European Journal of Clinical Pharmacology

, Volume 38, Issue 2, pp 107–110 | Cite as

Oral magnesium reduces ventricular ectopy in digitalised patients with chronic atrial fibrillation

  • R. V. Lewis
  • B. Tregaskis
  • J. McLay
  • E. Service
  • D. G. McDevitt


We have examined the effects of magnesium replacement therapy upon post-exercise heart rate and incidence of ventricular premature beats (VPB) in digitalised patients with AF. In 11 such patients, all of whom had serum magnesium concentrations of less than 0.85 mmol/l, treatment with magnesium glycerophosphate was associated with a significant reduction in number of VPBs (982 v. 416 VPB/24 h). Five patients had a high prevalence of ventricular ectopy (>300 VPB/24 h) and these subjects showed particularly marked decreases in VPBs during magnesium treatment (1998 v. 690 VPB/24 h). Three patients had slightly increased QTc intervals but these did not change during magnesium replacement. No significant changes were seen in the mean post-exercise heart rate although 2 subjects did show falls of 25% of more during magnesium replacement.

We conclude that treatment with magnesium glycerophosphate may be associated with a decreased prevalence of ventricular ectopy in some digitalised patients with chronic AF and mild-moderate hypomagnesaemia.

Key words

magnesium ventral ectopy atrial fibrillation digitalised patients 


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Copyright information

© Springer-Verlag 1990

Authors and Affiliations

  • R. V. Lewis
    • 1
  • B. Tregaskis
    • 1
  • J. McLay
    • 1
  • E. Service
    • 1
  • D. G. McDevitt
    • 1
  1. 1.Department of Clinical PharmacologyNinewells Hospital and Medical SchoolDundeeScotland UK

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