Prognostic Significance of Baseline Serum Calcium Levels in Patients with Acute Coronary Syndrome- An Observational Study

Abstract

Introduction: The risk stratification is very important for the management of patients with Acute Coronary Syndrome (ACS). Extraskeletal calcium plays a critical role in a range of biological processes. There is an urgent need to accurately identify, the additional factors which are important in the clinical course and outcome of patients of ACS. Aim: To evaluate impact of baseline serum calcium levels in patients with ACS and to determine prognostic significance of baseline serum calcium levels in patients with ACS. Materials and Methods: The present observational study was conducted on 100 patients of ACS, over a period of one year from December 2018 to December 2019 at Acharya Shri Chander College of Medical Sciences, Sidhra, Jammu and Kashmir, India. They were divided into three tertile ranges as: hypocalcaemic (<8.1), normocalcaemic (8.1-10.4), hypercalcaemic (>10.4). The clinical outcome was measured in terms of Left Ventricular Ejection Fraction (LVEF) development of acute pulmonary oedema, rates of emergency revascularisation, development of arrhythmias, recurrence of chest pain, mortality within 7 days of admission, readmission rates with reinfarction or any other cardiovascular complication and finally, mortality within 90 days of follow-up. Quantitative variables were compared using ANOVA/Kruskal Wallis Test between the three groups. Results: The mean age of the study population was 73.29±8.11 years. Baseline calcium on admission was found to be <8.1 mg/dL in ACS patients and more common in males, older age group, patients with higher Body Mass Index (BMI) and was associated with worse prognosis as compared to those with normal serum calcium levels. Mortality within 90 days of follow-up occurred in 42.86%, 20% and 6.25% in unstable angina and 39.29% 11.76% and 13.33% in AMI in hypocalcaemic, normocalcaemic and hypercalcaemic groups, respectively. It is inferred that 64% of the patients in hypocalcaemia tertile (n=14) were males in unstable angina and overwhelming 78.57% in AMI. Conclusion: Hypocalcaemia (corrected calcium <8.1 mg/dL) is common in patients of ACS and a predictor of adverse outcomes.