Which of the following is a cardiac complication of anorexia nervosa?

QT prolongation is a significant cardiac complication associated with anorexia nervosa. Individuals with this eating disorder often experience electrolyte imbalances, particularly low levels of potassium (hypokalemia), magnesium (hypomagnesemia), and calcium (hypocalcemia). These imbalances can lead to alterations in cardiac conduction, particularly affecting the myocardial repolarization phase, which is reflected as QT prolongation on an electrocardiogram (ECG).

QT prolongation is concerning because it increases the risk for potentially life-threatening arrhythmias, such as torsades de pointes, which can occur due to the disrupted ionic balance that anorexia may induce. Monitoring and managing the heart's electrical activity is crucial in patients with anorexia nervosa to prevent these severe complications.

In contrast, while hypotension, arrhythmias, and heart murmurs can also occur in individuals with anorexia nervosa, they are not as directly linked to the well-known effects of electrolyte imbalances as QT prolongation is. While hypotension might result from dehydration or malnutrition, and arrhythmias could be a consequence of various factors including electrolyte disturbances, QT prolongation specifically denotes a direct effect related to the alterations caused by the disease itself. Heart murmurs may occur due to