Kulan K, Ural D, Komsuoğlu B, Ağaçdiken A, Göldeli O, Komsuoğlu S S
Department of Cardiology, Black Sea Technical University, Medical Faculty, Trabzon, Turkey.
Int J Cardiol. 1998 Apr 1;64(2):179-84. doi: 10.1016/s0167-5273(98)00017-5.
The present study was designed to detect the arrhythmogenic effect of left ventricular hypertrophy, QTc prolongation and the relationship between the QTc duration and ventricular arrhythmias in patients with left ventricular hypertrophy secondary to essential hypertension. Sixty-eight hypertensive patients (51 male and 17 female, mean age 52+/-6 years) and 30 healthy normotensive subjects (22 male and eight female, mean age 49+/-6 years) were enrolled in the study. The frequency of ventricular arrhythmias was investigated with 24-h ambulatory electrocardiographic monitoring and grade 3 and 4 ventricular arrhythmias according to a modified Lown and Wolf classification were accepted as complex arrhythmias. The echocardiographic features of the patients were divided into five groups as follows: (1) normal left ventricular diameter and wall thickness, (2) concentric left ventricular hypertrophy, (3) asymmetric septal hypertrophy, (4) dilated left ventricle, (5) dilated and hypertrophic left ventricle. The frequency of complex ventricular ectopia and the QTc duration were estimated for each group and compared with Student's t-test. Left ventricular hypertrophy was detected in 38 of 68 patients (56%) with essential hypertension. In patients with left ventricular hypertrophy, the incidence of complex ventricular arrhythmias was two- and fivefold higher compared with patients without left ventricular hypertrophy and with controls, respectively. All of the patients with echocardiographic left ventricular dilatation had experienced complex ventricular arrhythmias. QTc duration correlated positively with left ventricular mass index and left ventricular internal diastolic dimension. The highest QTc intervals were detected in patients with left ventricular hypertrophy and complex arrhythmias. In patients with left ventricular hypertrophy, a QTc duration longer than 380 ms had a sensitivity of 74% and a specificity of 89% for detecting complex ventricular arrhythmias. It is concluded that patients with left ventricular hypertrophy have a higher incidence of complex ventricular arrhythmias and QTc prolongation in those patients can be a good marker for the increased risk of arrhythmias.
本研究旨在检测原发性高血压继发左心室肥厚患者的致心律失常作用、QTc延长情况以及QTc间期与室性心律失常之间的关系。68例高血压患者（51例男性，17例女性，平均年龄52±6岁）和30例健康血压正常者（22例男性，8例女性，平均年龄49±6岁）纳入本研究。采用24小时动态心电图监测调查室性心律失常的发生频率，根据改良的洛恩和沃尔夫分类法，3级和4级室性心律失常被视为复杂性心律失常。患者的超声心动图特征分为以下五组：（1）左心室直径和壁厚正常；（2）向心性左心室肥厚；（3）不对称性室间隔肥厚；（4）左心室扩张；（5）左心室扩张并肥厚。对每组的复杂性室性早搏发生频率和QTc间期进行评估，并采用学生t检验进行比较。68例原发性高血压患者中有38例（56%）检测到左心室肥厚。在左心室肥厚患者中，复杂性室性心律失常的发生率分别比无左心室肥厚患者和对照组高2倍和5倍。所有超声心动图显示左心室扩张的患者均有复杂性室性心律失常。QTc间期与左心室质量指数和左心室内径舒张末期呈正相关。左心室肥厚合并复杂性心律失常患者的QTc间期最长。在左心室肥厚患者中，QTc间期大于380 ms对检测复杂性室性心律失常的敏感性为74%，特异性为89%。结论是，左心室肥厚患者复杂性室性心律失常的发生率较高，这些患者的QTc延长可能是心律失常风险增加的一个良好标志物。
