Which arrhythmia is commonly associated with a prolonged QT interval?

Torsades de pointes is an arrhythmia that is specifically associated with a prolonged QT interval. This condition is characterized by a unique twisting of the points seen on an electrocardiogram (ECG). The prolonged QT interval can lead to abnormal repolarization of the cardiac ventricles, which predisposes the individual to this type of ventricular tachycardia. The mechanisms often involve electrolyte imbalances, congenital long QT syndromes, or effects from certain medications that can prolong the QT interval.

In contrast, bradycardia, ventricular fibrillation, and tachycardia do not have the same direct association with a prolonged QT interval. Bradycardia relates to a slow heart rate and may be due to various factors, but it is not specific to QT interval changes. Ventricular fibrillation is a life-threatening rhythm that usually occurs in the context of significant cardiac pathology rather than in relation to the QT interval specifically. Tachycardia, while an increased heart rate, also does not inherently include changes in the QT interval as a defining characteristic.