Global T-wave inversions with isolated hypomagnesemia.
Ting F Tsai1, Alyssa C Browning, John Rutledge
1Department of Cardiovascular Medicine, University of California-Davis Medical Center, Sacramento, California.
The Journal of Emergency Medicine
|July 31, 2013
Summary
Isolated hypomagnesemia can cause dynamic electrocardiogram (ECG) changes, including prolonged QTc duration and T-wave inversions. Prompt magnesium correction can resolve these ECG abnormalities.
Area of Science:
- Cardiology
- Electrophysiology
- Internal Medicine
Background:
- Magnesium's role in cardiac function is not fully understood.
- Previous studies lacked clarity on isolated hypomagnesemia's ECG effects due to concurrent electrolyte imbalances.
Observation:
- A 37-year-old man with heavy alcohol use presented with syncope.
- Initial ECG revealed global T-wave inversions and prolonged QTc duration.
- Serum magnesium was low (1.1 mg/dL) with normal calcium and potassium levels.
Findings:
- The patient received magnesium infusion.
- Subsequent ECGs demonstrated resolution of T-wave inversions and QTc prolongation.
- This case highlights dynamic ECG changes in isolated hypomagnesemia.
Implications:
- Clinicians should consider checking serum magnesium in patients with unexplained prolonged QTc and T-wave inversions.
- Correcting hypomagnesemia is crucial for managing associated ECG abnormalities.
- This case contributes to understanding the direct cardiac effects of isolated magnesium deficiency.
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