Prognostic Value of Lung Ultrasound in Ambulatory Patients with Recently Diagnosed Heart Failure with Preserved Ejection Fraction
DOI:
https://doi.org/10.64149/J.Ver.8.3.21-30Keywords:
HFpEF; lung ultrasound; B-lines; pulmonary congestion; NT-proBNP; prognosis; risk stratificationAbstract
Background: Heart failure with preserved ejection fraction (HFpEF) is highly prevalent and clinically diverse, with pulmonary congestion (PC) playing a central role in driving poor outcomes. Lung ultrasound (LUS) allows bedside detection of PC through B-line quantification, but its prognostic role in ambulatory HFpEF has not been fully established.
Objective: to compare the prognostic utility of LUS-derived B-lines with N-terminal pro-B-type natriuretic peptide (NT-proBNP) and echocardiographic measures, particularly left atrial reservoir strain (LASr), in patients recently diagnosed with HFpEF in the outpatient setting.
Methods: A total of 131 consecutive patients with suspected HFpEF underwent comprehensive echocardiography, LUS using a 28-zone protocol, and NT-proBNP testing. Following exclusion based on predefined criteria, 75 patients (mean age 70.3 ± 6.7 years; 56.0% women) were enrolled and monitored for a composite endpoint of heart failure hospitalization, diuretic intensification, or all-cause mortality over a median follow-up of 26 [22–32] months.
Results: Eleven patients (14.7%) experienced the composite outcome during follow-up. LUS was feasible in all patients, requiring 2.5 ± 0.47 minutes per scan. B-line counts correlated positively with NT-proBNP (r = 0.330, p<0.001) and inversely with LASr (r = –0.418, p<0.001). A threshold of >15 B-lines showed strong prognostic accuracy (AUC 0.863, 95% CI: 0.771–0.955), comparable to NT-proBNP (AUC 0.859, 95% CI: 0.765–0.952; p=0.927). Multivariable analysis confirmed >15 B-lines (HR 15.234, 95% CI: 1.864–124.530, p=0.011) and log-transformed NT-proBNP (HR 2.876, 95% CI: 1.187–6.967, p=0.019) as independent predictors. Event-free survival at 20 and 40 months was 100% and 97.3% in patients with ≤15 B-lines, compared to 72.0% and 58.2% in those with >15 (log-rank χ²=16.804, p<0.001).
Conclusions: LUS B-line quantification is a rapid, feasible, and reliable method for prognostic assessment in ambulatory HFpEF. A threshold of >15 B-lines identifies patients at higher risk of adverse events, with performance comparable to NT-proBNP, supporting its role in risk stratification and potential integration into outpatient management.
