Which arrhythmia is characterized by a consistently prolonged QT interval?

A consistently prolonged QT interval is a significant feature of Torsades de Pointes, which is a specific type of polymorphic ventricular tachycardia. This arrhythmia often arises from abnormalities in cardiac repolarization, notably associated with prolonged QT syndrome. In individuals with this condition, factors that can contribute to QT prolongation include congenital syndromes, medication use, or electrolyte imbalances.

The Torsades de Pointes rhythm itself is notable for its twisting pattern on the electrocardiogram, reflecting the rapid alternation of the electrical axis. The prolonged QT interval increases the risk for this dangerous arrhythmia, as it can lead to heterogeneous repolarization in the myocardium, which is a prerequisite for the development of Torsades de Pointes.

In contrast, atrial fibrillation, ventricular fibrillation, and supraventricular tachycardia do not share this distinctive characteristic of a prolonged QT interval as part of their defining attributes. Atrial fibrillation is an irregularly irregular rhythm without a consistent atrial or ventricular contraction sequence. Ventricular fibrillation is typically characterized by chaotic electrical activity in the ventricles, and supraventricular tachycardia is due to reentrant circuits or increased automaticity