Abnormalities in the U wave and T-U segment on ECG are indicative of ischemia, strain, or functional derangement of the papillary muscles.
The U wave is considered to represent repolarization of the papillary muscle and neighboring structures. In this study the various types of abnormalities in U wave and T-U segments are outlined and are related to the cardiac involvement. The common factor underlying the varied cardiac pathology is regarded to be ischemia, "strain," or other functional derangement of the papillary muscles in the right or left ventricles.
Furbetta et al. (Sat,) studied this question.