RESUMO
Objective To study the mode and clinical implications of onset of spontaneous tosade de pointes in the congenital long QT syndrome. Methods We reviewed electrocardiograms (ECGs) of 55 patients with congenital QT syndrome for syncope. Documentation of the onset of tosade de pointes was available for 16 patients. All these patients had "definitive long QT syndrome" by accepted clinical and ECG criteria. Results One hundren and forty-nine runs of tosade de pointes were documented in 16 patients,of whom,there were 130 runs of pause-dependent tosade de pointes. Conclusion Our results show that the pause-dependent tosade de pointes,which has been recognized as a hallmark of tosade de pointes in the acquired long QT syndrome,plays a major role in the genesis of tosade de pointes in the congenital long QT syndrome.