MAGNESIUM-DEFICIENCY PROLONGS MYOCARDIAL STUNNING IN AN OPEN-CHEST SWINE MODEL

The effect of magnesium deficiency on postischemic myocardial dysfunct ion (myocardial stunning) in an open-chest swine model was studied. Tw elve swine were assigned either to low magnesium diet or control diet. Myocardial stunning was assessed by measuring regional wall thickenin g by epicardial Doppler before and after brief occlusion (8 min) of th e left anterior descending coronary artery. Serum magnesium levels dec reased significantly in the experimental group only. Glutathione level s were 42.6% lower in the magnesium deficient swine than in controls. Stunning time was significantly prolonged from 32.8 +/- 3.1 min in the control group to 43.8 +/- 4.6 min in the hypomagnesemic swine. In con clusion, magnesium deficiency is associated with prolonged recovery fr om myocardial stunning.