Prevention,management and emergency treatment of children with long QT interval syndrome and its advanced Torsades de Pointes / 中国小儿急救医学

ABSTRACT

Long QT interval syndrome ( LQTS ) is an ion channelopathy disease which holds the characteristics of the prolongation of QT interval on electrocardiogram ( ECG ) and ventricular arrhythmia ( VT) . The occurrence of this disease is associated with mutations among potassium channel protein,sodium channel protein,calcium channel related factor,and membrane adaptation protein. Now,there were 13 genes that their mutation results in LQTS. The clinical feature is mainly manifested on the abnormal prolongation of QT interval,the giant T wave alternans on the ECG and the syncope or cardiac sudden death resulted from torsades de pointes(TdP) ventricular tachycardia. Arrhythmic events are closely related with the gene type involved. On LQTS1,the arrhythmia was normally triggered by sports and emotional excitement,and LQTS2 was by loud noises. The emergency treatment is required when the TdP occurred, because it will result in rapid deterioration of circulatory perfusion and sudden death. The emergency treatment includes intravenous administration of magnesium sulfate,synchronized or nonsynchronized DC shock for cardioversion,correcting internal environmental disturbance such as hypokalemia,and terminating the use of certain drugs which could cause the prolongation of QT interval. The long term management of LQTS includes lifestyle intervention, oral administration of β-blockers, implantation of implantable cardioverter defibrillator ( ICD ) , left cardiac sympathetic denervation and certain target drugs.