Electrolyte concentration during haemodialysis and QT interval prolongation in uraemic patients

Europace. 2008 Jun;10(6):771-7. doi: 10.1093/europace/eun028. Epub 2008 Feb 19.


Aims: To assess the effect of different combinations of potassium and calcium concentrations on QT interval in the dialysis bath in uraemic patients.

Methods and results: Sixteen haemodialysis (HD) patients underwent a 24 h Holter recording before and during HD sessions with six randomized combinations of electrolytes concentrations of the dialysis bath (K(+), 2 and 3 mmol/L; Ca(2+), 1.25, 1.5, and 1.75 mmol/L). The effect of different dialysis baths on QT interval was significant (P < 0.05). The longest mean QTc was observed with the lowest K(+) (2 mmol/L) and Ca(2+) concentrations (1.25 mmol/L), whereas the shortest mean QTc was observed with the highest K(+) (3 mmol/L) and Ca(2+) concentrations (1.75 mmol/L). QTc was >440 ms in 9 of 16 patients (56%) at the lowest Ca(2+) and K(+) concentrations, and in 3 of 16 patients (18%) at the highest electrolytes level. Changes in QTc during the HD sessions were inversely correlated with that in total Ca and Ca(2+) plasma concentrations (P < 0.0001).

Conclusion: Changes in ventricular repolarization duration associated with HD largely depend on the concentrations of Ca(2+) and K(+) in the dialysis bath. These findings may have important implications for the choice of the electrolytes concentration of the dialysis bath during the HD session.

Publication types

  • Clinical Trial

MeSH terms

  • Aged
  • Calcium / analysis*
  • Dialysis Solutions / chemistry*
  • Female
  • Humans
  • Long QT Syndrome / complications
  • Long QT Syndrome / diagnosis*
  • Male
  • Potassium / analysis*
  • Renal Dialysis*
  • Tomography, X-Ray Computed*
  • Uremia / complications
  • Uremia / rehabilitation*


  • Dialysis Solutions
  • Potassium
  • Calcium