Korean J Crit Care Med.  2008 Dec;23(2):102-105. 10.4266/kjccm.2008.23.2.102.

Mental Change, Cardiovascular Depression and QT Prolongation Caused by Severe Hypermagnesemia: A Case Report

• Choi HO
• Lee SG
• Lee PH
• Lim SN
• Sohn BS
• Chung YH
• Nam GB

• KMID: 2228402
• DOI: http://doi.org/10.4266/kjccm.2008.23.2.102

Abstract

A 50-year-old woman was referred to our hospital for evaluation of mental change and general weakness accompanied by an irregular and weak pulse. She had previously been diagnosed with Bartter's syndrome and had taken potassium-sparing diuretics. She had developed constipation that had led to abdominal pain and had taken excessive magnesium oxide over a long time. On admission, she was lethargic. Her blood pressure (BP) was 130/74 mmHg, with a heart rate varying from 30 to 78 beats/min. An electrocardiogram (ECG) revealed several abnormalities, including first degree AV block, QT prolongation, sinus pause with a junctional rhythm, and paroxysmal tachycardia alternating with sinus pause. Her serum concentration of magnesium was markedly elevated to 16.19 mg/dl. Hemodialysis and a calcium gluconate infusion was attempted to reduce magnesium levels and to counteract the cardiovascular effect of magnesium. As magnesium levels declined, her general medical condition improved and her ECG changes were normalized. Severe hypermagnesemia should be suspected as the cause of mental change, cardiovascular dysfunction, and variable ECG changes.

Keyword

hypermagnesemia; magnesium oxide

MeSH Terms

Abdominal Pain
Atrioventricular Block
Bartter Syndrome
Blood Pressure
Calcium Gluconate
Constipation
Depression
Diuretics
Electrocardiography
Female
Gluconates
Heart Rate
Humans
Magnesium
Magnesium Oxide
Middle Aged
Renal Dialysis
Tachycardia, Paroxysmal
Calcium Gluconate
Diuretics
Gluconates
Magnesium
Magnesium Oxide