Oral Magnesium Therapy Improves Endothelial Function in Patients With Coronary Artery Disease

Background—Magnesium blocks many of the physiological actions of calcium. Nevertheless, the impact of magnesium supplementation on endothelial function and exercise tolerance in stable coronary artery disease (CAD) patients has not been assessed. Methods and Results—In a randomized, double-blind, placebo-controlled trial, 50 stable CAD patients (41 men and 9 women, mean±SD age 67±11 years, age range 42 to 82 years) were randomized to receive either magnesium (n=25) (30 mmol/d Magnosolv-Granulat; Asta Medica Company, Inc) or placebo (n=25) for 6 months. Before and after 6 months, endothelium-dependent brachial artery flow-mediated vasodilation (FMD) and endothelium-independent NTG-mediated vasodilation were assessed with high-resolution (10-MHz) ultrasound. Exercise stress testing was performed with use of the Bruce protocol. Intracellular magnesium concentrations ([Mg2+]i) were assessed from sublingual cells through x-ray dispersion (EXA) (normal mean±SD values 37.9±4.0 mEq/L). The magnesium therapy signi...