Which electrolyte imbalance can lead to cardiac arrhythmias?

Hyperkalemia, characterized by elevated levels of potassium in the blood, has a significant impact on cardiac function and can lead to various forms of cardiac arrhythmias. Potassium is essential for maintaining normal electrical activity in the heart. Changes in potassium levels can disrupt this balance and affect the heart's rhythm.

In particular, high potassium levels can decrease the resting membrane potential of cardiac cells, which can lead to delayed depolarization and increased excitability. This can manifest as changes in the electrocardiogram (ECG), such as peaked T-waves, widening of the QRS complex, and even ventricular fibrillation in severe cases. Therefore, hyperkalemia poses a serious risk for the development of life-threatening arrhythmias.

In contrast, while other electrolyte imbalances such as hypocalcemia, hyponatremia, and hypercalcemia can also have various effects on cardiac function, they are less directly associated with the immediate risk of arrhythmias compared to hyperkalemia. Hence, understanding the role of potassium in cardiac electrical activity highlights why hyperkalemia is particularly noted for leading to arrhythmic events.