Flattened or inverted T waves with prominent U waves are typical of which electrolyte disturbance?

Prepare for the Cleveland Clinic EKG Test with flashcards and multiple choice questions. Gain insights with hints and explanations. Ace your exam today!

Multiple Choice

Flattened or inverted T waves with prominent U waves are typical of which electrolyte disturbance?

Potassium levels strongly influence how the ventricles repolarize on the ECG. When potassium is low, the T waves tend to flatten or invert, and a prominent U wave often follows the T wave. This combination—flattened/inverted T waves with distinct U waves—is the classic pattern for hypokalemia. If you compare other electrolyte disturbances, hyperkalemia usually shows tall, peaked T waves with widening of the QRS as potassium rises, not U waves. Hypercalcemia tends to shorten the QT interval rather than produce prominent U waves. Hypomagnesemia can cause QT prolongation and torsades de pointes, but the specific bunched appearance of flat/inverted T waves with prominent U waves points more directly to low potassium. So, the described ECG pattern best fits hypokalemia.

Potassium levels strongly influence how the ventricles repolarize on the ECG. When potassium is low, the T waves tend to flatten or invert, and a prominent U wave often follows the T wave. This combination—flattened/inverted T waves with distinct U waves—is the classic pattern for hypokalemia.

If you compare other electrolyte disturbances, hyperkalemia usually shows tall, peaked T waves with widening of the QRS as potassium rises, not U waves. Hypercalcemia tends to shorten the QT interval rather than produce prominent U waves. Hypomagnesemia can cause QT prolongation and torsades de pointes, but the specific bunched appearance of flat/inverted T waves with prominent U waves points more directly to low potassium.

So, the described ECG pattern best fits hypokalemia.

More practice questions