U wave: facts, hypotheses, misconceptions, and misnomers.
The clinical significance of U wave is limited to the occasional obfuscation of the end of T wave and an inadequately explained U wave inversion associated with myocardial ischemia, infarction, and ventricular hypertrophy and dilatation. Lengthening of QT interval often interferes with the recognition of U wave. The characteristics of U wave are not compatible with the Purkinje or ventricular muscle repolarization hypotheses. The timing of the U wave during ventricular relaxation and the links between U wave and mechanical events favor the mechanoelectrical hypothesis of U wave genesis. Unfortunately, little research has been done to test this hypothesis.
Surawicz
B
B
Krannert Institute of Cardiology, Indiana University School of Medicine, Indianapolis, USA.
D000200:Action Potentials; D000328:Adult; D001696:Biomechanical Phenomena; D006332:Cardiomegaly / Q000150:complications / Q000503:physiopathology; D002311:Cardiomyopathy, Dilated / Q000150:complications / Q000503:physiopathology; D003971:Diastole; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006339:Heart Rate; D006352:Heart Ventricles / Q000503:physiopathology*; D006801:Humans; D008297:Male; D017202:Myocardial Ischemia / Q000150:complications / Q000503:physiopathology; D017180:Tachycardia, Ventricular / Q000209:etiology / Q000503:physiopathology*