Serum Magnesium and Ventricular Repolarization Heterogeneity: A Case-Control Study Based on Electrocardiographic...

Area of Science:

• Cardiology
• Electrophysiology
• Biochemistry

Background:

• Ventricular repolarization is crucial for cardiac electrical stability.
• Hypomagnesemia is a common electrolyte disturbance with potential cardiac implications.
• Electrocardiography (ECG) parameters like QT and Tp-e intervals reflect repolarization dynamics.

Purpose of the Study:

• To investigate changes in ventricular repolarization parameters in hypomagnesemia.
• To determine the relationship between serum magnesium levels and ECG-assessed repolarization.
• To identify if magnesium levels independently predict repolarization abnormalities.

Main Methods:

• Retrospective observational study of 160 individuals.
• Participants divided into hypomagnesemia (Mg < 1.7 mg/dL) and normomagnesemia (Mg 1.8-2.2 mg/dL) groups.
• ECG parameters including QT, QTc, Tp-e, Tp-e/QT, and Tp-e/QTc were measured and compared.

Main Results:

• Hypomagnesemia group showed significantly prolonged QT, QTc, Tp-e, Tp-e/QT, and Tp-e/QTc intervals (p < 0.001).
• Serum magnesium levels negatively correlated with QTc (r = -0.437), Tp-e (r = -0.457), Tp-e/QT (r = -0.288), and Tp-e/QTc (r = -0.281).
• Magnesium level was an independent predictor of prolonged QTc duration and Tp-e/QTc ratio.

Conclusions:

• Serum magnesium level significantly impacts ventricular repolarization duration and heterogeneity.
• Hypomagnesemia is associated with prolonged repolarization and increased heterogeneity.
• Low serum magnesium is an independent risk factor for prolonged QTc and Tp-e/QTc intervals.