Use of Lung Ultrasound For Diagnosing Acute Heart Failure in Emergency Department of Southern India.

INTRODUCTION: Diagnosing heart failure is often a challenge for the healthcare providers due to it's non-specific and usually subtle physical presentations. The outcomes for treatment are strongly related to the stage of the disease. Considering the importance of early and accurate diagnosis, it is important to have an easy, inexpensive, non-invasive, reliable and reproducible method for diagnosis of heart failure. Recent advancement in radiology and cardiology are supporting the emerging technique of lung ultrasound through B-line evaluation for identifying extravascular lung water.

AIM: To establish lung ultrasound as an easy, inexpensive, non-invasive, reliable and reproducible method for diagnosing Acute Decompensated Heart Failure (ADHF) in emergency department.

MATERIALS AND METHODS: The study was a cross-sectional, prospective, observational, diagnostic validation study of lung ultrasound for diagnosis of acute heart failure in an emergency department and was performed at Amrita Institute of Medical Science, Kochi, Kerala, India. A total of 42 patients presenting with symptoms suggestive of acute decompensated heart failure were evaluated by plasma B-type Natriuretic Peptide (BNP), Echocardiography (ECHO) and X-ray. Lung ultrasound was done to look for the presence of B-lines.

STATISTICAL ANALYSIS: Sensitivity, specificity and predictive value of diagnostic modalities were calculated using Mc Nemar's Chi-square test for the presence and absence of heart failure.

RESULTS: Lung ultrasound showed a sensitivity of 91.9% and a specificity of 100% in diagnosing acute heart failure comparable to plasma BNP which had a sensitivity of 100% and a specificity of 60%. It was also superior to other methods of diagnosing ADHF namely X-ray and ECHO and showed a good association.

CONCLUSION: Lung ultrasound and its use to detect ultrasonographic B-lines is an early, sensitive and an equally accurate predictor of ADHF in the emergency setting as compared to BNP.