Prognostic value of exercise-induced pulmonary congestion by lung ultrasound in patients with heart failure

Introduction Pulmonary congestion during exercise is related to a poor prognosis in patients with heart failure (HF). B-Lines assessed by lung ultrasound quantitatively identify pulmonary congestion. The aim of this study was to evaluate the prognostic value of exercise-induced B-lines in patients with HF. Methods Patients with HF who were admitted to Okayama University Hospital between February 2021 to June 2024 were enrolled. Symptom-limited exercise echocardiography using a bicycle ergometer was performed at the time of discharge. B-lines were evaluated in the 2-site simplified scan. The end point was cardiac death or hospitalization for HF. Results A total of 124 patients with HF (71 [57–78] years, 65% male) were enrolled. The total number of B-lines was 1.9 ± 2.1 at rest, which significantly increased to 5.4 ± 3.5 at the peak workload of the average 40 W. In the receiver operating characteristic curve, the cut-off value of exercise-induced B-lines ≥7 at peak workload was related to cardiac events (sensitivity: 50%, specificity: 79%). During the follow-up period of 25 months, 26 patients had cardiac events. Kaplan–Meier analysis showed that the event-free survival rate was significantly worse in patients with B-lines ≥7 at peak workload than in those with B-lines <7 at peak workload (log-rank test, P = .002). B-lines ≥7 at peak workload were independently related to cardiac events. Conclusion Exercise-induced B-lines are associated with cardiac death or hospitalization for HF in patients with HF. B-lines at peak workload may identify risk stratification of HF.