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PubMed · 2869081

QT interval prolongation.

J L Scott·R M Walls
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Abstract

The QT interval is a function of ventricular repolarization time and is measured from the onset of the QRS complex to the end of the T wave. The length of this interval is inversely related to heart rate. A prolonged QT interval is most often secondary to the use of Type I antidysrhythmic medications (quinidine, procainamide). It is also associated with phenothiazines, organophosphates, hypocalcemia, liquid protein diets and the congenital long QT syndromes. QT prolongation is associated with a variety of ventricular dysrhythmias, most characteristically Torsades des pointes. Treatment consists of correction of the underlying metabolic disorder or discontinuation of the offending medication.

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Adrenergic beta-AntagonistsAnti-Arrhythmia AgentsAntidepressive Agents, TricyclicArrhythmias, CardiacDiagnosis, DifferentialElectrocardiographyHumansHyperkalemiaHypnotics and SedativesLong QT SyndromeTachycardiaJournal Article

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J L Scott, R M Walls. 1985. QT interval prolongation.. https://doi.org/10.1016/0736-4679(85)90076-9

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