[Congenital (hereditary) long QT syndrome: possible factors predisposing to development of ventricular tachyarrhythmias. Part II]. / Vrozhdennyi (nasledstvennyi) sindrom udlinennogo intervala Q-T: vozmozhnye faktory, predraspolagaiushchie k razvitiiu zheludochkovykh takhiaritmii. Chast. II.

In 3 close relatives (mother, son, mother's first cousin) with long Q-T syndrome syncopal attacks were preceded by lowering of ionized calcium in peripheral blood. This mechanism is supposed to be a trigger of ventricular tachycardia in long Q-T syndrome.