Pivetta E, Goffi A, Lupia E, Tizzani M, Porrino G, Ferreri E, Volpicelli G, Balzaretti P, Banderali A, Iacobucci A, et al. Lung Ultrasound-Implemented Diagnosis of Acute Decompensated Heart Failure in the ED: A SIMEU Multicenter Study. Chest. 2015 Jul;148(1):202-210. doi: 10.1378/chest.14-2608.
The Idea: Acute decompensated heart failure is a common reason for ED presentation with acute dyspnea, and the tools to evaluate and categorize acute dyspnea as ADHF or noncardiogenic have not changed in many years. Lung ultrasound (LUS) is an emerging tool for diagnosis of pulmonary conditions, including evidence that LUS can be used for evaluation of ADHF because of the correlation of B-lines with pulmonary edema. However, there have been concerns about the accuracy of LUS for ADHF, and there is concern about the utility in differentiating cardiogenic and non-cardiogenic cause of acute dyspnea in emergent situations when treatment is often the same for both conditions. The objective of this study was to evaluate the use of lung ultrasound with clinical assessment in the diagnosis of acute decompensated heart failure in the ED.
The Study: This was a multicenter, observational, prospective cohort study that was done in 7 Italian emergency departments (both academic and community) using adult patients who presented with acute dyspnea from Oct 2010 to Sept 2012. EM physicians with expertise in lung ultrasound were asked to diagnose a patient with dyspnea with ADHF or noncardiogenic dyspnea first after the initial standard workup and then again after performing lung ultrasound. The curvilinear probe was used for all patients, and 3 zones were identified on each side of the chest (6 total). Lung ultrasound images were also reviewed by an independent expert afterwards, and a diagnosis of ADHF was defined as bilateral presence of 2+ zones with 3+ B-lines. All patients had a chest x-ray, and some had BNP levels measured. Blinded expert EM and cardiology physicians reviewed the patient’s chart after discharge and designated the final diagnosis of the cause of dyspnea (ADHF versus noncardiogenic).
Inclusion Criteria: Age > 18 presenting with acute dyspnea
Exclusion Criteria: Dyspnea obviously not due to acute decompensated heart failure (for example trauma), patient already with invasive ventilation when evaluated
The Results: 1,005 patients were enrolled in the study of 1,007 that were eligible. 2 patients declined to consent to enroll. The final diagnosis was ADHF for 46% of patients and noncardiogenic dyspnea for 54%. The sensitivity and specificity of the LUS-implemented (clinical assessment + LUS) were 97% and 97.4% respectively, which were both higher than clinical workup alone (85.3%, 90%). The net reclassification improvement (NRI) of the LUS-implemented approach compared to standard clinical workup was 19.1% with improvements in sensitivity and specificity by 11.7% and 7.4%. Additionally, LUS alone had higher sensitivity and sensitivity than chest radiography (90.5%, 93.5% versus 69.5%, 82.1%) and than BNP levels (89.3%, 89.8% versus 85%, 61.7%) in that subgroup. The subgroup that had BNP/NT-pro-BNP levels had 486 patients.
The Takeaway: Lung ultrasound in conjunction with clinical assessment can improve sensitivity, specificity, and diagnostic accuracy for ADHF in the emergency department when compared to standard clinical workup. Additionally, LUS alone is more accurate than chest radiography and BNP/NT-pro-BNP levels in the diagnosis of ADHF.
Mikayla Ambarian, MS4