MAGNESIUM-DEFICIENCY AND CARDIOGENIC-SHOCK AFTER CARDIOPULMONARY BYPASS

Magnesium is an important cation that has a key role in cellular proce sses of energy transfer and utilization involving adenosine triphospha te, and influences cell membrane functions. Its antiarrhythmic propert ies are well-known and it is widely recognized as an adjunct for the t reatment of arrhythmias after myocardial infarction and cardiopulmonar y bypass. Magnesium may influence hemodynamic performance through its effects on vascular tone, modulation of intracellular calcium, regulat ion of catecholamine activity, and its essential role in adenosine tri phosphate metabolism. The potential for magnesium deficiency to affect cardiovascular performance may be especially relevant in ischemic sta tes. We report a case of cardiogenic shock developing after cardiopulm onary bypass that was initially unresponsive to therapeutic interventi on, but that resolved promptly after magnesium administration. The pot ential role of magnesium in enhancing hemodynamic performance is discu ssed, with a review of its cellular metabolic properties and activitie s. (C) 1997 by The Society of Thoracic Surgeons.