Congenital long QT syndrome has a tendency to develop the following condition:
**Core Concept**
Congenital long QT syndrome is a genetic disorder characterized by a prolongation of the QT interval on the electrocardiogram (ECG). This condition is associated with an increased risk of life-threatening arrhythmias, particularly Torsades de Pointes, which can degenerate into ventricular fibrillation and sudden cardiac death.
**Why the Correct Answer is Right**
The underlying pathophysiology of congenital long QT syndrome involves a mutation in genes that encode for cardiac ion channels, particularly potassium (K+) and sodium (Na+) channels. These mutations disrupt the normal functioning of these channels, leading to an abnormal prolongation of the action potential duration and the QT interval on the ECG. The most common gene mutations associated with long QT syndrome are in the KCNQ1, KCNH2, and SCN5A genes.
**Why Each Wrong Option is Incorrect**
* **Option A:** While sudden cardiac death is a potential complication of congenital long QT syndrome, it is not the most common condition associated with this disorder.
* **Option B:** Hypokalemia can exacerbate the prolongation of the QT interval, but it is not a direct complication of congenital long QT syndrome.
* **Option C:** While Torsades de Pointes is a potential arrhythmia associated with congenital long QT syndrome, it is not the condition that is most directly related to the syndrome.
**Clinical Pearl / High-Yield Fact**
A key aspect of managing patients with congenital long QT syndrome is avoiding triggers that can prolong the QT interval, such as medications that block potassium channels (e.g., sotalol, dofetilide), and ensuring adequate potassium levels.
**Correct Answer: Torsades de Pointes.**