Lung Ultrasound in Acute Heart Failure: Prevalence of Pulmonary Congestion and Short- and Long-Term Outcomes

Abstract

ObjectivesThis study sought to assess the prevalence, changes in, and prognostic importance of B-lines, a pulmonary congestion measure by using a simplified lung ultrasonography (LUS) method in acute heart failure (AHF). BackgroundPulmonary congestion is an important finding in AHF, but conventional methods for its detection are insensitive. MethodsIn a 2-site, prospective, observational study, 4-zone LUS was performed early during hospitalization for AHF (LUS1) and at discharge (LUS2). B-lines were quantified off-line, blinded to clinical findings and outcomes, by a core laboratory. ResultsAmong 349 patients (median, 75 years of age; 59% men; mean ejection fraction 39%), the sum of B-lines in 4 zones ranged from 0 to 18 (LUS1). The risk of an adverse in-hospital event increased with rising number of B-lines on LUS1: the odds ratio for each B-line tertile was 1.82 (95% confidence interval [CI]: 1.14 to 2.88; p = 0.011). B-line count decreased from a median of 6 (LUS1) to 4 (LUS2; p < 0.001) over 6 days (median). In 132 patients with LUS2 images, the risk of HF hospitalization or all-cause death was greater in patients with a higher number of B-lines at discharge. This relationship was stronger closer to discharge: unadjusted hazard ratio (HR) at 60 days was 3.30 (95% CI: 1.52 to 7.17; p = 0.002); 2.94 at 90 days (95% CI: 1.46 to 5.93; p = 0.003); and 2.01 at 180 days (95% CI: 1.11 to 3.64; p = 0.021). The association between number of B-lines and short- and long-term outcomes persisted after adjusting for important clinical variables, including N-terminal pro–B-type natriuretic peptide. ConclusionsPulmonary congestion using a simplified 4-zone LUS method was common in patients with AHF and improved with therapy. A higher number of B-lines at baseline and discharge identified patients at increased risk for adverse events.