Usefulness of lung ultrasound in the outpatient management of chronic heart failure patients: preliminary results of multicenter prospective randomized study

Abstract

Purpose: Ultrasound lung comets or B‐lines are a sonographic sign of extravascular lung water and lung ultrasound (LUS) has been proposed as a useful method to evaluate pulmonary congestion in patients with heart failure (HF). The aim of this study is to evaluate the clinical usefulness of LUS in addition to clinical examination in the outpatient management of chronic HF patients. Methods: This is a multicenter prospective randomized study. The planned sample size consists of 440 patients with chronic HF. The patients were randomized in 2 groups: group A, patients undergoing LUS; and group B, patients undergoing only physical examination. The diuretic therapy was modified according to the presence and severity of B‐lines in group A and physical examination in group B. The ultrasound examination was performed by a handheld echocardiography. The patients were evaluated at baseline and after 3 months of follow‐up. The inclusion criteria were: (1) History of HF for at least 6 months, (2) Left ventricular ejection fraction < 45% measured by echocardiography, (3) Adequate medical therapy for HF for at least 2 months. The primary end‐point was a significant reduction of hospitalizations for acute decompensated heart failure (ADHF) in group A during follow‐up period. The secondary end‐points were the changes of NT‐proBNP values and QLT score and cardiac mortality. Results: To date, we enrolled 92 patients (mean age 75.4±10 years, 65 males), 50 in group A and 42 in group B. The hospitalization rate for ADHF after 3 months was 6.0% in group A and 21.4% in group B (OR: 0.23, 95% CI: 0.06‐0.9; p=0.03). In group A, the mean values of NT‐proBNP did not differ significantly between baseline and at 3 months (1825±322 pg/ml vs 1667.8±313 pg/ml, p=0.2), while in group B there was an increase (1941.3±303 pg/ml vs 2642.2±684 pg/ml, p=0.14). The mean QLT scores in group A were 14.2±1.3 at baseline and 13.1±1.2 at 3 months (p=0.004), while in group B the mean scores were 14.5±1.1 and 16.2±1.1 (p=0.006). The mortality rate at 3 months was 4.0% in group A and 0% in group B (OR: 1.0, 95% CI: 0.98‐1.1; p=0.2). The NYHA class in group A was 2.4±0.5 at baseline and 2.3±0.4 at 3 months (p=0.05) and 2.4±0.5 vs 2.5±0.6 in group B (p=0.16). Conclusions: The identification of B‐lines by LUS could be a useful tool in addition to physical examination for the outpatient management of chronic HF patients. This approach could lead to the optimization of diuretic therapy, and consequently reduce the rate of hospitalizations for ADHF.