N-Terminal Pro-Brain Natriuretic Peptide Levels in Patients Presenting with Acute Breathlessness in Emergency Department

Abstract

Introduction: Breathlessness is one of the most common symptoms in patients presenting to the emergency department. Differentiating Congestive Heart Failure (CHF) from other causes of dyspnea is of extreme importance. N-Terminal pro-Brain Natriuretic Peptide (NT-proBNP) levels may be valuable for the diagnosis of Heart Failure (HF) in patients with acute breathlessness when used in combination with other clinical information. Aim: To find the utility of NT-proBNP levels in patients presenting with acute breathlessness. Materials and Methods: This cross-sectional study was conducted on 255 patients presenting with acute breathlessness. Details of clinical history, clinical examination, laboratory tests, Electrocardiogram (ECG), X-ray chest, and 2D echocardiogram were collected from each patient. A 5 mL sample of peripheral venous blood was taken from the patients for the quantitative determination of NT-proBNP levels. Mann-Whitney U test was used to compare medians of continuous variables. Sensitivity, specificity, Positive Predictive Value (PPV), Negative Predictive Value (NPV) and accuracy were determined for NT-proBNP levels. Results: The mean age of the patients was 58.9 years. The median NT-proBNP level was significantly higher in patients who had HF compared to respiratory failure and Hyperventilation Syndrome (HVS). The sensitivity and specificity of NT-proBNP level >450 pg/mL was 76.9% and 90.0%, respectively for patients <50 years of age. The sensitivity and specificity of NT-proBNP level >900 pg/mL was 82.9% and 92.3%, respectively for patients 50-75 years of age. The sensitivity and specificity of NT-proBNP level >1800 pg/mL was 61.5% and 100.0%, respectively for patients >75 years of age. Conclusion: NT-proBNP measurement is a useful biochemical tool for the emergency room physician in the rapid and reliable diagnosis of HF in patients with acute breathlessness.