What type of waves are seen on an EKG during hypokalemia?

In the context of hypokalemia, the appearance of U waves on an EKG is a hallmark finding. U waves are additional waveforms that can be seen following the T wave and represent the repolarization of the Purkinje fibers or papillary muscles in the heart. These waves become more prominent in the setting of low potassium levels because potassium plays a critical role in repolarization.

When potassium levels drop, it leads to increased myocardial excitability and disturbances in the cardiac action potential. This often results in more significant or more evident U waves. In many patients with hypokalemia, the U waves may be seen alongside flattened or even inappropriately peaked T waves, but the characteristic that stands out distinctly is the U wave.

Other EKG manifestations associated with hypokalemia include T wave flattening and possible widening of the QRS complex, but these are not as specific as the presence of U waves. Therefore, U waves serve as a key diagnostic feature in recognizing the impact of hypokalemia on cardiac repolarization.