Wang Lexin
School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, Australia.
Exp Clin Cardiol. 2003 Spring;8(1):31-2.
Congenital long QT syndrome (LQTS) is a group of ion channel disorders of ventricular myocytes caused by mutations of genes that encode these ion channels. The main clinical features of LQTS are syncope, cardiac arrest and QT prolongation on body surface electrocardiogram. The present study reports on the case of a 42-year-old female patient with a 10-year history of LQTS and syncopal attacks resistant to beta-blocker therapy. Treadmill exercise testing in this patient increased the corrected QT interval (QTc) from 0.48 s to 0.54 s and reduced the amplitude of the T wave. Left cardiac sympathectomy did not affect the resting heart rate or QTc but it prevented exercise-induced T wave reduction and QTc prolongation. Therefore, sympathetic activation plays a key role in exerciseinduced QT prolongation and changes in T wave morphology in patients with congenital LQTS.
先天性长QT综合征（LQTS）是一组由编码离子通道的基因突变引起的心室肌细胞离子通道疾病。LQTS的主要临床特征是晕厥、心脏骤停以及体表心电图QT间期延长。本研究报告了一名42岁女性患者的病例，该患者有10年长QT综合征病史且对β受体阻滞剂治疗耐药，有晕厥发作。该患者的平板运动试验使校正QT间期（QTc）从0.48秒增加到0.54秒，并降低了T波振幅。左侧心脏交感神经切除术未影响静息心率或QTc，但可防止运动诱发的T波降低和QTc延长。因此，交感神经激活在先天性LQTS患者运动诱发的QT延长和T波形态改变中起关键作用。
