title: Hemodiafiltration beneficially affects QT interval duration and dispersion compared to hemodialysis.
abstract: OBJECTIVE
  The prolongation of the QT interval and dispersion could predict ventricular arrhythmias. It is not yet established whether there is a difference between the effects of hemodialysis and hemodiafiltration on QT interval duration and dispersion.
  
  
  METHODS
  Data of thirty patients was investigated while they were receiving hemodiafiltration over a period of 3 months; then the same group of patients was evaluated during treatment with conventional hemodialysis for at least another 3 months. Ionic parameters and surface electrocardiograms (ECG) were analyzed five times during each session, and 2D, M-mode echocardiography and Holter ECGs were performed to acquire additional information.
  
  
  RESULTS
  QT interval duration (QTmax) and dispersion (QTd) showed a significant increase during hemodialysis, but not during hemodiafiltration. QTmax was 388.66 ± 31.81 ms at the beginning of hemodialysis and increased to 400.66 ± 39.12 ms even at the 30th minute (p < 0.05). QTd was found to be 31.33 ± 10.08 ms before the commencement of hemodialysis with the largest prolongation being seen at the 240th minute (51.33 ± 14.56 ms, p < 0.05). The occurrence of ventricular premature beats was significantly higher during hemodialysis (p = 0.018). The left atrial diameter significantly decreased at the end of hemodiafiltration (at the beginning 45.1 ± 5.25 mm, at the end 40.77 ± 5.76 mm; p < 0.05).
  
  
  CONCLUSIONS
  Our results suggest a beneficial effect of hemodiafiltration on the studied electrocardiographic parameters compared to hemodialysis. The larger decrease in the left atrial diameter suggests a more efficient intracardiac volume-decreasing potential of hemodiafiltration.
authors.affiliation: Division of Nephrology, Department of Medicine, Medical and Health Science Centre, University of Debrecen, Pf. 19. Nagyerdei Krt. 98, Debrecen, 4012, Hungary.
authors.forename: Kitti
authors.initials: K
authors.lastname: Barta
authors.forename: Árpád
authors.initials: Á
authors.lastname: Czifra
authors.forename: Csaba
authors.initials: C
authors.lastname: Kun
authors.forename: Alida
authors.initials: A
authors.lastname: Páll
authors.forename: Julianna
authors.initials: J
authors.lastname: Kulcsár
authors.forename: György
authors.initials: G
authors.lastname: Paragh
authors.forename: István
authors.initials: I
authors.lastname: Lőrincz
authors.forename: Tamás János
authors.initials: TJ
authors.lastname: Padra
authors.forename: Anupam
authors.initials: A
authors.lastname: Agarwal
authors.forename: Abolfazl
authors.initials: A
authors.lastname: Zarjou
authors.forename: Zarjou
authors.initials: Z
authors.lastname: Abolfazl
authors.forename: József
authors.initials: J
authors.lastname: Balla
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Szabó
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001145:Arrhythmias, Cardiac / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D006325:Heart Atria / Q000000981:diagnostic imaging; D017583:Hemodiafiltration / Q000379:methods*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000503:physiopathology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D006435:Renal Dialysis / Q000379:methods*; D012307:Risk Factors; D013997:Time Factors