title: Effects of weight loss on QT interval in morbidly obese patients.
abstract: BACKGROUND
  Obesity causes structural changes to the heart that may influence its function. Furthermore, morbid obesity is associated with an acquired prolongation of the QTc interval that may lead to potentially hazardous arrhythmias. The present study investigated the effect of body weight loss following vertical banded gastroplasty (VBG) on the QTc interval.
  
  
  METHODS
  17 morbidly obese patients, scheduled for elective VBG, were studied before the operation and 8-10 months postoperatively, when each patient had achieved a weight loss of >/= 25% of the preoperative body weight.
  
  
  RESULTS
  15 patients achieved significant body weight loss of >/= 25% within the first 8-10 postoperative months (P <0.001). This weight loss, corresponding to an excess weight loss of 48.7% and a mean body mass index (BMI) reduction from 49.7 kg/m2 to 36.6 kg/m2, was followed by significant shortening of the QTc interval from 428 msec to 393 msec (P <0.001).
  
  
  CONCLUSIONS
  The significant postoperative weight loss following VBG was accompanied by shortening of the QTc interval. This effect is expected to reduce the incidence of fatal conditions associated with the long QT syndrome, such as malignant ventricular arrhythmias and sudden death, and therefore improve morbidity and mortality.
authors.affiliation: Department of Anesthesiology, Cardiology and Surgical Oncology, University Hospital of Heraklion, Crete, Greece.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Papaioannou
authors.forename: Dimitris
authors.initials: D
authors.lastname: Michaloudis
authors.forename: Othon
authors.initials: O
authors.lastname: Fraidakis
authors.forename: Anastasios
authors.initials: A
authors.lastname: Petrou
authors.forename: Fotini
authors.initials: F
authors.lastname: Chaniotaki
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Kanoupakis
authors.forename: Georgia
authors.initials: G
authors.lastname: Stamatiou
authors.forename: John
authors.initials: J
authors.lastname: Melissas
authors.forename: Helen
authors.initials: H
authors.lastname: Askitopoulou
mesh_terms: D000328:Adult; D001145:Arrhythmias, Cardiac / Q000517:prevention & control*; D004562:Electrocardiography; D005260:Female; D015391:Gastroplasty; D006321:Heart / Q000502:physiology*; D006801:Humans; D008133:Long QT Syndrome; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000503:physiopathology* / Q000601:surgery; D011446:Prospective Studies; D015431:Weight Loss / Q000502:physiology*