Lung ultrasound in acute heart failure: association between quality of life, symptoms and B-lines
Authors: Lee M , Campbell R T , Claggett B L , Lewis E F , Groarke J D , Docherty K F , Lindner M , Liu J , Solomon S D , McMurray J J V , Platz E 
Published: October 2021

Abstract

Background
Impaired health-related quality of life (HRQL) and pulmonary congestion are common and important findings among patients hospitalized for acute heart failure (AHF). There are few data describing the association between HQRL, symptoms and pulmonary congestion in AHF.

Purpose
This study investigates whether worse HRQL and symptoms is associated with more pulmonary congestion. Pulmonary congestion measured by lung ultrasound (LUS) in patients with AHF is a marker of worse prognosis at baseline and pre-discharge.

Methods
In this 2-site, prospective, observational study, four-zone LUS was performed at baseline (LUS1) and within 72h of hospital discharge (LUS2) in patients hospitalized for AHF. B-lines were quantified off-line, blinded to clinical findings and outcomes, by a core laboratory. Clinicians managing the patients were blinded to LUS findings. HRQL was assessed at baseline using the patient-reported Kansas City Cardiomyopathy Questionnaire Total Symptom Score (KCCQ-TSS). Physician assessment of functional limitation at baseline was reported using the NYHA classification. In a subset of participants, patient-reported dyspnea at rest was also examined, at baseline and pre-discharge, using a numeric ranking scale (range 0–10; 10 worst). Dyspnea on exertion was also examined at baseline.

Results
Among 322 patients (mean age 72, 60% men, mean LVEF 39%) the median [interquartile range] KCCQ-TSS score was 33 [18–48]. Those with worse KCCQ-TSS scores, analyzed in tertiles, were younger, more likely to be obese and have diabetes mellitus and asthma/COPD, more likely to be on diuretics and report worse dyspnea at rest. At baseline, worse KCCQ-TSS was associated with worse NYHA class (Spearman's rho = −0.33, p&lt;0.0001), dyspnea at rest (Spearman's rho = −0.41, p&lt;0.0001) and dyspnea on exertion (Spearman's rho = −0.44, p&lt;0.0001). A higher number of B-lines on LUS1 was weakly associated with worse NYHA class (Spearman's rho = 0.15, p=0.007) (Figure 1) but was not significantly associated with KCCQ-TSS (p=0.91), dyspnea at rest (p=0.74) or dyspnea on exertion (p=0.96). Among 118 patients with LUS2 performed within 72h of hospital discharge, pre-discharge dyspnea at rest was not significantly associated with B-lines (p=0.98).

Conclusion
Among patients hospitalized for AHF, at baseline, worse KCCQ-TSS was associated with worse NYHA class, dyspnea at rest and dyspnea on exertion but was not significantly associated with pulmonary congestion assessed by LUS. A higher number of B-lines at baseline was associated with worse NYHA class. Patient-reported breathlessness and HQRL measures, although important, may not consistently reflect the degree of pulmonary congestion in patients with AHF.

Funding Acknowledgement
Type of funding sources: Public Institution(s). Main funding source(s): National Institutes of Health/National Heart, Lung, and Blood Institute (NIH/NHLBI) (K23HL123533 to E.P.) and the British Heart Foundation (PG/13/17/30050 to R.T.C. and J.J.V.M.) Association of LUS1 B-lines & NYHA class