Does body mass index influence the number of B-lines on lung ultrasonography compared to NT-proBNP levels in patients with heart failure?
Lung ultrasonography remains a useful tool for assessing pulmonary congestion in heart failure patients with obesity, as B-lines are less attenuated by increasing BMI compared to NT-proBNP levels.
AIMS: Increased body mass index (BMI) is common in heart failure (HF) patients and is associated with lower levels of N-terminal pro-brain natriuretic peptide (NT-proBNP). We evaluated the influence of BMI on lung ultrasonography (LUS) findings indicative of pulmonary congestion (i.e. B-lines) in patients with chronic and acute HF (AHF). METHODS AND RESULTS: , mean ejection fraction 42%) undergoing echocardiography and LUS in eight chest zones. B-lines and chest wall thickness (skin to pleura) on ultrasound were quantified offline and blinded to clinical findings. NT-proBNP was available in AHF patients (n = 167). In chronic HF, B-line number decreased by 18% per 5 unit increase in BMI 95% confidence interval (CI) -35% to +5%, P = 0.11. In AHF, the number of B-lines decreased by 12% per 5 unit increase in BMI (95% CI -19% to -5%, P = 0.001), whereas NT-proBNP concentration decreased by 28% per 5 unit increase in BMI (95% CI -40% to -16%, P 6 B-lines were observed in half of AHF patients with severe obesity. There was an inverse relationship between B-line number and chest wall thickness, and this association varied by chest region. CONCLUSIONS: Despite an inverse relationship between B-lines and BMI, B-lines declined to a lesser degree than NT-proBNP with increasing BMI. These data suggest that LUS may be useful in patients with HF despite obesity.
Brainin et al. (Thu,) studied this question.