Role of serum magnesium levels in cardiac arrhythmias

Abstract

Background: Magnesium deficiency leads to enhanced vascular endothelial injury and promotes platelet-dependent thrombosis.It has possible involvement in stent thrombosis. Theoretically serum Mg levels have been shown to decline after cardiopulmonary bypass and do not recover to preoperative levels until 3 to 5 days after surgery, which coincides with the period during which most cases of AF develop. In this context, this prospective study was conducted with aims and objectives to review and evaluate the role of serum magnesium levels in cardiac arrhythmias and whether to include serum magnesium level monitoring as routine investigation. Methods: A Prospective study done at Sri Jayadeva Institute of Cardiovascular Sciences and Research, Bangalore, from January 2016 to December 2017. Hundred patients with normal sinus rhythm who had undergone treatment, in preoperative, intraoperative and postoperative period, undergoing procedures in cath lab; who had arrhythmias, during the course of treatment were included in the study .they were monitored with Standard ECG, Arterial blood pressure and hemodynamic parameters .Venous blood sample was drawn and sent to Lab and serum magnesium level was measured and subjected to statistical analysis. Data variables comparison was done by ANNOVA test and their relationship was evaluated using correlation tests. Results: Majority of the patients were males and 52% patients were above 61 year age. Among the study patients 66% had Coronary Atherosclerotic Diseases. and 44% patients had other cardiac diseases like valvular heart diseases, Atrial Septal Defect and Ventricular Septal Defects.significant number (79%) of patients had arrhythmias during Post operative period, compared to Pre and Intra operative period with 12% and 6% respectively. 61% of the patients had Atrial Fibrillation and 38% had ventricular fibrillation during post operative period. Significant number of patients (58%) had low serum Magnesium levels during arrhythmia with P value of <0.05. 65% of post operative cardiac patients had significantly low serum Magnesium levels with P value of <0.05 .66% of patients with AF had significantly low magnesium value (p<0.05). In this study group post operative patients who had low serum magnesium level had significantly more incidences of arrhythmias with mean level of serum Magnesium <1.8 mg/dl. patients with low serum Magnesium levels had significantly higher incidence of Atrial Fibrillation. Conclusions:In light of its simplicity, cost-effectiveness and safety, monitoring the serum magnesium level is another first-line option for management of patients with arrhythmias in the intraoperative, perioperative, postoperative setup in hospitalized cardiac patients.