd varied between 20 and 160 msec (57.8 +/- 32.7 msec). The distribution of pts classified using Lown criteria was: 29 pts (13.3%) class O; 106 pts (48.6%) class I; 8 pts (3.6%) class II; 13 pts (6%) class III; 29 pts (13.3%) class IVa; 33 pts (15.1%) class IVb; 116 pts (69.5%) had LVH determined by echocardiography. The QTd was strongly correlated with the Lown classes (p < 0.0001). The QTd was significantly broader in Lown classes III, IVa and IVb compared to classes O, I and II cumulated (p < 0.002); there was no difference concerning QTd between Lown classes III, IVa and IVb. The QTd was also correlated with the absolute number of premature ventricular depolarizations/24 hours (p = 0.02; r = 0.16). The 75 pts with an increased LVMI had significantly elevated QTd compared to pts without it (p < 0.0001). Qtd was correlated with LVMI (r = 0.37; p < 0.0001). There was no correlation between QTd and the existence of LP (which were correlated with the Lown classes; p < 0.03) and HRV parameters.
Elevated QT interval dispersion is associated with more severe ventricular arrhythmias in hypertensive subjects with LVH. The mechanism of an increased inhomogeneity of repolarisation is probably related to the anatomic modifications induced by LVH. No significant correlation between QTd, LP and HRV was observed.
评估有或无左心室肥厚（LVH）的高血压患者（pts）的QT间期离散度（QTd）与室性心律失常之间的相关性。次要目的是研究QTd与其他心律失常倾向标志物的相关性：心室晚电位（LP）和心率变异性（HRV）。
我们回顾性测量了230例高血压患者（94例女性，136例男性；年龄59.6±12.7岁）12条标准体表心电图导联上的QTd。218例患者进行了24小时动态心电图监测，并使用洛恩分类法评估室性心律失常。通过超声心动图（LVM - 德弗罗公式）测定左心室质量，并在202例受试者中测定左心室质量指数（LVMI）。对122例患者进行了LP研究，对55例患者进行了HRV研究。
QTd在20至160毫秒之间变化（57.8±32.7毫秒）。根据洛恩标准分类的患者分布为：0级29例（13.3%）；Ⅰ级106例（48.6%）；Ⅱ级8例（3.6%）；Ⅲ级13例（6%）；Ⅳa级29例（13.3%）；Ⅳb级33例（15.1%）；经超声心动图测定，116例患者（69.5%）有LVH。QTd与洛恩分级密切相关（p<0.0001）。与累积的0级、Ⅰ级和Ⅱ级相比，Ⅲ级、Ⅳa级和Ⅳb级的QTd明显更宽（p<0.002）；Ⅲ级、Ⅳa级和Ⅳb级之间的QTd没有差异。QTd也与室性早搏/24小时的绝对数量相关（p = 0.02；r = 0.16）。与没有LVMI升高的患者相比，75例LVMI升高的患者QTd显著升高（p<0.0001）。QTd与LVMI相关（r = 0.37；p<0.0001）。QTd与LP的存在（其与洛恩分级相关；p<0.03）和HRV参数之间没有相关性。
在有LVH的高血压患者中，QT间期离散度升高与更严重的室性心律失常相关。复极不均一性增加的机制可能与LVH引起的解剖学改变有关。未观察到QTd、LP和HRV之间有显著相关性。
