Which electrolyte imbalance can cause ischemic changes on an ECG?

• A. Hypocalcemia
• B. Hyperkalemia
• C. Hypernatremia
• D. Hypomagnesemia

Answer: (B)

Hyperkalemia is known to cause significant changes on an ECG, particularly because it affects the cardiac muscle's electrical conduction and repolarization processes. Elevated potassium levels can lead to characteristic ECG findings such as peaked T waves, widened QRS complexes, and even sine wave patterns in severe cases. These changes can mimic or even be mistaken for ischemic changes, as they affect how the heart repolarizes and can impact overall cardiac rhythm and conduction.

This alteration in the cardiac action potential due to high potassium levels can result in impaired myocardial oxygen delivery, contributing to ischemic conditions. Therefore, recognizing hyperkalemia on an ECG is crucial for the timely treatment of potential cardiac complications.