title: Electrocardiographic T- and U-wave discordance.
abstract: BACKGROUND
  Abundant information has been reported regarding the U wave, which almost entirely has been focused on U waves in isolation. There has been little investigation of discordant T and U waves.
  
  
  METHODS
  Of 18,750 consecutively recorded electrocardiograms, 143 patients were categorized resulting in three groups. Group A: 53 patients with negative T waves and positive U waves (Type I Discordance); Group B: 26 patients with positive T waves and negative U waves (Type II Discordance); and Group C: 63 patients with negative T and negative U waves. Each patient's chart was reviewed for relevant clinical, laboratory, and medical history.
  
  
  RESULTS
  Coronary disease was slightly more common in Group A (64%) than in Group B (46%) (P = 0.174; ns). Coronary disease in Group C was extremely common (88%; P <0.001). Hypertension in the two discordant groups was similar: Group A (60%) versus Group B (58%) (P = ns), Group C was significantly higher (88%) (P <0.001). Left ventricular hypertrophy was 49% in Group A and 58% in Group B (P = ns), but Group C was significantly higher at 70% (P = 0.038).
  
  
  CONCLUSIONS
  This appears to be the first investigation of the associations of discordant T and U waves. We found that the significance of any U wave is not independent of their respective T wave. In addition, we propose that the U wave not be analyzed in isolation, but rather with respect to its T wave.
authors.affiliation: Cardiology Division, Saint Vincent Hospital, Worcester Medical Center, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Reinig
authors.forename: Robert
authors.initials: R
authors.lastname: Harizi
authors.forename: David H
authors.initials: DH
authors.lastname: Spodick
mesh_terms: D000368:Aged; D002318:Cardiovascular Diseases / Q000503:physiopathology*; D016009:Chi-Square Distribution; D003920:Diabetes Mellitus / Q000503:physiopathology; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008297:Male; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology