Magnesium decreases cardiac injury in patients undergoing coronary artery bypass surgery

Abstract

BackgroundThe calcium-channel blocking effect of magnesium might have protective effects in patients undergoing cardiopulmonary bypass surgery. We assessed the effects of magnesium on hearts undergoing coronary artery bypass surgery with intermittent warm blood hyperkalemic cardioplegia in the antegrade fashion.Patients and MethodsTwenty patients undergoing coronary bypass surgery were randomly divided into two groups, a control group who received intermittent antegrade warm blood hyperkalemic cardioplegia for myocardial protection, and a study group who received the same solution with the addition of magnesium to the cardioplegia. Extracellular substrates (creatinine Phosphokinase, creatinine phosphokinase-MB group, lactate dehydrogenase, c-reactive protein, and cardiac troponin I were measured preoperatively and postoperatively.ResultsThere were significant differences in the post-operative concentrations of creatinine phosphokinase, creatinine phosphokinase-MB group, c-reactive protein, and lactate dehydrogenase after cardiopulmonary bypass (P<0.001 ) in the study group compared with the control subjects. Cardiac troponin I levels were also significantly lower in the study group after cardiopulmonary bypass (P<0.005).ConclusionsOur study indicates that if magnesium is added to intermittent antegrade warm blood hyperkalemic cardioplegia, blood levels of many markers of cardiac myocardial injury after cardiopulmonary bypass are lowered. This finding may have implications for myocardial protection.

Effect of magnesium supplements on serum C-reactive protein: a systematic review and meta-analysis

“…Several of the included studies were characterized by a lack of information about allocation concealment ( n = 1) or blinding of outcome assessment ( n = 2). However, one study had a moderate risk of bias [ 27 ] and other evaluated studies had a low risk of bias according to selective outcome reporting. Details of the quality of bias assessment are shown in Table II .…”

“…Participants in one study were only female [ 30 ], while the proportion of females in five studies ranged from 29% [ 8 ] to 78% [ 29 ]. In two studies the percentage of women was unknown [ 27 , 31 ]. The mean age of participants ranged from 18 [ 31 ] to 85 years [ 29 ].…”

“…The mean age of participants ranged from 18 [ 31 ] to 85 years [ 29 ]. The range of duration of the supplementation intervention across studies was from 8 h [ 27 ] to 6.5 months [ 32 ]. The consumed range of Mg dose in these studies was from 320 [ 29 ] to 1500 [ 27 ] mg/day.…”

“…The range of duration of the supplementation intervention across studies was from 8 h [ 27 ] to 6.5 months [ 32 ]. The consumed range of Mg dose in these studies was from 320 [ 29 ] to 1500 [ 27 ] mg/day. The baseline level of the CRP varied between the studies from 0.42 mg/dl [ 6 ] as minimum to 9.4 mg/dl [ 7 ] as maximum, Table III .…”

Does Magnesium-Supplemented Cardioplegia Reduce Cardiac Injury? A Meta-Analysis of Randomized Controlled Trials

“…Several studies have found that the enrichment of blood with magnesium improves hospital outcomes, 2 reduces new-onset postoperative atrial fibrillation, [3][4][5][6] and reduces the release of postoperative cardiac enzymes. [4][5][6][7] However, a retrospective study found comparable outcomes in an elderly population, 8 and other studies have shown that magnesium administration is harmful to patients with a left ventricular ejection fraction below 40%, 9 renal dysfunction, 10 or a tendency to bleed. 11 A Cochrane review of intravenous magnesium administration after acute myocardial infarction demonstrated that this practice was unlikely to reduce ischemic reperfusion injury.…”