继发性长 QT 综合征与尖端扭转型室性心动过速

长 QT 综合征（long-QT syndrome，LQTS）为心室复极时程延长、不均一性及离散度增大的一种疾病，其危险性在于尖端扭转型室性心动过速（torsade de pointes，TdP）、心室颤动的发生，临床表现为晕厥、搐搦或猝死。LQTS 包括遗传性长 QT 综合征（cLQTS）和继发性长 QT综合征（aLQTS），aLQTS 在临床工作中较 cLQTS 更为常见，具有潜在致命性，是院内心源性猝死的重要原因之一。在推荐的 QT／QTc 间期延长的临界值范围内，利用不同的 QT／QTc 间期计算方法，尽量准确评估心室复极，可预测 TdP 并进一步降低猝死率。

Acquired long-QT syndrome and torsade de pointes

Long-QT syndrome(LQTS)is characterized by prolongation of ventricular repolar-ization time,and increase of inhomogeneity and dispersion.LQTS is dangerous because it may lead to torsade de pointes(TdP)and ventricular fibrillation.The clinical manifestations include syncope,tetany or sudden death.LQTS includes congenital long-QT syndrome(cLQTS)and ac-quired long-QT syndrome(aLQTS).The latter is more frequently seen in clinical practice than the former,and is potentially lethal,which makes it one of the most important reasons for sudden car-diac death in hospital.In the calculation of QT/QTc intervals,to evaluate ventricular repolariza-tion as accurately as possible in different methods within the recommended range of critical value of QT/QTc interval prolongation time can predict the occurrence of TdP and further reduce the rate of sudden death.