Correlation of magnesium deficiency with C-reactive protein in elective cardiac surgery with cardiopulmonary bypass for ischemic heart disease

Background and objective: Cardiac surgery is associated with systemic inflammatory response, which is triggered by cardiopulmonary bypass (CPB) and possibly with underlying magnesium deficiency. Animal studies have shown that magnesium deficiency intensifies oxidative stress and inflammatory processes. We aimed to find a link between serum, erythrocyte, cardiac tissue magnesium concentration and C-reactive protein (CRP) as an inflammatory marker in patients undergoing elective cardiac surgery with CPB.
Materials and methods: The data of 27 patients undergoing elective cardiac surgery with CPB for ischemic heart disease were analyzed. Measurements were taken at the baseline, i.e., 24 h before surgery (serum magnesium, CRP); time point 1, before CPB (serum, erythrocyte and cardiac tissue magnesium); time point 2, after CPB (serum, erythrocyte and cardiac tissue magnesium), and time point 3, 15–17 h after surgery (serum, erythrocyte magnesium, CRP).
Results: There was a negative correlation between baseline serum magnesium and baseline CRP (P = 0.009; r = 0.492), negative correlation between cardiac tissue magne- sium at the time point 1 and baseline CRP (P = 0.021; r = 0.443), and positive correlation between CRP at time point 3 and erythrocyte magnesium at time point 2 (P < 0.001; r = 0.637).
Conclusions: The data of our study verify that inflammatory marker CRP and magnesium concentration in serum and cardiac tissue before the surgery are inversely related in patients undergoing elective cardiac surgery with CPB. Well-planned further studies are needed to evaluate the importance of underlying magnesium deficiency on the severity of systemic inflammatory response and postoperative complications after surgery with CPB.