a very dangerous form of *ventricular tachycardia characterized by a sinusoidal (twisting) pattern on the electrocardiogram due to a constantly shifting cardiac electrical vector (hence the French term, meaning ‘twisting of points’). It is usually a side-effect of medication but may also occur in patients with severe deficiency of potassium or magnesium or inherited abnormalities of the cardiac electrical system. See long QT syndrome.
prolongation of the *Q–T interval on the electrocardiogram. It indicates susceptibility to ventricular tachycardia (especially *torsades de pointes), ventricular fibrillation, and sudden death. It may be familial or caused by certain drugs (e.g. sotalol, amiodarone, certain antipsychotic drugs).... long qt syndrome
(VT) a dangerously fast beating of the heart stemming from an abnormal focus of electrical activity in the *ventricles. The electricity does not pass through the heart along the usual channels and as a result the contraction of the heart muscle is often not as efficient as normal, which can result in a sudden drop in blood pressure or even *cardiac arrest. Left untreated it will prove ultimately fatal. See also arrhythmia; torsades de pointes.... ventricular tachycardia
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