Comparison between the Levels of N Terminal Pro-Brain Natriuretic Peptide and Troponin I to Predict Left Ventricular Ejection Fraction in Patients Presenting with First ST-Elevation Myocardial Infarction

Objectives: To compare the levels of N Terminal- ProBrain natriuretic peptide (NT-proBNP) and Troponin I (Trop I) to predict left ventricular ejection fraction (LVEF) in patients presenting with first ST-elevation myocardial infarction (STEMI). Methodology: A cross-sectional study was carried out in Cardiology department of a tertiary care hospital from June to November 2021. A total of 150 patients who presented at emergency department with first STEMI and underwent primary percutaneous coronary intervention (PCI) were included. The patient’s second set of troponin I and NT-proBNP were collected during hospitalization. Echocardiography was done. Left ventricular function was assessed using modified Simpson’s method. For data analysis, SPSS 21 was used. Results: The mean age was 60.60±11.1 years. There were 76% males, 53% hypertensive, 44% diabetic, 14% smokers with the most prominent type of myocardial infarction being anterior wall myocardial infarction accounting for 76.7%. Mean Trop I was 12.2±6.81 ng/ml, 9.5±8.63 ng/ml and 3.0±5.41 ng/ml for LVEF≤40%, 41-49% and >50% respectively while NT-proBNP was 7136.4±7.97pmol/l, 2328.9±3498.6pmol/l and 441±283.6pmol/l for LVEF ≤40%, 41-49%, and >50% respectively. We found a significant mean difference for Trop I (p=0.000) and NT-proBNP (p=0.0001). There was an inverse significant relationship of left ventricular ejection fraction with Trop I (r=-0.290, p=0.000) and NT- proBNP (r=-0.388, p=0.000). Conclusion: In comparison to Troponin I, NT-proBNP serves as a better marker to predict LVEF in patients presenting with first STEMI.