What electrocardiographic change is commonly seen with hypocalcemia?

What electrocardiographic change is commonly seen with hypocalcemia?

• A. Prolonged QT interval
• B. Shortened QT interval
• C. Prolonged QRS duration
• D. Peaked T waves

Answer: (A)

Hypocalcemia lengthens the QT interval on the ECG because low extracellular calcium prolongs the ventricular repolarization phase, extending the ST segment. This QT prolongation is the classic sign of low calcium. Other patterns don’t fit hypocalcemia: a short QT suggests high calcium; a prolonged QRS duration points to conduction problems or other electrolyte disturbances; peaked T waves are typical of hyperkalemia. So the prolonged QT interval is the best description of the ECG change seen with hypocalcemia.

Hypocalcemia lengthens the QT interval on the ECG because low extracellular calcium prolongs the ventricular repolarization phase, extending the ST segment. This QT prolongation is the classic sign of low calcium. Other patterns don’t fit hypocalcemia: a short QT suggests high calcium; a prolonged QRS duration points to conduction problems or other electrolyte disturbances; peaked T waves are typical of hyperkalemia. So the prolonged QT interval is the best description of the ECG change seen with hypocalcemia.