THE IDIOPATHIC LONG QT SYNDROME AS A CAUS E OF EPILEPTIC AND NONEPILEPTIC ATTACKS

The long QT syndrome (LQTS) is characterized by a pathological lengthe ning of the corrected QT interval on the surface ECG and the occurrenc e of syncopal attacks, sometimes presenting as a seizure disorder. The y are caused by ventricular tachycardia of the torsade de pointes type , an arrhythmia that is also responsible for the high incidence of sud den death among these patients. Besides the acquired forms of LQTS whi ch are transient (e.g. therapy with QT-prolonging drugs), congenital v ariants (Romano-Ward syndrome, Jervell/ Lange-Nielsen syndrome, sporad ic form) can occur as well. The latter mostly become manifest during c hildhood or adolescence. Because the syndrome is rare, it is often not included in the primary differential diagnosis of syncope. Thus, misi nterpretation as epilepsy may occur. Especially if siblings are affect ed, a genetic epilepsy may be diagnosed. However, the correct diagnosi s can be made by standard ECG methods. Early recognition of the syndro me is very importance because of prognostic and therapeutic consequenc es. In this article, two cases of idiopathic LQTS are presented. Probl ems regarding differential diagnosis and therapy are discussed.