title: Evaluation of QT parameters in patients of thalassaemia major with iron overload.
abstract: OBJECTIVE
  To study QT parameters in Thalassaemia Major patients and their association with serum ferritin levels.
  
  
  METHODS
  This cross-sectional study was conducted at Ziauddin University, Karachi, from February 2013 to September 2014, and comprised patients of Thalassaemia Major. Participants' serum ferritin levels were determined and electrocardiography was performed. Data was analysed using SPSS 20.
  
  
  RESULTS
  Of the 135 participants, 68(50.4%) were in the 7-14 years age group and 69(51%) were males. Significant prolongation of QT, corrected QT interval and increased QT dispersion was observed in patients with serum ferritin levels more than 2,500 nanogram/millilitre (p<0.001 each). These measurements of corrected QT and QT dispersion had a positive linear correlation with serum ferritin levels (r=0.760 and 0.786).
  
  
  CONCLUSIONS
  Electrocardiography could be a useful means for the pre-clinical detection of cardiac involvement due to iron overload in Thalassaemia Major patients.
authors.affiliation: Department of Physiology, Ziauddin University, Karachi, Pakistan.
authors.forename: Amna
authors.initials: A
authors.lastname: Faruqi
authors.affiliation: Department of Cardiology, Ziauddin University, Karachi, Pakistan.
authors.forename: Syed Imran
authors.initials: SI
authors.lastname: Ahmad
authors.affiliation: Department of Physiology, Ziauddin University, Karachi, Pakistan.
authors.forename: Syed Tousif
authors.initials: ST
authors.lastname: Ahmed
mesh_terms: D000293:Adolescent; D002648:Child; D042241:Early Diagnosis; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D005293:Ferritins / Q000097:blood*; D006331:Heart Diseases / Q000175:diagnosis / Q000209:etiology; D006801:Humans; D019190:Iron Overload / Q000097:blood / Q000209:etiology / Q000503:physiopathology; D008297:Male; D010154:Pakistan; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D017086:beta-Thalassemia / Q000150:complications*
chemical_list: D005293:Ferritins
keywords: Thalassaemia major, TM, Iron overload, Cardiac iron, Ferritin, QT interval.