Which electrolyte imbalance can cause arrhythmias?

Which electrolyte imbalance can cause arrhythmias?

• A. Sodium imbalance
• B. Potassium imbalance
• C. Calcium imbalance
• D. Magnesium imbalance

Answer: (B)

Potassium sets the heart’s resting membrane potential and governs how quickly cardiac cells repolarize. When potassium levels are off, the electrical gradient across heart cells changes, altering excitability and conduction. If potassium is too high, the resting potential becomes less negative, conduction slows, and you can see ECG changes that progress to life-threatening rhythms. If potassium is too low, cells become more hyperpolarized, repolarization is prolonged, and the heart becomes prone to ectopy and other arrhythmias. Because these shifts directly destabilize the heart’s rhythm, a potassium imbalance is a well-known cause of arrhythmias. While calcium and magnesium disturbances can also affect rhythm, potassium imbalance has the strongest and most direct link to arrhythmic risk.

Potassium sets the heart’s resting membrane potential and governs how quickly cardiac cells repolarize. When potassium levels are off, the electrical gradient across heart cells changes, altering excitability and conduction. If potassium is too high, the resting potential becomes less negative, conduction slows, and you can see ECG changes that progress to life-threatening rhythms. If potassium is too low, cells become more hyperpolarized, repolarization is prolonged, and the heart becomes prone to ectopy and other arrhythmias. Because these shifts directly destabilize the heart’s rhythm, a potassium imbalance is a well-known cause of arrhythmias. While calcium and magnesium disturbances can also affect rhythm, potassium imbalance has the strongest and most direct link to arrhythmic risk.