1) A syndrome characterized by history of syncopal episodes and a long QT interval, sometimes leading to sudden death due to paroxysmal ventricular arrhythmia. A form associated with autosomal recessive inheritance and congenital deafness is called the JERVELL-LANGE NIELSEN SYNDROME. An autosomal dominant form without deafness is called the ROMANO-WARD SYNDROME.

2) prolongation of Q-T interval combined with torsades de pointes and manifests as several different forms; may be acquired or congenital; may lead to serious arrhythmia and sudden cardiac death.

3) Any of several inherited cardiac arrhythmias that are characterized by abnormal duration and shape of the QT interval and that place the subject at risk for torsades de pointes -- abbreviation LQTS.