The Study of Serum Calcium to Magnesium Ratio in Patients with Acute Coronary Syndrome in a Tertiary Hospital, Hubli, Karnataka

BACKGROUND Cardiovascular diseases are one of the leading causes of morbidity and mortality worldwide. High Ca levels and low Mg levels are associated with increased cardiovascular risk in the general population.1 The balance between Ca and Mg seems to play an important role in homeostasis since Mg is considered as physiologic antagonist of Ca.2 Hence Ca/Mg ratio was considered to study its association with acute coronary syndrome (ACS). METHODS This is a case control study conducted in Karnataka Institute of Medical Sciences, Hubli over a period of 2 years, February 2019 to December 2020. 200 cases and 150 controls were included in the study. The biochemical measurements including complete blood count (CBC), cardiac biomarkers, liver function tests, renal function tests (RFT), serum electrolytes and lipid profile were measured using standard laboratory methods. Student ‘t’ test was used to compare the data. Optimum cut-offs for diagnosis of acute myocardial infarction was calculated using receiver operating characteristics (ROC) analysis. The association among markers was established by calculating Pearson’s correlation. RESULTS Serum Ca/Mg ratio was significantly higher (p value < 0.001) in ACS when compared to control groups. It was also found that Ca/Mg ratio was significantly lower (p value < 0.001) in non-ST elevation myocardial infarction (NSTEMI) when compared to STEMI group. Serum Mg was significantly lower (p value < 0.001) in ACS group when compared to control group. Significant correlation (p value < 0.05) was found between serum Ca/Mg ratio and cardiac markers (CKMB, Troponin-I). ROC analysis of Ca/Mg (4.19) ratios showed optimum cut-offs in diagnosis of AMI. CONCLUSIONS Serum Ca/Mg could be useful adjuvant marker in diagnosis of AMI. The ratio is higher in ST-segment elevation myocardial infarction when compared to non-STsegment myocardial infarction, which could be due to greater decrease in Mg levels when compared Ca in ACS. KEYWORDS ST Elevation Myocardial Infarction (STEMI), Non ST Elevation Myocardial Infarction (NSTEMI), Calcium (Ca), Magnesium (Mg), Acute Coronary Syndrome (ACS), Creatine Kinase-MB (CK-MB).