Point-of-care ultrasound modalities in terms of diagnosing acute decompensated heart failure in emergency department; a diagnostic accuracy study

This study aimed to compare the diagnostic accuracy of heart, lung and inferior vena cava (IVC) ultrasonography modalities, alone and combined, for possible added accuracy in diagnosing acute decompensated heart failure (ADHF), in a group of patients with the final diagnosis of ADHF based on plasma level of B-type natriuretic peptide (BNP) as the standard. The present study is a diagnostic accuracy study, which was carried out in the emergency department of Imam Khomeini hospital, affiliated to Tehran University of Medical Sciences, in 2014–2015. All patients over 18 years old, who were referred to emergency department with complaint of acute dyspnea were regarded as eligible and no exclusion criteria were considered. All ultrasounds were performed by a trained emergency medicine resident and then saved and classified for each patient, separately, and reviewed by the attending emergency medicine physician. In this study, patients with BNP levels higher than 500 pg/ml were considered positive for dyspnea caused by heart failure. A total of 120 patients with an average age of 60.83 ± 16.528 years were studied, 64 (53%) of which were male. In total, 47.5% of patients had a BNP level over 500 pg/ml. Among patients with positive ultrasound, 94.7% were true positive and among those with a negative ultrasound, 61.4% were true negative. Based on the findings, B-line ≥ 10 has the highest specificity and left ventricular ejection fraction (LVEF) < 45% has the highest sensitivity. The combination of LVEF and IVC collapsibility index (IVC-CI), LVEF and BLC, IVC-CI and BLC, and IVC-CI and BBPC had a higher specificity rate and combination of LVEF and BBPC and BLC and BBPC had the highest sensitivity. Sensitivity, specificity, positive predictive value and negative predictive value of all three ultrasounds combined were 31.6%, 98.4%, 94.7% and 61.4%, respectively. In this study, the diagnostic accuracy of double and triple ultrasonography of heart, lung and IVC in the diagnosis of ADHF was very high, among which triple ultrasonography was more preferable.