Ultrasound B-lines Research Articles

Incidence of Acute Pulmonary Edema Before and After the Systematic Use of Ultrasound B-Lines

Introduction: Acute pulmonary edema (APE) due to fluid overload is considered the most feared complication in hemodialysis patients. Various diagnostic tests have been proposed to assess the fluid status in patients with end-stage kidney failure (ESKF); among these, lung ultrasound (measuring the number of B-lines) is emerging as a promising tool to identify pulmonary congestion in this patient population. Methods: We compared the incidence of APE before and after the implementation of lung ultrasound as a routine practice in our unit. The pre (from 1 January 2007 to 31 December 2008)- and post (from 1 January 2017 to 31 December 2018)-B-line implementation periods included 98 and 108 hemodialysis patients, respectively. By accurately reviewing their electronic medical records, all episodes of APE were collected. The 10-year interval between the two periods was specifically chosen to ensure no overlap between patients of the two cohorts whereas the single-center design was adopted to minimize the influence of center effect on the study results. Results: APE episodes occurred more frequently in patients from the pre-B-line implementation group (18/98, i.e., 18.4%) compared with those from the post B-line implementation group (6/108, i.e., 5.5%) (p = 0.004). An analysis based on repeated APE events showed that the incidence rate of APE was significantly higher during the pre-implementation period (2.0 APE episodes per 100 person-months, 95% CI: 1.4–2.7) than during the post-implementation period (0.3 APE episodes per 100 person-months, 95% CI: 0.1–0.7), with an incidence rate ratio (post- versus pre-) of 0.17 (95% CI: 0.07–0.40; p < 0.001). The odds of experiencing APE episodes were 74% lower (odds ratio: 0.26, 95% CI: 0.10–0.69) in patients from the post B-line implementation period compared with those from the pre-implementation period. Notably, adjusting for potential confounders did not affect the strength of this association, which remained statistically significant (p ≤ 0.030). Finally, dominance analysis indicated that the implementation of B-lines was the primary factor explaining the difference in APE episodes between the two periods, followed by dialysis duration and intra-dialysis weight gain. Conclusions: The systematic use of lung ultrasound (a simple, easy-to-learn, rapid and non-invasive method, easily performed at the patient’s bed) in everyday clinical practice was associated with a drastic reduction in episodes of APE in hemodialysis patients. Further observational and interventional studies are needed to confirm these results.

Multiparametric assessment of decongestion in patients admitted with acute heart failure: dynamic changes and correlation with natriuresis

Abstract Background Heart Failure (HF) is a major public health problem, expected to increase in the next few decades. The vast majority of acute HF (AHF) episodes are precipitated by congestion with volume overload and/or fluid redistribution. Current Guidelines stress on the importance of relieving congestion before discharge, recommending anyway only daily assessment of signs and symptoms. Lung ultrasound (LUS) B-lines and other ultrasound markers of congestion has emerged as valuable tools to improve diagnostic accuracy and help clinicians in fluid management. Purpose To assess the dynamic changes of B-lines and other markers of congestion and their relationship with the clinical evaluation, chest X-ray (CXR) and natriuretic peptides in patients admitted for AHF. Methods Fifty-eight patients (age 72±11 ys, 35% women) admitted with acute HF were enrolled. Patients underwent clinical evaluation (Clinical Congestion Score, CCS, including rales, pathological S3 heart sound, pedal oedema, jugular vein distension; range 0-4), and CXR (CXR score, including enlargement and loss of definition of hilar structures, peribronchial and perivascular cuffing, cardiomegaly, pleural effusion; range 0-4). An integrated multiorgan ultrasound exam including LUS B-lines, echocardiography, and venous excess ultrasound (VExUS) score was performed at admission (T0), between 24 and 48 hours from T0 (T1), and at discharge (T2). Follow-up data at 30 days were collected. Results Mean CCS was 1.52±0.99 at T0, with a reduction at T1 (0.86±0.66; p<0.01), and at T2 (0.34±0.66; p<0.01). Sixteen percent of patients with a CCS=0 at T0 showed, however, persistent B-lines on LUS (mean B-lines 19±6). The mean number of B-lines was 26±12 at T0 with a reduction at T1 (17±11; p<0.001), and at T2 (13±11; p<0.001). Other echocardiographic non-invasive hemodynamic parameters, such as pulmonary artery systolic pressure (PASP) and E/e’ showed a reduction only at T2, but not at T1 (figure). The number of B-lines correlated at all time points with CCS, CXR score, VExUS score, and NT-proBNP values (all p<0.05). We divided patients into two groups: "responders" (with ≥15 reduction of B-lines between T0 and T2) and "non-responders" (with <15 reduction of B-lines between T0 and T2). Responders had higher chlorine and sodium urinary excretion at T1 compared to non-responders. The number of B-lines at all time points was associated to 30-days cardiovascular mortality at univariable analysis. Neither CCS nor CXR score were associated with 30-day events. Conclusions In patients with acute HF, B-lines quantification is related to standard congestion assessment based on clinical evaluation, CXR and NT-proBNP, showing, however, a more dynamic behaviour in the assessment of decongestion. B-lines variations are also related to diuresis and chlorine urinary output, a recognized predictor of diuretic response. Persistent congestion is related to an increased risk of hospitalization and death.

May right heart failure cause pulmonary congestion in pulmonary arterial hypertension?

Abstract Aims Recent studies have shown that lung ultrasound-assessed pulmonary congestion is worse in heart failure when pulmonary vascular resistance (PVR) is increased, suggesting a paradoxical relationship between right heart failure and increased lung water content. Accordingly, we wondered if lung ultrasound would reveal otherwise clinically silent pulmonary congestion in patients with pulmonary arterial hypertension (PAH). Methods and results All patients referred for suspicion of PAH in a tertiary center from January 2020 to December 2022 underwent a complete diagnostic work-up including echocardiography, lung ultrasound and right heart catheterization. Pulmonary congestion was identified by lung ultrasound B-lines using an 8-site scan. The study enrolled 102 patients with idiopathic PAH (mean age 53±13; 71% female). WHO functional classes I, II and III were found respectively in 2, 52 and 46% of them. The N-terminal-pro-brain natriuretic peptide (NT-proBNP) was 377 pg/mL [interquartile range, IQR 218, 906]. B-lines were identified in 77 out of 102 patients (75%), with a median of 3 [IQR: 1-5]. At univariable analysis B-lines were positively correlated to male sex, age, NT-proBNP, systolic PA pressure (sPAP), right atrial pressure (RAP), PVR, left ventricular end-diastolic volume and tricuspid annulus plane systolic excursion (TAPSE), and negatively to cardiac output and stroke volume. At multivariable analysis, RAP (p<0.001; Fig 1), TAPSE/sPAP (p=0.001), and NT-proBNP (p=0.04) were independent predictors of B-lines. Conclusion Lung ultrasound commonly discloses pulmonary congestion in PAH. This finding is related to right ventricle to pulmonary artery uncoupling, and may tentatively be explained by increased central venous pressure impeding lymphatic outflow.Figure 1

Active learning based on multi-enhanced views for classification of multiple patterns in lung ultrasound images

There are several main patterns in lung ultrasound (LUS) images, including A-lines, B-lines, consolidation and pleural effusion. LUS images of healthy lungs typically only exhibit A-lines, while other patterns may emerge or coexist in LUS images associated with different lung diseases. The accurate categorization of these primary patterns is pivotal for effective lung disease screening. However, two challenges complicate the classification task: the first is the inherent blurring of feature differences between main patterns due to ultrasound imaging properties; and the second is the potential coexistence of multiple patterns in a single case, with only the most dominant pattern being clinically annotated. To address these challenges, we propose the active learning based on multi-enhanced views (MEVAL) method to achieve more precise pattern classification in LUS. To accentuate feature differences between multiple patterns, we introduce a feature enhancement module by applying vertical linear fitting and k-means clustering. The multi-enhanced views are then employed in parallel with the original images, thus enhancing MEVAL’s awareness of feature differences between multiple patterns. To tackle the patterns coexistence issue, we propose an active learning strategy based on confidence sets and misclassified sets. This strategy enables the network to simultaneously recognize multiple patterns by selectively labeling of a small number of images. Our dataset comprises 5075 LUS images, with approximately 4% exhibiting multiple patterns. Experimental results showcase the effectiveness of the proposed method in the classification task, with accuracy of 98.72%, AUC of 0.9989, sensitivity of 98.76%, and specificity of 98.16%, which outperforms than the state-of-the-art deep learning-based methods. A series of comprehensive ablation studies suggest the effectiveness of each proposed component and show great potential in clinical application.

Impact of staged goal-directed fluid therapy on postoperative pulmonary complications in patients undergoing McKeown esophagectomy: a randomized controlled trial

BackgroundOur aim was to evaluate the influence of staged goal directed therapy (GDT) on postoperative pulmonary complications (PPCs), intraoperative hemodynamics and oxygenation in patients undergoing Mckeown esophagectomy.MethodsPatients were randomly divided into three groups, staged GDT group (group A, n = 56): stroke volume variation (SVV) was set at 8–10% during the one lung ventilation (OLV) stage and 8–12% during the two lung ventilation (TLV) stage, GDT group (group B, n = 56): received GDT with a target SVV of 8–12% During the entire surgical procedure, and control group (group C, n = 56): conventional fluid therapy was administered by mean arterial pressure (MAP), central venous pressure (CVP), and urine volume. The primary outcome was the incidence of postoperative pulmonary complications within Postoperative days (POD) 7. The secondary outcomes were postoperative lung ultrasound (LUS) B-lines artefacts (BLA) scoring, incidence of other complications, the length of hospital stay, intraoperative hemodynamic and oxygenation indicators included mean arterial pressure (MAP), heart rate (HR), cardiac index (CI), cardiac output (CO), oxygenation index (OI), respiratory indices (RI), alveolar-arterial oxygen difference (Aa-DO2).ResultsPatients in group A and group B had a lower incidence of PPCs (7/56 vs. 17/56 and 9/56 vs. 17/56, p < 0.05), and a fewer B-lines score on postoperative ultrasound (4.61 ± 0.51 vs. 6.15 ± 0.74 and 4.75 ± 0.62 vs. 6.15 ± 0.74, p < 0.05) compared to group C. The CI, CO, MAP, and OI were higher in group A compared to group B and group C in the stage of thoracic operation. During the abdominal operation stage, patients in group A and group B had a better hemodynamic and oxygenation indicators than group C.ConclusionsIn comparison to conventional fluid therapy, intraoperative staged GDT can significantly reduce the incidence of postoperative pulmonary complications in patients undergoing McKeown esophagectomy, facilitating patient recovery. Compared to GDT, it can improve intraoperative oxygenation and stabilize intraoperative hemodynamics in patients.Trial registrationThis study was registered in the Chinese Clinical Trial Registry on 24/11/2021 (ChiCTR2100053598).

Efficacy and safety of hypertonic saline therapy in ambulatory patients with heart failure: The SALT-HF trial.

Combination of hypertonic saline solution (HSS) with intravenous loop diuretics has been suggested to improve diuretic response in patients hospitalized for heart failure (HF). The efficacy and safety of this approach in the ambulatory setting remain unexplored. In this multicentre, double-blind, randomized study, we allocated ambulatory patients with worsening heart failure (WHF) to a 1-h infusion of intravenous furosemide (ivFurosemide)-HSS versus ivFurosemide. The primary endpoint was the volume of diuresis at 3 h. Secondary endpoints included 3-h natriuresis and weight variation, 7-day congestion data, kidney function and electrolytes, and 30-day clinical events. Overall, 167 participants (median age: 81 years, 30.5% female) were randomized across 13 sites between December 2020 and March 2023. There were no differences in 3-h diuresis between treatments (ivFurosemide-HSS: 1099 ml vs. ivFurosemide: 1103 ml, p = 0.963), 3-h natriuresis (∆ +2.642 mEq/L, p = 0.559), or 3-h weight (∆ +0.012 kg, p = 0.920). Patients in the ivFurosemide-HSS arm experienced significant weight decrease at 7 days (Δ -0.586 kg, p = 0.048). There were no between-treatment differences in clinical congestion score, biomarkers, inferior vena cava diameter, or the presence of lung ultrasound B-lines. At 30 days, 26.5% of the patients in the ivFurosemide-HSS group versus 33.3% in the ivFurosemide group experienced WHF (hazard ratio 0.76, p = 0.330). The incidence of death from any cause or HF hospitalization was 6% of patients in the ivFurosemide-HSS group and 8.3% of patients in the ivFurosemide group (hazard ratio 0.69, p = 0.521). The incidence of worsening kidney function or metabolic derangements was not significantly different in the two arms. A single infusion of ivFurosemide-HSS did not improve 3-h diuresis or congestion parameters in patients with ambulatory WHF. This therapy showed an appropriate safety profile.

Comparison of Lung Ultrasound B-Lines and Pleural Line Alterations with Automated Quantitative CT: Is it Possible to Overcome the Limitations of the Ultrasound Method?

Comparison of Lung Ultrasound B-Lines and Pleural Line Alterations with Automated Quantitative CT: Is it Possible to Overcome the Limitations of the Ultrasound Method?

Cardiovascular effects of breath-hold diving at altitude

ABSTRACT Marabotti C, Laurino M, Passera M, Cialoni D, Franzino E, Benvenuti C, Pingitore A. Cardiovascular effects of breath-hold diving at altitude. Undersea Hyperb Med. 2024 Second Quarter; 51(2):189- 196. Hypoxia, centralization of blood in pulmonary vessels, and increased cardiac output during physical exertion are the pathogenetic pathways of acute pulmonary edema observed during exposure to extraordinary environments. This study aimed to evaluate the effects of breath-hold diving at altitude, which exposes simultaneously to several of the stimuli mentioned above. To this aim, 11 healthy male experienced divers (age 18-52y) were evaluated (by Doppler echocardiography, lung echography to evaluate ultrasound lung B-lines (BL), hemoglobin saturation, arterial blood pressure, fractional NO (Nitrous Oxide) exhalation in basal condition (altitude 300m asl), at altitude (2507m asl) and after breath-hold diving at altitude. A significant increase in E/e’ ratio (a Doppler-echocardiographic index of left atrial pressure) was observed at altitude, with no further change after the diving session. The number of BL significantly increased after diving at altitude as compared to basal conditions. Finally, fractional exhaled nitrous oxide was significantly reduced by altitude; no further change was observed after diving. Our results suggest that exposure to hypoxia may increase left ventricular filling pressure and, in turn, pulmonary capillary pressure. Breath-hold diving at altitude may contribute to interstitial edema (as evaluated by BL score), possibly because of physical efforts made during a diving session. The reduction of exhaled nitrous oxide at altitude confirms previous reports of nitrous oxide reduction after repeated exposure to hypoxic stimuli. This finding should be further investigated since reduced nitrous oxide production in hypoxic conditions has been reported in subjects prone to high-altitude pulmonary edema.

#1478 Effect of low vs standard dialysate sodium on 48-h ambulatory blood pressure in patients with intradialytic hypertension: a randomized crossover study

Abstract Background and Aims Intradialytic hypertension (IDH) is associated with increased risk for cardiovascular events and mortality. Patients with IDH exhibit higher 48-h blood pressure (BP) levels than patients without this condition. Volume and sodium excess are considered a major factor contributing in the development of this phenomenon. This study evaluated the effect of low (137 mEq/L) compared to standard (140 mEq/L) dialysate sodium concentration on 48-h BP in patients with IDH. Method In this randomized, single-blind, crossover study, 29 patients with IDH underwent 4 hemodialysis sessions with low (137 mEq/L) followed by 4 sessions with standard (140 mEq/L) dialysate sodium or vice-versa. Mean 48-h BP, pre-/post-dialysis and intradialytic BP, pre-dialysis weight, interdialytic weight gain (IDWG) and lung ultrasound B-lines were assessed. Results Mean 48-h SBP/DBP were significantly lower with low compared to standard dialysate sodium concentration (137.6 ± 17.0/81.4 ± 13.7 mmHg with low vs 142.9 ± 14.5/84.0 ± 13.9 mmHg with standard dialysate sodium, p = 0.005/p = 0.007 respectively); SBP/DBP levels were also significantly lower during the 44-h and different 24-h periods. Low dialysate sodium significantly reduced post-dialysis (SBP/DBP: 150.3 ± 22.3/91.2 ± 15.1 mmHg with low vs 166.6 ± 17.3/94.5 ± 14.9 mmHg with standard dialysate sodium, p &amp;lt; 0.001/p = 0.134 respectively) and intradialytic (141.4 ± 18.0/85.0 ± 13.4 mmHg with low vs 147.5 ± 13.6/88.1 ± 12.5 mmHg with standard dialysate sodium, p = 0.034/p = 0.013, respectively) BP compared with standard dialysate sodium. Pre-dialysis weight, IDWG and pre-dialysis B-lines were also significantly decreased with low dialysate sodium. Conclusion Low dialysate sodium concentration significantly reduced 48-h ambulatory BP compared with standard dialysate sodium in patients with IDH. These findings support low dialysate sodium as a major non-pharmacologic approach for BP management in patients with IDH. Registered at ClinicalTrials.gov with study number NCT05430438.

Risk prediction modelling in idiopathic inflammatory myositis-associated interstitial lung disease based on seven factors including serum KL-6 and lung ultrasound B-lines.

To develop a user-friendly nomogram-based predictive model for interstitial lung disease (ILD) in patients with idiopathic inflammatory myositis (IIM). A retrospective study was conducted at Shantou Central Hospital, encompassing 205 IIM patients diagnosed between January 2013 and December 2022. We used the LASSO regression method in the discovery set to select features for model construction, followed by efficacy verification through AUC of ROC. Afterwards, KL-6 values and LUS B-lines number were added into this model to evaluate whether these 2 factors added to the model efficiency. Finally, a web version was constructed to make it more available. Among the 205 IIM patients, 115 (56.1%) patients were diagnosed with ILD, and 90 (43.9%) did not. The predictive model, derived from the training set, comprised four independent risk factors, including age, presence of respiratory symptoms, anti-melanoma differentiation-associated gene 5 (MDA-5) antibody positivity, and anti-aminoacyl transfer RNA synthetase (anti-ARS) antibodies positivity. Notably, anti-TIF1-γ antibody positivity emerged as a protective factor. The AUC of the ROC based on these 5 factors was 0.876 in the training set and 0.861 in the validation set. The AUC of the ROC based on the 5 factors plus KL-6 was 0.922, 5 factors plus B-line number was 0.949 and 5 factors plus both KL-6 and B-line number was 0.951. Accordingly, a nomogram and a web version were developed. This predictive model demonstrates robust capability to assess ILD risk in IIM patients, particularly when augmented with serum KL-6 level or/and LUS B-line number.

Measuring congestion with a non-invasive monitoring device in heart failure and haemodialysis: CONGEST-HF.

We examined the effectiveness of a novel cardiopulmonary management wearable sensor (worn for less than 5 mins) at measuring congestion and correlated the device findings with established clinical measures of congestion. We enrolled three cohorts of patients: (1) patients with heart failure (HF) receiving intravenous diuretics in hospital; (2) patients established on haemodialysis, and (3) HF patients undergoing right heart catheterization (RHC). The primary outcomes in the respective cohorts were a Spearman correlation between (1) change in weight and change in thoracic impedance (TI) (from enrolment, 24 h after admission to discharge) in patients hospitalized for HF; (2) lung ultrasound B-lines and volume removed during dialysis with device measured TI, and (3) pulmonary capillary wedge pressure (PCWP) and sub-acoustic diastolic, third heart sound (S3) in the patients undergoing RHC. A total of 66 patients were enrolled. In HF patients (n = 25), change in weight was correlated with both change in device TI (Spearman correlation [rsp] = -0.64, p = 0.002) and change in device S3 (rsp = -0.53, p = 0.014). In the haemodialysis cohort (n = 21), B-lines and TI were strongly correlated before (rsp = -0.71, p < 0.001) and after (rsp = -0.77, p < 0.001) dialysis. Volume of fluid removed by dialysis was correlated with change in device TI (rsp = 0.49, p = 0.024). In the RHC cohort (n = 20), PCWP measured at one time point and device S3 were not significantly correlated (rsp = 0.230, p = 0.204). There were no device-related adverse events. A non-invasive device was able to detect changes in congestion in patients with HF receiving decongestion therapy and patients having fluid removed at haemodialysis. The cardiopulmonary management device, which measures multiple parameters, is a potentially useful tool to monitor patients with HF to prevent hospitalizations.

Low dialysate sodium and 48-h ambulatory blood pressure in patients with intradialytic hypertension: a randomized crossover study.

Intradialytic hypertension (IDH) is associated with increased risk for cardiovascular events and mortality. Patients with IDH exhibit higher 48-h blood pressure (BP) levels than patients without this condition. Volume and sodium excess are considered a major factor contributing in the development of this phenomenon. This study evaluated the effect of low (137mEq/L) compared with standard (140mEq/L) dialysate sodium concentration on 48-h BP in patients with IDH. In this randomized, single-blind, crossover study, 29 patients with IDH underwent four hemodialysis sessions with low (137mEq/L) followed by four sessions with standard (140mEq/L) dialysate sodium, or vice versa. Mean 48-h BP, pre-/post-dialysis and intradialytic BP, pre-dialysis weight, interdialytic weight gain (IDWG) and lung ultrasound B-lines were assessed. Mean 48-h systolic/diastolic BP (SBP/DBP) were significantly lower with low compared with standard dialysate sodium concentration (137.6±17.0/81.4±13.7mmHg with low vs 142.9±14.5/84.0±13.9mmHg with standard dialysate sodium, P=.005/P=.007, respectively); SBP/DBP levels were also significantly lower during the 44-h and different 24-h periods. Low dialysate sodium significantly reduced post-dialysis (SBP/DBP: 150.3±22.3/91.2±15.1mmHg with low vs 166.6±17.3/94.5±14.9mmHg with standard dialysate sodium, P<.001/P=.134, respectively) and intradialytic (141.4±18.0/85.0±13.4mmHg with low vs 147.5±13.6/88.1±12.5mmHg with standard dialysate sodium, P=.034/P=.013, respectively) BP compared with standard dialysate sodium. Pre-dialysis weight, IDWG and pre-dialysis B lines were also significantly decreased with low dialysate sodium. Low dialysate sodium concentration significantly reduced 48-h ambulatory BP compared with standard dialysate sodium in patients with IDH. These findings support low dialysate sodium as a major non-pharmacologic approach for BP management in patients with IDH. ClinicalTrials.gov study number NCT05430438.

Right heart failure as a cause of pulmonary congestion in pulmonary arterial hypertension.

Recent studies have shown that lung ultrasound-assessed pulmonary congestion is worse in heart failure when pulmonary vascular resistance (PVR) is increased, suggesting a paradoxical relationship between right heart failure and increased lung water content. Accordingly, we wondered if lung ultrasound would reveal otherwise clinically silent pulmonary congestion in patients with pulmonary arterial hypertension (PAH). All patients referred for suspicion of PAH in a tertiary centre from January 2020 to December 2022 underwent a complete diagnostic work-up including echocardiography, lung ultrasound and right heart catheterization. Pulmonary congestion was identified by lung ultrasound B-lines using an 8-site scan. The study enrolled 102 patients with idiopathic PAH (mean age 53 ± 13 years; 71% female). World Health Organization functional classes I, II, and III were found in 2%, 52%, and 46% of them, respectively. N-terminal pro-brain natriuretic peptide (NT-proBNP) was 377 pg/ml (interquartile range [IQR] 218-906). B-lines were identified in 77 out of 102 patients (75%), with a median of 3 [IQR 1-5]. At univariable analysis, B-lines were positively correlated with male sex, age, NT-proBNP, systolic pulmonary artery pressure (sPAP), right atrial pressure (RAP), PVR, left ventricular end-diastolic volume and tricuspid annular plane systolic excursion (TAPSE), and negatively with cardiac output and stroke volume. At multivariable analysis, RAP (p < 0.001), TAPSE/sPAP (p = 0.001), and NT-proBNP (p = 0.04) were independent predictors of B-lines. Lung ultrasound commonly discloses pulmonary congestion in PAH. This finding is related to right ventricular to pulmonary artery uncoupling, and may tentatively be explained by increased central venous pressure impeding lymphatic outflow.

Value of Lung Ultrasound Sonography B-Lines Quantification as a Marker of Heart Failure in COPD Exacerbation.

Identifying heart failure (HF) in acute exacerbation of chronic obstructive pulmonary disease (AECOPD) can be challenging. Lung ultrasound sonography (LUS) B-lines quantification has recently gained a large place in the diagnosis of HF, but its diagnostic performance in AECOPD remains poorly studied. This study aimed to assess the contribution of LUS B-lines score (LUS score) in the diagnosis of HF in AECOPD patients. This is a prospective cross-sectional multicenter cohort study including patients admitted to the emergency department for AECOPD. All included patients underwent LUS. A lung ultrasound score (LUS score) based on B-lines calculation was assessed. A cardiac origin of dyspnea was retained for a LUS score greater than 15. HF diagnosis was based on clinical examination, pro-brain natriuretic peptide levels, and echocardiographic findings. The LUS score diagnostic performance was assessed by receiver operating characteristic (ROC) curve, sensitivity, specificity, and likelihood ratio at the best cutoffs. We included 380 patients, mean age was 68±11.6 years, sex ratio (M/F) 1.96. Patients were divided into two groups: the HF group [n=157 (41.4%)] and the non-HF group [n=223 (58.6%)]. Mean LUS score was higher in the HF group (26.8±8.4 vs 15.3±7.1; p<0.001). The mean LUS score in the HF patients with reduced LVEF was 29.2±8.7, and was 24.5±7.6 in the HF patients with preserved LVEF. LUS score area under ROC curve for the diagnosis of HF was 0.71 [0.65-0.76]. The best sensitivity (89% [85.9-92,1]) was observed at the threshold of 5; the best specificity (85% [81.4-88.6]) was observed at the threshold of 30. Correlation between LUS score and E/E' ratio was good (R=0.46, p=0.0001). Our results suggest that LUS score could be helpful and should be considered in the diagnostic approach of HF in AECOPD patients, at least as a ruling in test.

Association of Lung Ultrasound B-Lines with Left Ventricular Diastolic Function in Clinically Euvolemic Haemodialysis Patients

Introduction: Left ventricular diastolic dysfunction (LVDD) frequently occurs in haemodialysis patients and is associated with adverse outcomes. Lung ultrasound (LUS) has been recently proposed for the quantification of extravascular lung water through assessment of B-lines. LUS findings and their relationship with LVDD in clinically euvolemic haemodialysis patients were investigated in this study. Methods: Echocardiography and LUS examinations were performed on each patient. Multivariate linear regression and forward stepwise logistic regression were performed to determine the relationship between B-lines and LVDD. A receiver operating characteristic (ROC) curve with area under the curve (AUC) was calculated to determine the accuracy of B-lines for evaluating LVDD. Results: A total of 119 patients were enrolled. The number of B-lines was statistically related to echocardiographic parameters (LAVI, LVEDVI, E/A, and E/e′) of diastolic function, while the relationship between B-lines and LVEF disappeared after adjusting for potential confounding factors. Additionally, compared with the mild B-line group (B-lines: <14), the moderate (B-lines: 14–30) and severe B-line groups (B-lines: >30) were associated with an increased risk of LVDD (OR 24.344, 95% CI 4.854–122.084, p < 0.001, and OR 94.552, 95% CI 9.617–929.022, p < 0.001, respectively). Furthermore, the AUC of the ROC curve for B-lines predicting LVDD was 0.845, and the cut-off of B-lines was 14.5 (sensitivity 64.91%, specificity 93.55%). Conclusion: LUS B-lines were closely associated with left ventricular diastolic function in clinically euvolemic haemodialysis patients. Moreover, our findings suggested a B-line ≥14.5 as a reliable cut-off value for identifying patients with LVDD. LUS B-lines may be used as a novel indicator for evaluating LVDD.

Lung ultrasound, echocardiography and fluid loading for the differential diagnosis of pulmonary hypertension

Abstract Background There may be interest in combining echocardiography and lung ultrasound for the differential diagnosis between pulmonary arterial hypertension (PAH) and post-capillary pulmonary hypertension on heart failure with preserved ejection fraction (PH-HFpEF). Methods Patients referred for PH underwent a right heart catheterization, echocardiography and lung ultrasound before and after rapid infusion of 7 ml/kg of saline. A 7-points echocardiographic score based on cardiac chamber dimensions and estimates of filling pressures was implemented for the prediction of pre-capillary PH. Pulmonary congestion was identified by lung ultrasound B-lines. Results The study enrolled 70 patients with PAH and 77 patients with HFpEF. The PAH patients had a higher echocardiographic score (3.5±1.8 v 1.6±1.5, p &amp;lt;0.001). Figure 1 represents the typical baseline echocardiographic components of pre-capillary pulmonary hypertension prediction score and pre- and post-fluid loading lung ultrasound imaging from patients with PAH and HFpEF respectively. The HFpEF patients had more B-lines both before (8.1±4.2 vs 5.1±3.0; p &amp;lt;0.001) and after fluid loading (14.6±5.4 vs 7.6±3.5; p &amp;lt;0.001), and a more important increase (Δ) of B-lines after fluid loading (6.5±2.9 vs 2.5±1.6; p &amp;lt;0.001). The sensitivity and specificity of the echocardiographic score alone for PAH were 0.91 and 0.49 respectively [area under the curve (AUC) 0.78]. The AUC for PAH was improved by addition of smaller ΔB-lines to the echocardiography prediction score after fluid loading, with significant increase in sensitivity [0.94 (95% CI 0.89;1.00)] and specificity [0.91 (95% CI 0.84;0.97)] and a positive predictive value of 0.90 (CI 0.84;0.97) and a negative predictive value of 0.95 (CI 0.89;1.00). Figure 2 represents the bar plot of AUC for echocardiographic score, pre- fluid loading B-lines, delta E/e', delta B-lines, post- fluid loading E/e', post- fluid loading B-lines, in ascending order. Conclusion Lung ultrasound combined with echocardiography at baseline and after fluid loading has an incremental value for the differential diagnosis between PAH and PH-HFpEF.Figure 1Figure 2

Right heart failure as a source of B-lines at lung ultrasound: prevalence and functional correlates

Abstract Background Lung ultrasound is part of the standard transthoracic examination and B-lines provide an index of extravascular lung water allowing to measure pulmonary congestion in left heart failure. However, pulmonary congestion can also appear as a consequence of right heart failure and it has been assumed that depends on the increase in central venous pressure increasing the resistance to lymphatic drainage. Aim of this study was to assess the prevalence of lung B-lines in a clinical model of pure right heart failure due to idiopathic pulmonary arterial hypertension (PAH) and its correlation with haemodynamic parameters. Methods All patients referred for suspicion of pulmonary hypertension in a single tertiary centre from January 2020 to December 2022 underwent a complete diagnostic work-up including echocardiography, lung ultrasound and right heart catheterization. The diagnosis of PAH was made following the current international recommendations. Pulmonary congestion was identified by lung ultrasound B-lines using an 8-site scan. Results The study enrolled 102 patients with PAH. Patients’ characteristics are shown in Table 1. The median lung B-lines were 3 [IQR: 1-5]. Results of univariate and multivariate analysis of B-lines predictors are shown in Table 1. Right atrial pressure (RAP), tricuspid annular plane excursion (TAPSE)/ Systolic pulmonary pressure (sPAP) ratio and pro hormone brain natriuretic peptide (proBNP) were independent predictors of B lines. Conclusion RAP, TAPSE/sPAP and proBNP were independent predictors of B lines in PAH patients according to the pathophysiological hypothesis that B-lines depends on the increase in central venous pressure increasing the resistance to lymphatic drainage.Table 1

Automatic detection of lung ultrasound b-lines over heart cycles for assessing pulmonary edema

Excess extravascular lung water (EVLW) is a common consequence for patients with congestive heart failure, inflammatory conditions, or acute respiratory distress syndrome. Computed tomography (CT) is widely used to assess EVLW, but with a higher radiation dose and logistical complexity. Lung ultrasound (LUS) using B-line artifacts demonstrates a reasonable correlation with EVLW, but user experience with the acquisition technique, equipment-dependent factors and the subjective analysis of the B-line artifacts results in significant inter-observer variability. We propose a technique to automatically detect lung ultrasound B-lines over heart cycles. The method first extracts B-mode image features from videos in a region of interest (ROI). A ResNet50-UNet network is then applied to segment regions of B-lines. This technique was performed on 8 videos (i.e., 4 patients versus 4 controls with the duration of each video 2–3 s, resolution 1024 × 758 pixels, and frame rate 28 fps). The training accuracy and lossvalue of proposed models were 96.5% and 0.05, respectively. The paired t-test statical analysis shows that there is significant difference (p-value = 0.0035) of total number of B-line between normal and lungs with edema. The proposed method improves the accuracy for counting the B-lines and reduces the labor work and intra-observer variability from different users.

Lung Ultrasound, Echocardiography, and Fluid Challenge for the Differential Diagnosis of Pulmonary Hypertension

The differential diagnosis between pulmonary arterial hypertension (PAH) and postcapillary pulmonary hypertension (PH) in heart failure with preserved ejection fraction (HFpEF) is sometimes difficult despite guidelines-derived standardized step-by-step diagnostic algorithms. We therefore explored the added value of lung ultrasound to a previously validated echocardiographic score of right heart catheterization measurements. Patients referred for PH underwent a right heart catheterization, echocardiography, and lung ultrasound before and after rapid infusion of 7mL/kg of saline. A 7-point echocardiographic score based on cardiac chamber dimensions and estimates of filling pressures was implemented for the prediction of precapillary PH. Pulmonary congestion was identified by lung ultrasound B lines. The study enrolled 70 patients with PAH and 77 patients with HFpEF. The PAH patients had a higher echocardiographic score (3.5±1.8 vs 1.6±1.5; P<.001). The HFpEF patients had more B lines both before (8.1±4.2 vs 5.1±3.0; P<.001) and after fluid challenge (14.6±5.4 vs 7.6±3.5; P<.001) and a more important increase (Δ) of B lines after fluid challenge (6.5±2.9 vs 2.5±1.6; P<.001). The sensitivity and specificity of the echocardiographic score (cutoff ≥2) alone for PAH were 0.91 and 0.49, respectively (area under the curve of 0.78). The best diagnostic improvement was observed with addition of ΔB lines+E/e' post-fluid challenge to the echocardiographic score, with a significant increase of the area under the curve (0.98) and (with a cutoff given by the presence of echo score ≥2, ΔB lines <4 and E/e' post < 11) a sensitivity of 0.90 (95% CI, 0.83; 0.97) and specificity of 0.84 (95% CI, 0.76; 0.93). Lung ultrasound combined with echocardiography at baseline and after fluid challenge has an incremental value for the differential diagnosis between PAH and PH-HFpEF.

Lung Ultrasound Abnormalities in Patients Without Pulmonary Pathology Prior to Surgery.

The occurrence of lung ultrasound abnormalities in patients without lung disease remains uncertain, while patients with respiratory disease often exhibit such abnormalities. The primary aim was to identify pathological ultrasonographic pulmonary findings and their correlation with baseline diseases and static lung compliance in patients without any pre-existing respiratory conditions. This prospective observational study enrolled a series of surgical patients with no history of pulmonary pathology (n = 104). Baseline diseases and patients' physical status classification, based on the American Society of Anesthesiologists (ASA), were documented by reviewing medical records. Prior to surgery, a lung ultrasound was performed to assess pulmonary changes. During surgery with general anesthesia, static lung compliance was measured. The Spearman correlation coefficient was employed to determine the correlation between the two variables. Twenty-four patients (23.07%) exhibited 1 - 2 B-lines in certain lung fields. Seven patients (6.7%) had an ultrasound B-line score > 0 (indicating ≥ 3 B-lines). Among these patients, the average number of lung fields with ≥ 3 B-lines was 3.71 ± 2.43. Patients with systemic diseases (ASA ≥ 2) displayed a higher number of B-lines compared to ASA I patients (P-value = 0.039). Pleural irregularities were found in 10 patients (9.6%), while atelectasis and pleural effusion were observed in five (4.8%) and four (3.8%) patients, respectively. The mean lung compliance value was 56.78 ± 15.33. No correlation was observed between the total score of the B-lines and lung compliance (Spearman's correlation: rho = -0.028, P-value = 0.812). Patients without pulmonary pathology may exhibit ultrasound pulmonary abnormalities, which tend to increase with higher ASA scores and do not appear to have a correlation with static lung compliance.