Diagnostic value of B-Type natriuretic peptide and chest radiographic findings in patients with acute dyspnea

Deep learning to detect left ventricular structural abnormalities in chest X-rays

BACKGROUND AND AIMS

Early identification of cardiac structural abnormalities indicative of heart failure is crucial to improving patient outcomes. Chest X-rays (CXRs) are routinely conducted on a broad population of patients, presenting an opportunity to build scalable screening tools for structural abnormalities indicative of Stage B or worse heart failure with deep learning methods. In this study, a model was developed to identify severe left ventricular hypertrophy (SLVH) and dilated left ventricle (DLV) using CXRs.

METHODS

A total of 71 589 unique CXRs from 24 689 different patients completed within 1 year of echocardiograms were identified. Labels for SLVH, DLV, and a composite label indicating the presence of either were extracted from echocardiograms. A deep learning model was developed and evaluated using area under the receiver operating characteristic curve (AUROC). Performance was additionally validated on 8003 CXRs from an external site and compared against visual assessment by 15 board-certified radiologists.

RESULTS

The model yielded an AUROC of 0.79 (0.76-0.81) for SLVH, 0.80 (0.77-0.84) for DLV, and 0.80 (0.78-0.83) for the composite label, with similar performance on an external data set. The model outperformed all 15 individual radiologists for predicting the composite label and achieved a sensitivity of 71% vs. 66% against the consensus vote across all radiologists at a fixed specificity of 73%.

CONCLUSIONS

Deep learning analysis of CXRs can accurately detect the presence of certain structural abnormalities and may be useful in early identification of patients with LV hypertrophy and dilation. As a resource to promote further innovation, 71 589 CXRs with adjoining echocardiographic labels have been made publicly available.

Clearing the Congestion: Chest Radiography and BNP to Rule-out Congestive Heart Failure

PURPOSE

Ruling out congestive heart failure (CHF) is clinically important in Emergency Department (ED) patients. Normal serum brain natriuretic peptide (BNP) represents an important reference standard for excluding CHF. Results of chest radiographs (CXR) are also considered and, when discordant with BNP levels, may result in a clinical dilemma. The present study was designed to elucidate factors associated with CHF on CXR in an ED cohort with normal BNP.

MATERIALS AND METHODS

All adults at our urban health system's EDs who underwent CXR within 24 hours and had a normal BNP (<300 pg/mL) within 24 hours of CXR were retrospectively identified. Of these, 0.9% (8/862) had equivocal CXRs and was excluded. Demographics, comorbidities, CXR report results for CHF, and portable technique were noted. Logistic regression was used to assess factors that are associated with the presence of CHF on CXR.

RESULTS

The study cohort comprised 854 patients (433 men, mean age 60.99±15.30) with normal BNP; 91.5% (781/854) had no CHF on CXR and 8.5% (73/854) had CHF. Patients with CHF on CXR had a higher body mass index (32.9 vs. 29.8 kg/m 2 , P =0.0205) were more likely to have a history of CHF or diabetes with complications (OR: 2.72 and 2.53, respectively), had higher serum BNP levels (median 164 vs. 98 pg/mL, P =4.91×10 -5 ), and underwent portable examination more frequently (86.3% vs. 57.5%, OR: 4.65).

CONCLUSIONS

Normal serum BNP was concordant with CXR results, adding diagnostic confidence in ruling out CHF in a large majority of ED patients. A higher body mass index, history of CHF, and diabetes with complications and portable CXR technique were associated with CHF on CXR among the minority with normal BNP.

A systemic review and meta-analysis comparing the ability of diagnostic of the third heart sound and left ventricular ejection fraction in heart failure

Objective

This study aimed to compare the sensitivity and specificity of diagnosis between the third heart sound (S3) and left ventricular ejection fraction (LVEF) in heart failure (HF).

Methods

Relevant studies were searched in PubMed, SinoMed, China National Knowledge Infrastructure, and the Cochrane Trial Register until February 20, 2022. The sensitivity, specificity, likelihood ratio (LR), and diagnostic odds ratio (DOR) were pooled. The symmetric receiver operator characteristic curve (SROC) and Fagan’s nomogram were drawn. The source of heterogeneity was explored by meta-regression and subgroup analysis.

Results

A total of 19 studies, involving 5,614 participants, were included. The combined sensitivity of S3 was 0.23 [95% confidence interval (CI) (0.15–0.33), specificity was 0.94 [95% CI (0.82–0.98)], area under the SROC curve was 0.49, and the DOR was 4.55; while the sensitivity of LVEF was 0.70 [95% CI (0.53–0.83)], specificity was 0.79 [95% CI (0.75–0.82)], area under the SROC curve was 0.79, and the DOR was 8.64. No publication bias was detected in Deeks’ funnel plot. The prospective design, partial verification bias, and blind contributed to the heterogeneity in specificity, while adequate description of study participants contributed to the heterogeneity in sensitivity. In Fagan’s nomogram, the post-test probability was 48% when the pre-test probability was set as 20%, while in LVEF, the post-test probability was 45% when the pre-test probability was set as 20%.

Conclusion

The use of S3 alone presented lower sensitivity in diagnosing HF compared with LVEF, whereas it was useful in early pathological assessment.

2022 AHA/ACC/HFSA Guideline for the Management of Heart Failure: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2022 AHA/ACC/HFSA Guideline for the Management of Heart Failure" replaces the "2013 ACCF/AHA Guideline for the Management of Heart Failure" and the "2017 ACC/AHA/HFSA Focused Update of the 2013 ACCF/AHA Guideline for the Management of Heart Failure." The 2022 guideline is intended to provide patient-centric recommendations for clinicians to prevent, diagnose, and manage patients with heart failure.

METHODS

A comprehensive literature search was conducted from May 2020 to December 2020, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from MEDLINE (PubMed), EMBASE, the Cochrane Collaboration, the Agency for Healthcare Research and Quality, and other relevant databases. Additional relevant clinical trials and research studies, published through September 2021, were also considered. This guideline was harmonized with other American Heart Association/American College of Cardiology guidelines published through December 2021. Structure: Heart failure remains a leading cause of morbidity and mortality globally. The 2022 heart failure guideline provides recommendations based on contemporary evidence for the treatment of these patients. The recommendations present an evidence-based approach to managing patients with heart failure, with the intent to improve quality of care and align with patients' interests. Many recommendations from the earlier heart failure guidelines have been updated with new evidence, and new recommendations have been created when supported by published data. Value statements are provided for certain treatments with high-quality published economic analyses.

2022 AHA/ACC/HFSA Guideline for the Management of Heart Failure

AIM

The "2022 AHA/ACC/HFSA Guideline for the Management of Heart Failure" replaces the "2013 ACCF/AHA Guideline for the Management of Heart Failure" and the "2017 ACC/AHA/HFSA Focused Update of the 2013 ACCF/AHA Guideline for the Management of Heart Failure." The 2022 guideline is intended to provide patient-centric recommendations for clinicians to prevent, diagnose, and manage patients with heart failure.

METHODS

A comprehensive literature search was conducted from May 2020 to December 2020, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from MEDLINE (PubMed), EMBASE, the Cochrane Collaboration, the Agency for Healthcare Research and Quality, and other relevant databases. Additional relevant clinical trials and research studies, published through September 2021, were also considered. This guideline was harmonized with other American Heart Association/American College of Cardiology guidelines published through December 2021.

STRUCTURE

Heart failure remains a leading cause of morbidity and mortality globally. The 2022 heart failure guideline provides recommendations based on contemporary evidence for the treatment of these patients. The recommendations present an evidence-based approach to managing patients with heart failure, with the intent to improve quality of care and align with patients' interests. Many recommendations from the earlier heart failure guidelines have been updated with new evidence, and new recommendations have been created when supported by published data. Value statements are provided for certain treatments with high-quality published economic analyses.

Assessing congestion in acute heart failure using cardiac and lung ultrasound - a review

Introduction: Acute heart failure (AHF) is one of the leading causes of hospital admissions and is characterized by systemic and pulmonary congestion, which often precedes the overt clinical signs and symptoms. Echocardiography in the management of chronic HF is well described; however, there are less evidence regarding echocardiography and lung ultrasound (LUS) in the acute setting.Areas covered: We have summarized current evidence regarding the use of echocardiography and LUS for assessing congestion in patients with AHF. We discuss the value and reliability of handheld/pocketsize ultrasound devices in AHF.Expert opinion: Echocardiography is an essential tool for the diagnostic work up in patients with AHF. No individual parameter reliably detects congestion, thus the physician must integrate several measurements from the right and left heart. Novel methods and advances in cardiac imaging and clinical chemistry make it possible to detect congestion at an early stage. LUS is particularly helpful in assessing congestion, and it has demonstrated diagnostic, therapeutic, and prognostic value in AHF. LUS is relatively easy to learn and allows for quick assessment of the presence of pulmonary congestion and pleural effusion. We recommend integration of LUS for routine management of patients with AHF.

Diagnostic performance of congestion score index evaluated from chest radiography for acute heart failure in the emergency department: A retrospective analysis from the PARADISE cohort

BACKGROUND

Congestion score index (CSI), a semiquantitative evaluation of congestion on chest radiography (CXR), is associated with outcome in patients with heart failure (HF). However, its diagnostic value in patients admitted for acute dyspnea has yet to be evaluated.

METHODS AND FINDINGS

The diagnostic value of CSI for acute HF (AHF; adjudicated from patients' discharge files) was studied in the Pathway of dyspneic patients in Emergency (PARADISE) cohort, including patients aged 18 years or older admitted for acute dyspnea in the emergency department (ED) of the Nancy University Hospital (France) between January 1, 2015 and December 31, 2015. CSI (ranging from 0 to 3) was evaluated using a semiquantitative method on CXR in consecutive patients admitted for acute dyspnea in the ED. Results were validated in independent cohorts (N = 224). Of 1,333 patients, mean (standard deviation [SD]) age was 72.0 (18.5) years, 686 (51.5%) were men, and mean (SD) CSI was 1.42 (0.79). Patients with higher CSI had more cardiovascular comorbidities, more severe congestion, higher b-type natriuretic peptide (BNP), poorer renal function, and more respiratory acidosis. AHF was diagnosed in 289 (21.7%) patients. CSI was significantly associated with AHF diagnosis (adjusted odds ratio [OR] for 0.1 unit CSI increase 1.19, 95% CI 1.16-1.22, p < 0.001) after adjustment for clinical-based diagnostic score including age, comorbidity burden, dyspnea, and clinical congestion. The diagnostic accuracy of CSI for AHF was >0.80, whether alone (area under the receiver operating characteristic curve [AUROC] 0.84, 95% CI 0.82-0.86) or in addition to the clinical model (AUROC 0.87, 95% CI 0.85-0.90). CSI improved diagnostic accuracy on top of clinical variables (net reclassification improvement [NRI] = 94.9%) and clinical variables plus BNP (NRI = 55.0%). Similar diagnostic accuracy was observed in the validation cohorts (AUROC 0.75, 95% CI 0.68-0.82). The key limitation of our derivation cohort was its single-center and retrospective nature, which was counterbalanced by the validation in the independent cohorts.

CONCLUSIONS

In this study, we observed that a systematic semiquantified assessment of radiographic pulmonary congestion showed high diagnostic value for AHF in dyspneic patients. Better use of CXR may provide an inexpensive, widely, and readily available method for AHF triage in the ED.

Simple quantitative chest CT for pulmonary edema

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Quantitative CT is a highly accurate but underutilized method for identifying pulmonary edema on CT.

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There is a moderatelystrong correlation between CT HUs and CXR pulmonary edema grade in every lobe with correlation coefficients ranging from 0.585−0.685.

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CT Hounsfield unit measurement yields excellent accuracy in differentiating no edema from mild to severe edema, with AUCs up to 0.995 in the LUL.

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Qualitative CT with a % versus 84 % and specificity 95 % versus 78 Qualitative CT with a HU cut-off of -825 in the LUL is more sensitive (100% vs 84%) and specific (95% vs 78%) than qualitative CT.

Purpose

To determine the accuracy of quantitative CT to diagnose pulmonary edema compared to qualitative CT and CXR and to determine a threshold Hounsfield unit (HU) measurement for pulmonary edema on CT examinations.

Method

Electronic medical records were searched for patients with a billing diagnosis of heart failure and a Chest CT and CXR performed within three hours between 1/1/2016 to 10/1/2016, yielding 100 patients. CXR and CT examinations were scored for the presence and severity of edema, using a 0–5 scale, and CT HU measurements were obtained in each lobe. Polyserial correlation coefficients evaluated the association between CT HUs and CXR scores, and receiver operating characteristic (ROC) curve analysis determined a cutoff CT HU value for identification of pulmonary edema.

Results

Correlation between CT HU and CXR score was moderately strong (r = 0.585−0.685) with CT HU measurements demonstrating good to excellent accuracy in differentiating between no edema (grade 0) and mild to severe edema (grades 1–5) in every lobe, with AUCs ranging between 0.869 and 0.995. The left upper lobe demonstrated the highest accuracy, using a cutoff value of -825 HU (AUC of 0.995, sensitivity = 100 % and specificity = 95.1 %). Additionally, qualitative CT evaluation was less sensitive (84 %) than portable CXR in identifying pulmonary edema. However, quantitative CT evaluation was as sensitive as portable CXR (100 %) and highly specific (95 %).

Conclusions

Quantitative CT enables the identification of pulmonary edema with high accuracy and demonstrates a greater sensitivity than qualitative CT in assessment of pulmonary edema.

Artificial Intelligence-Enabled ECG Algorithm to Identify Patients With Left Ventricular Systolic Dysfunction Presenting to the Emergency Department With Dyspnea

BACKGROUND

Identification of systolic heart failure among patients presenting to the emergency department (ED) with acute dyspnea is challenging. The reasons for dyspnea are often multifactorial. A focused physical evaluation and diagnostic testing can lack sensitivity and specificity. The objective of this study was to assess the accuracy of an artificial intelligence-enabled ECG to identify patients presenting with dyspnea who have left ventricular systolic dysfunction (LVSD).

METHODS

We retrospectively applied a validated artificial intelligence-enabled ECG algorithm for the identification of LVSD (defined as LV ejection fraction ≤35%) to a cohort of patients aged ≥18 years who were evaluated in the ED at a Mayo Clinic site with dyspnea. Patients were included if they had at least one standard 12-lead ECG acquired on the date of the ED visit and an echocardiogram performed within 30 days of presentation. Patients with prior LVSD were excluded. We assessed the model performance using area under the receiver operating characteristic curve, accuracy, sensitivity, and specificity.

RESULTS

A total of 1606 patients were included. Median time from ECG to echocardiogram was 1 day (Q1: 1, Q3: 2). The artificial intelligence-enabled ECG algorithm identified LVSD with an area under the receiver operating characteristic curve of 0.89 (95% CI, 0.86-0.91) and accuracy of 85.9%. Sensitivity, specificity, negative predictive value, and positive predictive value were 74%, 87%, 97%, and 40%, respectively. To identify an ejection fraction <50%, the area under the receiver operating characteristic curve, accuracy, sensitivity, and specificity were 0.85 (95% CI, 0.83-0.88), 86%, 63%, and 91%, respectively. NT-proBNP (N-terminal pro-B-type natriuretic peptide) alone at a cutoff of >800 identified LVSD with an area under the receiver operating characteristic curve of 0.80 (95% CI, 0.76-0.84).

CONCLUSIONS

The ECG is an inexpensive, ubiquitous, painless test which can be quickly obtained in the ED. It effectively identifies LVSD in selected patients presenting to the ED with dyspnea when analyzed with artificial intelligence and outperforms NT-proBNP. Graphic Abstract: A graphic abstract is available for this article.

The diagnostic accuracy of lung auscultation in adult patients with acute pulmonary pathologies: a meta-analysis

The stethoscope is used as first line diagnostic tool in assessment of patients with pulmonary symptoms. However, there is much debate about the diagnostic accuracy of this instrument. This meta-analysis aims to evaluate the diagnostic accuracy of lung auscultation for the most common respiratory pathologies. Studies concerning adult patients with respiratory symptoms are included. Main outcomes are pooled estimates of sensitivity and specificity with 95% confidence intervals, likelihood ratios (LRs), area under the curve (AUC) of lung auscultation for different pulmonary pathologies and breath sounds. A meta-regression analysis is performed to reduce observed heterogeneity. For 34 studies the overall pooled sensitivity for lung auscultation is 37% and specificity 89%. LRs and AUC of auscultation for congestive heart failure, pneumonia and obstructive lung diseases are low, LR− and specificity are acceptable. Abnormal breath sounds are highly specific for (hemato)pneumothorax in patients with trauma. Results are limited by significant heterogeneity. Lung auscultation has a low sensitivity in different clinical settings and patient populations, thereby hampering its clinical utility. When better diagnostic modalities are available, they should replace lung auscultation. Only in resource limited settings, with a high prevalence of disease and in experienced hands, lung auscultation has still a role.

Imaging in patients with suspected acute heart failure: timeline approach position statement on behalf of the Heart Failure Association of the European Society of Cardiology

Acute heart failure is one of the main diagnostic and therapeutic challenges in clinical practice due to a non-specific clinical manifestation and the urgent need for timely and tailored management at the same time. In this position statement, the Heart Failure Association aims to systematize the use of various imaging methods in accordance with the timeline of acute heart failure care proposed in the recent guidelines of the European Society of Cardiology. During the first hours of admission the point-of-care focused cardiac and lung ultrasound examination is an invaluable tool for rapid differential diagnosis of acute dyspnoea, which is highly feasible and relatively easy to learn. Several portable and stationary imaging modalities are being increasingly used for the evaluation of cardiac structure and function, haemodynamic and volume status, precipitating myocardial ischaemia or valvular abnormalities, and systemic and pulmonary congestion. This paper emphasizes the central role of the full echocardiographic examination in the identification of heart failure aetiology, severity of cardiac dysfunction, indications for specific heart failure therapy, and risk stratification. Correct evaluation of cardiac filling pressures and accurate prognostication may help to prevent unscheduled short-term readmission. Alternative advanced imaging modalities should be considered to assist patient management in the pre- and post-discharge phase, including cardiac magnetic resonance, computed tomography, nuclear studies, and coronary angiography. The Heart Failure Association addresses this paper to the wide spectrum of acute care and heart failure specialists, highlighting the value of all available imaging techniques at specific stages and in common clinical scenarios of acute heart failure.

Diagnosis of Acute Heart Failure in the Emergency Department: An Evidence-Based Review

Heart failure is a common presentation to the emergency department (ED), which can be confused with other clinical conditions. This review provides an evidence-based summary of the current ED evaluation of heart failure. Acute heart failure is the gradual or rapid decompensation of heart failure, resulting from either fluid overload or maldistribution. Typical symptoms can include dyspnea, orthopnea, or systemic edema. The physical examination may reveal pulmonary rales, an S3 heart sound, or extremity edema. However, physical examination findings are often not sensitive or specific. ED assessments may include electrocardiogram, complete blood count, basic metabolic profile, liver function tests, troponin, brain natriuretic peptide, and a chest radiograph. While often used, natriuretic peptides do not significantly change ED treatment, mortality, or readmission rates, although they may decrease hospital length of stay and total cost. Chest radiograph findings are not definitive, and several other conditions may mimic radiograph findings. A more reliable modality is point-of-care ultrasound, which can facilitate the diagnosis by assessing for B-lines, cardiac function, and inferior vena cava size. These modalities, combined with clinical assessment and gestalt, are recommended.

B-lines by lung ultrasound predict heart failure in hospitalized patients with acute anterior wall STEMI

OBJECTIVE

B-line imaging by lung ultrasound (LUS) is a new tool for evaluating subclinical pulmonary congestion. The aim of this study was to explore the prognostic value of B-line number at admission in predicting symptomatic heart failure (HF) during hospitalization in acute anterior wall STEMI patients.

METHODS

This was a prospective cohort study which consecutively enrolled 96 anterior wall STEMI patients without dyspnea at admission. Pulmonary auscultation, NT-proBNP test, LUS, and echocardiography were performed within 5 hours after primary PCI. Rale occurrence, plasma NT-proBNP levels, B-line number, LVEF, E/e' were recorded, and their predictive value for HF in-hospital was analyzed.

RESULTS

A total of 19 patients developed symptomatic HF. Median B-line number, NT-proBNP levels, and E/e' in the HF group were higher than those of the nonheart-failure (NHF) group (P < 0.001) while LVEF was lower (P = 0.002). There was no statistical difference in rale occurrence between the two groups. Multivariate logistic regression demonstrated that B-lines, E/e', and NT-proBNP independently predicted HF during hospitalization. According to the area under the ROC curve, the strongest predictor is B-lines (0.972), followed by NT-proBNP (0.936) and E/e' (0.928), and combining the three indicators was better than any single parameter (P = 0.048). B-line cutoff ≥18 could well predict HF event with specificity and sensitivity of 94.7% and 94.8%, respectively.

CONCLUSION

Subclinical pulmonary congestion reflected by B-lines can independently predict symptomatic HF during hospitalization in patients with anterior wall STEMI, LUS will act as a complementary tool for evaluating cardiac function.

Significance of congestive heart failure as a cause of pleural effusion: Pilot data from a large multidisciplinary teaching hospital

BACKGROUND

Epidemiological data on the causes of pleural effusion (PE) are scarce. Data on the local prevalence of various causes of PE may play a crucial role in the management strategy of patients with PE. The aim of the study was to investigate the causes of PE and to assess 30-day mortality rate in unselected adult patients treated in a large, multidisciplinary hospital.

METHODS

Retrospective analysis of medical records, including chest radiographs, of 2835 consecutive patients admitted to the hospital was performed. Radiograhic signs of PE were found in 195 of 1936 patients in whom chest radigraphs were available. These patients formed the study group.

RESULTS

The leading causes of PE were as follows: congestive heart failure (CHF; 37.4%), pneumonia (19.5%), malignancy (15.4%), liver cirrhosis (4.2%) and pulmonary embolism. The cause of PE in 6.7% patients was not established. There was a significant predominance of small volume PE as compared to a moderate or large volume PEs (153, 28 and 14 patients, respectively). Almost 80% of patients with CHF presented with small volume PE, while almost 50% of patients with malignant PE demonstrated moderate or large volume PE. Thirty-day mortality rate ranged from 0% for tuberculous pleurisy to 40% for malignant PE (MPE).

CONCLUSIONS

Pleural effusion was found in 10.1% of patients treated in a large multidisciplinary hospital. CHF was the leading cause of PE. Although 30-day mortality in patients with CHF was rela-tively high, it was lower than that in parapneumonic PE and MPE.

Emergency department ultrasound for the detection of B-lines in the early diagnosis of acute decompensated heart failure: a systematic review and meta-analysis

OBJECTIVES

Dyspnea is a common presenting problem that creates a diagnostic challenge for physicians in the emergency department (ED). While the differential diagnosis is broad, acute decompensated heart failure (ADHF) is a frequent cause that can be challenging to differentiate from other etiologies. Recent studies have suggested a potential diagnostic role for emergency lung ultrasound (US). The objective of this systematic review was to assess the accuracy of early bedside lung US in patients presenting to the ED with dyspnea.

METHODS

A systematic search of EMBASE, PubMed, and the Cochrane Library was performed in addition to a grey literature search. We selected prospective studies that reported on the sensitivity and specificity of B-lines from early lung ultrasound in dyspneic patients presenting to the ED. Selected studies underwent quality assessment using the Critical Appraisal and Skills Program (CASP) questionnaire.

DATA EXTRACTION AND SYNTHESIS

The search yielded 3674 articles; seven studies met inclusion criteria and fulfilled CASP requirements for a total of 1861 patients. Summary statistics from the meta-analysis showed that as a diagnostic test for ADHF, bedside lung US had a pooled sensitivity of 82.5% (95% confidence interval [CI]=66.4% to 91.8%) and a pooled specificity of 83.6% (95% CI=72.4% to 90.8%).

CONCLUSIONS

Our results suggest that in patients presenting to the ED with undifferentiated dyspnea, B-lines from early bedside lung US may be reliably used as an adjunct to current diagnostic methods. The incorporation of lung US may lead to more appropriate and timely diagnosis of patients with undifferentiated ADHF.

Role of Biomarkers for the Prevention, Assessment, and Management of Heart Failure: A Scientific Statement From the American Heart Association

BACKGROUND AND PURPOSE

Natriuretic peptides have led the way as a diagnostic and prognostic tool for the diagnosis and management of heart failure (HF). More recent evidence suggests that natriuretic peptides along with the next generation of biomarkers may provide added value to medical management, which could potentially lower risk of mortality and readmissions. The purpose of this scientific statement is to summarize the existing literature and to provide guidance for the utility of currently available biomarkers.

METHODS

The writing group used systematic literature reviews, published translational and clinical studies, clinical practice guidelines, and expert opinion/statements to summarize existing evidence and to identify areas of inadequacy requiring future research. The panel reviewed the most relevant adult medical literature excluding routine laboratory tests using MEDLINE, EMBASE, and Web of Science through December 2016. The document is organized and classified according to the American Heart Association to provide specific suggestions, considerations, or contemporary clinical practice recommendations.

RESULTS

A number of biomarkers associated with HF are well recognized, and measuring their concentrations in circulation can be a convenient and noninvasive approach to provide important information about disease severity and helps in the detection, diagnosis, prognosis, and management of HF. These include natriuretic peptides, soluble suppressor of tumorgenicity 2, highly sensitive troponin, galectin-3, midregional proadrenomedullin, cystatin-C, interleukin-6, procalcitonin, and others. There is a need to further evaluate existing and novel markers for guiding therapy and to summarize their data in a standardized format to improve communication among researchers and practitioners.

CONCLUSIONS

HF is a complex syndrome involving diverse pathways and pathological processes that can manifest in circulation as biomarkers. A number of such biomarkers are now clinically available, and monitoring their concentrations in blood not only can provide the clinician information about the diagnosis and severity of HF but also can improve prognostication and treatment strategies.

[Usefulness of natriuretic peptide testing and Doppler echocardiography at bedside in the diagnosis of acute heart failure]

Acute heart failure is a common condition that leads to hospital admission, with important mortality and readmission rates. A prompt and accurate diagnosis of this condition by hospitalists is essential for an early and tailored medical management. The use of natriuretic peptide testing (BNP and NT-proBNP) through a two cut-point strategy is currently recommended as the first-line diagnostic complement to the initial clinical evaluation in the acute care setting. Transthoracic Doppler echocardiography is an other noninvasive method that can be used at bedside, especially in patients with intermediate, inconclusive natriuretic peptides levels. In this regard, left ventricular ejection fraction and several simple Doppler indexes (restrictive mitral filling pattern, spectral tissue Doppler E/e' ratio), have been validated in the emergency diagnosis of acute heart failure. The aim of the present review is to overview the respective contribution of natriuretic peptides and Doppler echocardiography at bedside to the diagnosis of acute heart failure in the acute care setting.

Diagnosing Acute Heart Failure in the Emergency Department: A Systematic Review and Meta-analysis

BACKGROUND

Acute heart failure (AHF) is one of the most common diagnoses assigned to emergency department (ED) patients who are hospitalized. Despite its high prevalence in the emergency setting, the diagnosis of AHF in ED patients with undifferentiated dyspnea can be challenging.

OBJECTIVES

The primary objective of this study was to perform a systematic review and meta-analysis of the operating characteristics of diagnostic elements available to the emergency physician for diagnosing AHF. Secondary objectives were to develop a test-treatment threshold model and to calculate interval likelihood ratios (LRs) for natriuretic peptides (NPs) by pooling patient-level results.

METHODS

PubMed, EMBASE, and selected bibliographies were searched from January 1965 to March 2015 using MeSH terms to address the ability of the following index tests to predict AHF as a cause of dyspnea in adult patients in the ED: history and physical examination, electrocardiogram, chest radiograph (CXR), B-type natriuretic peptide (BNP), N-terminal proB-type natriuretic peptide (NT-proBNP), lung ultrasound (US), bedside echocardiography, and bioimpedance. A diagnosis of AHF based on clinical data combined with objective test results served as the criterion standard diagnosis. Data were analyzed using Meta-DiSc software. Authors of all NP studies were contacted to obtain patient-level data. The Quality Assessment Tool for Diagnostic Accuracy Studies-2 (QUADAS-2) for systematic reviews was utilized to evaluate the quality and applicability of the studies included.

RESULTS

Based on the included studies, the prevalence of AHF ranged from 29% to 79%. Index tests with pooled positive LRs ≥ 4 were the auscultation of S3 on physical examination (4.0, 95% confidence interval [CI] = 2.7 to 5.9), pulmonary edema on both CXR (4.8, 95% CI = 3.6 to 6.4) and lung US (7.4, 95% CI = 4.2 to 12.8), and reduced ejection fraction observed on bedside echocardiogram (4.1, 95% CI = 2.4 to 7.2). Tests with low negative LRs were BNP < 100 pg/mL (0.11, 95% CI = 0.07 to 0.16), NT-proBNP < 300 pg/mL (0.09, 95% CI = 0.03 to 0.34), and B-line pattern on lung US LR (0.16, 95% CI = 0.05 to 0.51). Interval LRs of BNP concentrations at the low end of "positive" results as defined by a cutoff of 100 pg/mL were substantially lower (100 to 200 pg/mL; 0.29, 95% CI = 0.23 to 0.38) than those associated with higher BNP concentrations (1000 to 1500 pg/mL; 7.12, 95% CI = 4.53 to 11.18). The interval LR of NT-proBNP concentrations even at very high values (30,000 to 200,000 pg/mL) was 3.30 (95% CI = 2.05 to 5.31).

CONCLUSIONS

Bedside lung US and echocardiography appear to the most useful tests for affirming the presence of AHF while NPs are valuable in excluding the diagnosis.

Point-of-Care Multi-Organ Ultrasound Improves Diagnostic Accuracy in Adults Presenting to the Emergency Department with Acute Dyspnea

Introduction

Determining the etiology of acute dyspnea in emregency department (ED) patients is often difficult. Point-of-care ultrasound (POCUS) holds promise for improving immediate diagnostic accuracy (after history and physical), thus improving use of focused therapies. We evaluate the impact of a three-part POCUS exam, or “triple scan” (TS) – composed of abbreviated echocardiography, lung ultrasound and inferior vena cava (IVC) collapsibility assessment – on the treating physician’s immediate diagnostic impression.

Methods

A convenience sample of adults presenting to our urban academic ED with acute dyspnea (Emergency Severity Index 1, 2) were prospectively enrolled when investigator sonographers were available. The method for performing components of the TS has been previously described in detail. Treating physicians rated the most likely diagnosis after history and physical but before other studies (except electrocardiogram) returned. An investigator then performed TS and disclosed the results, after which most likely diagnosis was reassessed. Final diagnosis (criterion standard) was based on medical record review by expert emergency medicine faculty blinded to TS result. We compared accuracy of pre-TS and post-TS impression (primary outcome) with McNemar’s test. Test characteristics for treating physician impression were also calculated by dichotomizing acute decompensated heart failure (ADHF), chronic obstructive pulmonary disease (COPD) and pneumonia as present or absent.

Results

57 patients were enrolled with the leading final diagnoses being ADHF (26%), COPD/asthma (30%), and pneumonia (28%). Overall accuracy of the treating physician’s impression increased from 53% before TS to 77% after TS (p=0.003). The post-TS impression was 100% sensitive and 84% specific for ADHF.

Conclusion

In this small study, POCUS evaluation of the heart, lungs and IVC improved the treating physician’s immediate overall diagnostic accuracy for ADHF, COPD/asthma and pneumonia and was particularly useful to immediately exclude ADHF as the cause of acute dyspnea.

[Diagnostic accuracy for heart failure – data from the Akershus Cardiac Examination 2 Study]

BACKGROUND

Diagnosing heart failure in an on-call setting can be difficult, and international studies report diagnostic accuracy among duty doctors, as measured using area under the ROC curve (AUC), to be 0.76-0.90. This study has examined the accuracy with which doctors in the internal medicine out-of-hours service in a Norwegian university hospital distinguish heart failure from no heart failure in patients with dyspnoea.

MATERIAL AND METHOD

Information was gathered on 468 patients admitted to Akershus University Hospital with dyspnoea between June 2009 and November 2010, and 314 patients were included in the study. The duty doctors estimated the probability of heart failure (0-100%) before N-terminal pro-B-type natriuretic peptide (NTproBNP) concentrations were known. The final diagnosis for the hospital admission was made retrospectively by two independent doctors after review of the medical records, including supplementary tests and the patient outcome.

RESULTS

Heart failure was considered the cause of hospitalisation in 143 patients (46%). Patients with heart failure were older, more often men, had a higher prevalence of heart disease, reduced/impaired renal function, and higher NTproBNP concentrations than patients with non-heart failure dyspnoea. The diagnostic accuracy among duty doctors for heart failure (AUC) was 0.86 (95% confidence interval 0.82-0.90). The doctors' diagnostic accuracy was lower when the patient had heart failure with left ventricular ejection fraction [LVEF] ≥ 50% (n=52): AUC 0.83 (0.77-0.87).

INTERPRETATION

The duty doctors at Akershus University Hospital from 2009-2010 demonstrated similar diagnostic accuracy for heart failure as previously reported from international centres. Diagnostic accuracy was lower for heart failure patients with LVEF ≥ 50%.

Lung Ultrasound-Implemented Diagnosis of Acute Decompensated Heart Failure in the ED: A SIMEU Multicenter Study

BACKGROUND

Lung ultrasonography (LUS) has emerged as a noninvasive tool for the differential diagnosis of pulmonary diseases. However, its use for the diagnosis of acute decompensated heart failure (ADHF) still raises some concerns. We tested the hypothesis that an integrated approach implementing LUS with clinical assessment would have higher diagnostic accuracy than a standard workup in differentiating ADHF from noncardiogenic dyspnea in the ED.

METHODS

We conducted a multicenter, prospective cohort study in seven Italian EDs. For patients presenting with acute dyspnea, the emergency physician was asked to categorize the diagnosis as ADHF or noncardiogenic dyspnea after (1) the initial clinical assessment and (2) after performing LUS ("LUS-implemented" diagnosis). All patients also underwent chest radiography. After discharge, the cause of each patient's dyspnea was determined by independent review of the entire medical record. The diagnostic accuracy of the different approaches was then compared.

RESULTS

The study enrolled 1,005 patients. The LUS-implemented approach had a significantly higher accuracy (sensitivity, 97% [95% CI, 95%-98.3%]; specificity, 97.4% [95% CI, 95.7%-98.6%]) in differentiating ADHF from noncardiac causes of acute dyspnea than the initial clinical workup (sensitivity, 85.3% [95% CI, 81.8%-88.4%]; specificity, 90% [95% CI, 87.2%-92.4%]), chest radiography alone (sensitivity, 69.5% [95% CI, 65.1%-73.7%]; specificity, 82.1% [95% CI, 78.6%-85.2%]), and natriuretic peptides (sensitivity, 85% [95% CI, 80.3%-89%]; specificity, 61.7% [95% CI, 54.6%-68.3%]; n = 486). Net reclassification index of the LUS-implemented approach compared with standard workup was 19.1%.

CONCLUSIONS

The implementation of LUS with the clinical evaluation may improve accuracy of ADHF diagnosis in patients presenting to the ED.

TRIAL REGISTRY

Clinicaltrials.gov; No.: NCT01287429; URL: www.clinicaltrials.gov.

Extension of the Thoracic Spine Sign: A New Sonographic Marker of Pleural Effusion

OBJECTIVES

Dyspnea is a common emergency department (ED) condition, which may be caused by pleural effusion and other thoracic diseases. We present data on a new sonographic marker, the extension of the thoracic spine sign, for diagnosis of pleural effusion.

METHODS

In this prospective study, we enrolled a convenience sample of undifferentiated patients who underwent computed tomography (CT) of the abdomen or chest, which was performed as part of their emergency department evaluations. Patients underwent chest sonography to assess the utility of the extension of the thoracic spine sign for diagnosing pleural effusion. The point-of-care sonographic examinations were performed and interpreted by emergency physicians who were blinded to information in the medical records. Sonographic results were compared to radiologists' interpretations of the CT results, which were considered the criterion standard.

RESULTS

Forty-one patients were enrolled, accounting for 82 hemithoraces. Seven hemithoraces were excluded from the analysis due to various limitations, leaving 75 hemithoraces for the final analysis. The median time for completion of the sonographic examination was 3 minutes. The sensitivity and specificity for extension of the thoracic spine were 73.7% (95% confidence interval [CI], 48.6%-89.9%) and 92.9% (95%CI, 81.9%-97.7%), respectively. Overall, there were 5 hemithoraces with false-negative results when using the extension sign. Of those 5 cases, 4 were found to have trace pleural effusions on CT. When trace pleural effusions were excluded in a subgroup analysis, the sensitivity and specificity of extension of the thoracic spine were 92.9% (95% CI, 64.2%-99.6%) and 92.9% (95% CI, 81.9%-97.7%).

CONCLUSIONS

We found the extension of the thoracic spine sign to be an excellent diagnostic tool for clinically relevant pleural effusion.

Potential impact of N-terminal pro-BNP testing on the emergency department evaluation of acute dyspnea

Objectives:

Measurement of the serum B-type natriuretic peptide (BNP) level and more recently its precursor, N-terminal proBNP (NT-proBNP), has been advocated to facilitate the diagnosis of heart failure in the emergency department (ED). We sought to determine the potential impact of adding NT-proBNP testing to the routine evaluation of emergency patients with acute dyspnea.

Methods:

This prospective cohort study enrolled a convenience sample of acutely dyspneic patients at a tertiary care ED. We excluded trauma patients and those under 30 years of age. Patients underwent standard evaluation, including radiography when indicated. At the point of final diagnosis and blinded to the NT-proBNP result, physicians documented the likelihood that heart failure accounted for the patient's acute dyspnea on a 7-point Likert scale, the data from which was subsequently collapsed to 3 categories for analysis purposes. The primary outcome was the agreement between clinical impression and the NT-proBNP assay classified using manufacturer-recommended, age-specific cut-offs. Newly proposed cut-offs from a recent study were also evaluated.

Results:

One hundred and twenty-nine patients making 139 ED visits were enrolled (median age 76 years; 59% admitted). The serum NT-proBNP assay was positive in 119 (86%, 95% confidence interval [CI] 80%–91%) cases, including 75% (43/57, 95% CI 62%–86%) of the cases that the treating physician felt were not caused by heart failure, and 86% (25/29, 95% CI 68%–96%) where the treating physician was unsure. The median NT-proBNP concentration was higher in patients clinically believed to have heart failure rather than pneumonia or chronic obstructive pulmonary disease; however, the ranges of these values overlapped extensively (median 4361 pg/mL; interquartile range [IQR] 2386–10877 v. 1651 pg/mL; IQR 370–4745, respectively).

Conclusions:

There is high discordance between the clinical impression of treating physicians and NT-proBNP concentrations, notably in patients who are believed not to have heart failure. Although the reference standard of ED diagnosis is imperfect, the broad overlap in NT-proBNP concentrations suggests poor specificity in this target patient population. The introduction of routine ED NT-proBNP testing using the current cut-offs would be expected to result in substantial indirect costs from further diagnostic testing. It remains unclear whether the introduction of this diagnostic test would have a positive impact on clinically relevant patient outcomes.

Lung ultrasound in heart failure: Lessons from re-analysis of Lung Ultrasound 2011 database

Introduction: In the setting of patients presenting with shortness of breath to an Emergency Department a simple lung ultrasound protocol aimed at detecting pulmonary oedema has been shown to have diagnostic accuracy of 85%. This article reviews data from the original study, in an attempt to determine whether adjusting the protocol and/or interpretive criteria would improve results. Method: A large lung ultrasound project provided the dataset. Inter-rater and intertest discrepancies were reviewed. Then original stored images and comments were retrospectively analysed using alternate interpretive criteria. Specific variations included changing the number of B-lines required to define 'wet lung' and assessing other pleural line abnormalities. Where they had been acquired cardiac loops were reviewed in addition to the lung images. Results: The 204 original studies available were reviewed. Some disagreement could be attributed to inexperience and unclear definitions. Adjusting the number of B-lines did not improve diagnostic accuracy. All positive scans, with numerous B-lines were reviewed using more advanced diagnostic criteria (pleural line abnormalities) and the number of false positives was decreased. In cases where cardiac views were available, their inclusion was beneficial. Conclusion: A simple lung ultrasound protocol to assess for 'wet lung' in patients presenting to Emergency Departments provides diagnostic accuracy of around 85% in the hands of relative novices. More advanced interpretation of the same_ultrasound images, and the addition of cardiac views, is likely to further improve diagnostic accuracy.

How to Improve Time to Diagnosis in Acute Heart Failure - Clinical Signs and Chest X-ray

Acute heart failure (AHF) is a leading cause of hospitalisation in developed nations with stubbornly poor outcomes in both the short and long term. Furthermore, alongside an ageing population the incidence continues to increase. Contemporary practice guidelines accordingly emphasise the importance of early recognition of heart failure in the acute setting to facilitate the timely instigation of key investigations, appropriate management and access to specialist care; all of which improve outcome. However, the diagnosis of AHF is often challenging, with no gold standard diagnostic test and presenting clinical features that may be non-specific, particularly in the elderly where they may be atypical, or masked by co-morbidity. This short review explores the main clinical signs and radiographic changes in patients with AHF relevant to clinical practice in accordance with the best available evidence.

Troponins in heart failure

The signs and symptoms of heart failure are frequently unspecific and correlate poorly with objective indices of cardiac function. Objective assessment of cardiac function by echocardiography or other imaging modalities also correlate poorly with symptomatic status and functional capacity. Accordingly, there is a need for circulating biomarkers that can provide incremental diagnostic and prognostic information to the existing armamentarium of tests. The introduction of more sensitive assays that allow determination of very low circulating concentrations of the myofibrillar proteins cardiac troponin I and T has not only resulted in improved diagnostic accuracy in the setting of acute coronary syndromes. The high sensitivity assays have also shown that cardiac troponins are frequently found chronically circulating in a variety of acute and chronic, cardiac and non-cardiac disease conditions, including acute heart failure and chronic symptomatic and asymptomatic left ventricular dysfunction. Cardiac troponin I and T provide may provide clinically useful prognostic information both concerning the future risk of developing heart failure in asymptomatic subjects and the risk of fatal events and hospital admissions in those with already established heart failure This review summarizes current literature on the clinical performance and utility of cardiac troponin measurements as diagnostic and prognostic tools in patients with symptomatic heart failure, as well as in those with asymptomatic left ventricular dysfunction, and clinical phenotypes at high risk for developing heart failure, including stable coronary artery disease, left ventricular hypertrophy, and aortic stenosis.

Point-of-care ultrasonography for the diagnosis of acute cardiogenic pulmonary edema in patients presenting with acute dyspnea: a systematic review and meta-analysis

OBJECTIVES

Acute dyspnea is a common presenting complaint to the emergency department (ED), and point-of-care (POC) lung ultrasound (US) has shown promise as a diagnostic tool in this setting. The primary objective of this systematic review was to determine the sensitivity and specificity of US using B-lines in diagnosing acute cardiogenic pulmonary edema (ACPE) in patients presenting to the ED with acute dyspnea.

METHODS

A systematic review protocol adhering to Cochrane Handbook guidelines was created to guide the search and analysis, and we searched the following databases: PubMed, EMBASE, Ovid MEDLINE, Ovid MEDLINE In-Process & Other Non-Indexed Citations, and the Cochrane Database of Systematic Reviews. References of reviewed articles were hand-searched, and electronic searches of conference abstracts from major emergency medicine, cardiology, and critical care conferences were conducted. The authors included prospective cohort and prospective case-control studies that recruited patients presenting to hospital with symptomatic, acute dyspnea, or where there was a clinical suspicion of congestive heart failure, and reported the sensitivity and specificity of B-lines in diagnosing ACPE. Studies of asymptomatic individuals or in patients where there was no suspicion of ACPE were excluded. The outcome of interest was a diagnosis of ACPE using US B-lines. A final diagnosis from clinical follow-up was accepted as the reference standard. Two reviewers independently reviewed all citations to assess for inclusion, abstracted data, and assessed included studies for methodologic quality using the QUADAS-2 tool. Contingency tables were used to calculate sensitivity and specificity. Three subgroup analyses were planned a priori to examine the effects of the type of study, patient population, and lung US protocol employed.

RESULTS

Seven articles (n = 1,075) were identified that met inclusion criteria (two studies completed in the ED, two in the intensive care unit [ICU], two on inpatient wards, and one in the prehospital setting). The seven studies were rated as average to excellent methodologic quality. The sensitivity of US using B-lines to diagnosis ACPE is 94.1% (95% confidence interval [CI] = 81.3% to 98.3%) and the specificity is 92.4% (95% CI = 84.2% to 96.4%). Preplanned subgroup analyses did not reveal statistically significant changes in the overall summary estimates, nor did exclusion of three potential outlier studies.

CONCLUSIONS

This study suggests that in patients with a moderate to high pretest probability for ACPE, an US study showing B-lines can be used to strengthen an emergency physician's working diagnosis of ACPE. In patients with a low pretest probability for ACPE, a negative US study can almost exclude the possibility of ACPE. Further studies including large numbers of ED patients presenting with undifferentiated dyspnea are required to gain more valid and reliable estimates of test accuracy in ED patients.

Standardized evaluation of lung congestion during COPD exacerbation better identifies patients at risk of dying

Background

Congestive heart failure is underdiagnosed in patients with chronic obstructive pulmonary disease (COPD). Pulmonary congestion on chest radiograph at admission for acute exacerbation of COPD (AECOPD) is associated with an increased risk of mortality. A standardized evaluation of chest radiographs may enhance prognostic accuracy.

Purpose

We aimed to evaluate whether a standardized, liberal assessment of pulmonary congestion is superior to the routine assessment in identifying patients at increased risk of long-term mortality, and to investigate the association of heart failure with N-terminal prohormone of brain natriuretic peptide (NT-proBNP) concentrations.

Material and methods

This was a prospective cohort study of 99 patients admitted for AECOPD. Chest radiographs obtained on admission were routinely evaluated and then later evaluated by blinded investigators using a standardized protocol looking for Kerley B lines, enlarged vessels in the lung apex, perihilar cuffing, peribronchial haze, and interstitial or alveolar edema, defining the presence of pulmonary congestion. Adjusted associations with long-term mortality and NT-proBNP concentration were calculated.

Results

The standardized assessment was positive for pulmonary congestion in 32 of the 195 radiographs (16%) ruled negative in the routine assessment. The standardized assessment was superior in predicting death during a median follow up of 1.9 years (P=0.022), and in multivariable analysis, only the standardized assessment showed a significant association with mortality (hazard ratio 2.4, 95% confidence interval [CI] 1.2–4.7) (P=0.016) and NT-proBNP (relative concentration 1.8, CI 1.2–2.6) (P=0.003).

Conclusion

By applying a standardized approach when evaluating pulmonary congestion on chest radiographs during AECOPD, a group of patients with increased risk of dying, possibly due to heart failure, is identified.

Comparison of a basic lung scanning protocol against formally reported chest x-ray in the diagnosis of pulmonary oedema

Introduction: Brief lung scan protocols have been recommended as a useful adjunct to identify pulmonary oedema in the breathless elderly patient. Some papers quote diagnostic accuracies above that of chest x-ray. Method: We recruited a prospective convenience sample of patients over sixty years of age reporting any breathlessness on presentation to the emergency department. Those who received both bedside lung scan and chest x-ray later had their case notes audited by an expert cardiologist for the cause of their breathlessness at presentation. Admission diagnosis was also extracted. Results: 204 comparative data sets were collected. Compared with cardiologist chart review, delayed expert radiology report had a diagnostic accuracy of 92.2% (95%CI 87.6 to 95.1). Bedside interpretation of lung scan protocol had a diagnostic accuracy of 85.3% (95%CI 79.8 to 89.5). The difference of 6.9% between the two accuracy measures was significant (95%CI 0.69 to 13.1). Admission diagnosis accuracy, which encompasses inexpert x-ray interpretation was 70.2%(95%CI 62.9 to 76.6), significantly less than either lung scan or expert chest x-ray report. Conclusion: For identifying heart failure in breathless patients, urgent chest x-ray with delayed formal report has not been shown to be redundant. Basic lung scan protocols should not yet replace chest x-ray, but may be more reliable in the interim than inexpert clinician interpretation of chest x-rays.

Rapid evaluation by lung-cardiac-inferior vena cava (LCI) integrated ultrasound for differentiating heart failure from pulmonary disease as the cause of acute dyspnea in the emergency setting

Background

Rapid and accurate diagnosis and management can be lifesaving for patients with acute dyspnea. However, making a differential diagnosis and selecting early treatment for patients with acute dyspnea in the emergency setting is a clinical challenge that requires complex decision-making in order to achieve hemodynamic balance, improve functional capacity, and decrease mortality. In the present study, we examined the screening potential of rapid evaluation by lung-cardiac-inferior vena cava (LCI) integrated ultrasound for differentiating acute heart failure syndromes (AHFS) from primary pulmonary disease in patients with acute dyspnea in the emergency setting.

Methods

Between March 2011 and March 2012, 90 consecutive patients (45 women, 78.1 ± 9.9 years) admitted to the emergency room of our hospital for acute dyspnea were enrolled. Within 30 minutes of admission, all patients underwent conventional physical examination, rapid ultrasound (lung-cardiac-inferior vena cava [LCI] integrated ultrasound) examination with a hand-held device, routine laboratory tests, measurement of brain natriuretic peptide, and chest X-ray in the emergency room.

Results

The final diagnosis was acute dyspnea due to AHFS in 53 patients, acute dyspnea due to pulmonary disease despite a history of heart failure in 18 patients, and acute dyspnea due to pulmonary disease in 19 patients. Lung ultrasound alone showed a sensitivity, specificity, negative predictive value, and positive predictive value of 96.2, 54.0, 90.9, and 75.0%, respectively, for differentiating AHFS from pulmonary disease. On the other hand, LCI integrated ultrasound had a sensitivity, specificity, negative predictive value, and positive predictive value of 94.3, 91.9, 91.9, and 94.3%, respectively.

Conclusions

Our study demonstrated that rapid evaluation by LCI integrated ultrasound is extremely accurate for differentiating acute dyspnea due to AHFS from that caused by primary pulmonary disease in the emergency setting.

The V-line: a sonographic aid for the confirmation of pleural fluid

BACKGROUND

Ultrasound is being used increasingly to diagnose pathological free fluid accumulation at the bedside. In addition to the detection of peritoneal and pericardial fluid, point-of-care ultrasound allows rapid bedside diagnosis of pleural fluid.

FINDINGS

In this short report, we describe the sonographic observation of the vertebral or 'V-line' to help confirm the presence of pleural fluid in the supine patient. The V-line sign is a result of the fluid acting as an acoustic window to enable visualization of vertebral bodies and posterior thoracic wall, thus confirming the presence of pleural fluid.

CONCLUSIONS

The V-line is a useful sonographic sign to aid the diagnosis of pleural free fluid.

Ultrasound pleural effusion sign as a useful marker for identifying heart failure worsening in established heart failure patients during follow-up

Clinical significance of UltraSound Pleural Effusion (US-PLE) and test characteristics of this sign for identifying worsening heart failure (HF) during follow-up of HF patients are unclear. Clinical records of 83 established HF patients were examined. The diagnosis of worsening HF was classified as "highly certain,""probable,""uncertain," or "no" based on the combination of the changes in symptoms/signs and B-type natriuretic peptide (BNP). Routine test included searching for the US-PLE sign. During a follow-up of 652±456 days, 1826 visits were evaluated. Among the 83 study patients, 78 had at least one of the following: worsening symptom(s), HF-related sign(s), and/or elevated BNP levels (≥3-fold increase) at one or more clinic visits. The US-PLE sign was present at 83 visits of 49 study patients. Its appearance was associated with the presence of HF-related symptom(s)/sign(s) and BNP elevation (odds ratio, 53-177, P<.0001 each). The test characteristics of the US-PLE sign for diagnosis of high possibility of worsening HF status fulfilling the "highly certain" or "probable" criteria were: sensitivity (76.6%), specificity (98.6%), positive predictive value (71.1%), and negative predictive value (99.0%). The US-PLE sign has high diagnostic accuracy for identifying worsening HF, including asymptomatic events, in HF patients during follow-up.

Diagnostic accuracy and reproducibility of pleural and lung ultrasound in discriminating cardiogenic causes of acute dyspnea in the emergency department

Dyspnea is a common symptom in patients admitted to the Emergency Department (ED), and discriminating between cardiogenic and non-cardiogenic dyspnea is often a clinical dilemma. The initial diagnostic work-up may be inaccurate in defining the etiology and the underlying pathophysiology. The aim of this study was to evaluate the diagnostic accuracy and reproducibility of pleural and lung ultrasound (PLUS), performed by emergency physicians at the time of a patient's initial evaluation in the ED, in identifying cardiac causes of acute dyspnea. Between February and July 2007, 56 patients presenting to the ED with acute dyspnea were prospectively enrolled in this study. In all patients, PLUS was performed by emergency physicians with the purpose of identifying the presence of diffuse alveolar-interstitial syndrome (AIS) or pleural effusion. All scans were later reviewed by two other emergency physicians, expert in PLUS and blinded to clinical parameters, who were the ultimate judges of positivity for diffuse AIS and pleural effusion. A random set of 80 recorded scannings were also reviewed by two inexperienced observers to assess inter-observer variability. The entire medical record was independently reviewed by two expert physicians (an emergency medicine physician and a cardiologist) blinded to the ultrasound (US) results, in order to determine whether, for each patient, dyspnea was due to heart failure, or not. Sensitivity, specificity, and positive/negative predictive values were obtained; likelihood ratio (LR) test was used. Cohen's kappa was used to assess inter-observer agreement. The presence of diffuse AIS was highly predictive for cardiogenic dyspnea (sensitivity 93.6%, specificity 84%, positive predictive value 87.9%, negative predictive value 91.3%). On the contrary, US detection of pleural effusion was not helpful in the differential diagnosis (sensitivity 83.9%, specificity 52%, positive predictive value 68.4%, negative predictive value 72.2%). Finally, the coexistence of diffuse AIS and pleural effusion is less accurate than diffuse AIS alone for cardiogenic dyspnea (sensitivity 81.5%, specificity 82.8%, positive predictive value 81.5%, negative predictive value 82.8%). The positive LR was 5.8 for AIS [95% confidence interval (CI) 4.8-7.1] and 1.7 (95% CI 1.2-2.6) for pleural effusion, negative LR resulted 0.1 (95% CI 0.0-0.4) for AIS and 0.3 (95% CI 0.1-0.8) for pleural effusion. Agreement between experienced and inexperienced operators was 92.2% (p < 0.01) and 95% (p < 0.01) for diagnosis of AIS and pleural effusion, respectively. In early evaluation of patients presenting to the ED with dyspnea, PLUS, performed with the purpose of identifying diffuse AIS, may represent an accurate and reproducible bedside tool in discriminating between cardiogenic and non-cardiogenic dyspnea. On the contrary, US detection of pleural effusions does not allow reliable discrimination between different causes of acute dyspnea in unselected ED patients.

Contribution of extracardiac factors to the inconsistency between plasma B-type natriuretic peptide levels and the severity of pulmonary congestion on chest X-rays in the diagnosis of heart failure

OBJECTIVE

Chest X-rays and plasma B-type natriuretic peptide (BNP) levels are useful for diagnosing congestive heart failure. However, the relationship between plasma BNP levels and pulmonary congestion on chest X-rays often seems inconsistent. Extracardiac factors can directly alter plasma BNP levels, independent of cardiac function. In the present study, we examined the clinical factors that impact the diagnosis of heart failure by using chest X-rays and plasma BNP levels.

METHODS AND RESULTS

This study comprised 459 consecutive patients who were admitted to the cardiovascular division of our hospital for any reason and in whom chest X-rays and plasma BNP levels were measured within 12 hours after admission. The approximate BNP value associated with pulmonary congestion that was detectable by chest X-rays was 143 pg/mL, but this value was influenced by renal function, age, and body mass index (BMI). Furthermore, we examined the effect of these three extracardiac factors on plasma BNP levels in each stage of pulmonary congestion. We found that renal dysfunction and advanced age increased the plasma BNP levels, whereas a high BMI decreased the levels, and that the effect of BMI on plasma BNP levels was greater for severe heart failure.

CONCLUSION

Extracardiac factors should be considered when the relationship between the plasma BNP levels and the severity of pulmonary congestion on chest X-rays seems inconsistent. In particular, low levels of plasma BNP in patients with a high BMI should be carefully considered to avoid underestimating the degree of heart failure.

Thoracic ultrasonography: A new method for the work-up of patients with dyspnea()

OBJECTIVE

Differential diagnosis of dyspnea is vital for the management of respiratory failure, where routine parameters can now be integrated with thoracic ultrasound data. The objective of this study was to evaluate the validity and accuracy of this approach in a department of internal medicine.

MATERIALS AND METHODS

We enrolled 152 patients consecutively hospitalized with a diagnosis of dyspnea. After clinical evaluation, chest radiography, biochemical assays (NT-proBNP), and emergency treatment, patients underwent ultrasound examination of the lungs. Results were considered positive if the total number of lines B was higher than 8. The ultrasound examination and NT-proBNP assay were repeated after 48 h. The gold standard was the clinical diagnosis of heart failure made by medical experts in accordance with AHA guidelines.

RESULTS

The group of patients with positive ultrasound findings had a higher frequency of heart failure diagnoses (X(2) 92.5, p < 0.005) and significantly higher values of NT-proBNP (10,384 ng/l vs 3889 ng/l, p < 0.05). Moreover, the decrease in the number of B lines at 48 h was significantly greater (p < 0.005) among patients treated for heart failure. There were no significant changes in the values of NT-proBNP (p = 0.37).

DISCUSSION

In conclusion we have shown that even in a department of internal medicine, lung ultrasonography is a useful tool for diagnosing respiratory insufficiency and monitoring its response to therapy.

Inferior vena cava assessment in the bedside diagnosis of acute heart failure

OBJECTIVES

The objective of this study was to determine the test characteristics of the caval index and caval-aortic ratio in predicting the diagnosis of acute heart failure in patients with undifferentiated dyspnea in the emergency department (ED).

METHODS

This prospective observational study was performed at an urban ED that enrolled patients, 50 years or older, with acute dyspnea. A sonographic caval index was calculated as the percentage decrease in the inferior vena cava (IVC) diameter during respiration. A caval-aortic ratio was defined by the maximum IVC diameter divided by the aortic diameter. The sensitivity, specificity, and likelihood ratios of these measurements associated with heart failure were estimated.

RESULTS

Eighty-nine patients were enrolled in the study with a mean age of 68 years. A caval index of less than 33% had 80% sensitivity (95% confidence interval [CI], 63%-91%) and 81% specificity (95% CI, 68%-90%) in diagnosing acute heart failure, whereas an index of less than 15% had a 37% sensitivity (95% CI, 22%-55%) and 96% specificity (95% CI, 86%-99%). The sensitivity of a caval-aortic ratio of more than 1.2 was 33% (95% CI, 18%-52%) and the specificity was 96% (95% CI, 86%-99%). Positive likelihood ratios were 10 for a caval index of less than 15%, 4.3 for an index of less than 33%, and 8.3 for a caval-aortic ratio of more than 1.2.

CONCLUSION

Bedside assessments of the caval index or caval-aortic ratio may be useful clinical adjuncts in establishing the diagnosis of acute heart failure in patients with undifferentiated dyspnea.

The use of capnometry to predict arterial partial pressure of CO(2) in non-intubated breathless patients in the emergency department

Background

Capnometry measures carbon dioxide in expired air and provides the clinician with a noninvasive measure of the systemic metabolism, circulation and ventilation. This study was carried out on patients with acute breathlessness to define the utility and role of capnometry in the emergency department.

Aim

The objectives of the study were:

To determine the correlation between end tidal CO₂ and PaCO₂ in non-intubated acutely breathless patients.

To determine factors that influence the end tidal carbon dioxide (ETCO₂).

To determine the correlation between ETCO₂ with PaCO₂ in patients presenting with pulmonary disorders.

Methods

One hundred fifty acutely breathless patients arriving at the emergency department and fulfilling the inclusion and exclusion criteria were chosen during a 6-month study period. The patients gave written or verbal consent, and were triaged and treated according to their presenting complaints. Demographic data were collected, and the ETCO₂ data were recorded. Arterial blood gas was taken in all patients. The data were compiled and analyzed using various descriptive studies from the Statistics Program for Social Studies (SPSS) version 12. Correlation between ETCO₂ and PaCO₂ was analyzed using the Pearson correlation coefficient. Other variables also were analyzed to determine the correlation using simple linear regression. The agreement and difference between ETCO₂ and PaCO₂ were analyzed using paired sample t-tests.

Results

There is a strong correlation between ETCO₂ and PaCO₂ using the Pearson correlation coefficient: 0.716 and p value of 0.00 (p < 0.05). However, the paired t-test showed a mean difference between the two parameters of 4.303 with a p value < 0.05 (95% CI 2.818, 5.878). There was also a good correlation between ETCO₂ and acidosis state with a Pearson correlation coefficient of 0.374 and p value 0.02 (p < 0.05). A strong correlation was also observed between ETCO₂ and a hypocapnic state, with a Pearson correlation coefficient of 0.738 (p < 0.05). Weak correlation was observed between alkalosis and ETCO₂, with a Pearson correlation coefficient of 0.171 (p < 0.05). A strong negative correlation was present between ETCO₂ and hypercapnic patients presenting with pulmonary disorders, with a Pearson correlation coefficient of -0.738 (p < 0.05) and of -0.336 (p < 0.05), respectively.

Conclusion

This study shows that ETCO₂ can be used to predict the PaCO₂ level when the difference between the PaCO₂ and ETCO₂ is between 2 to 6 mmHg, especially in cases of pure acidosis and hypocapnia. Using ETCO₂ to predict PaCO₂ should be done with caution, especially in cases that involve pulmonary disorders and acid-base imbalance.

Jugular venous distension on ultrasound: sensitivity and specificity for heart failure in patients with dyspnea

BACKGROUND

Accurately diagnosing congestive heart failure (CHF) in patients with dyspnea can be difficult because clinical history and physical examination are often nondiagnostic and may be inaccurate, especially when patients have complicated comorbid conditions.

OBJECTIVE

To prospectively assess jugular venous distension on ultrasound (JVD-US) performed by emergency physicians for identifying CHF on echocardiography by the department of cardiology (C-ECHO) in patients with dyspnea.

MEASUREMENTS

This was a secondary analysis of a previously collected data set from a prospective study of JVD-US in ED patients with dyspnea due to suspected CHF. C-ECHO results were obtained and used as the criterion standard.

RESULTS

Jugular venous distension on ultrasound had a sensitivity of 99% (95% confidence interval [CI], 92.2%-100%), specificity of 59% (95% CI, 40.9%-74.4%), positive likelihood ratio of 2.4 (95% CI, 1.6-3.6), and negative likelihood ratio of 0.01 (95% CI, 0.0007-0.20) for identifying CHF on C-ECHO in patients with dyspnea.

CONCLUSION

This initial study suggests that JVD-US by emergency physicians is predictive of CHF using echocardiography performed by the department of cardiology as the criterion standard.

Utility of daily diuretic orders for identifying acute decompensated heart failure patients for quality improvement

INTRODUCTION

Many studies have demonstrated gaps in adherence to American College of Cardiology (ACC)/American Heart Association (AHA) guidelines among patients with acute decompensated heart failure (ADHF). Quality improvement initiatives can improve compliance with guideline-recommended therapy yet a major challenge to such programs is identifying heart failure patients across the many wards and services of the complex hospital environment.

METHODS AND RESULTS

Using our hospital's electronic order-entry system, we generated a daily list of all hospitalized patients receiving a loop diuretic. Over a 3-month period, each patient on this list was screened through chart review for a diagnosis of ADHF. For those patients with ADHF, a clinical reminder about ACC/AHA recommended therapies was placed in the chart. Patient outcomes were followed using the Get With The Guidelines heart failure database.During the study period, 98.6% of patients with ADHF were identified by the diuretics list. The diuretics list had a sensitivity of 98.6% and specificity of 92.2%. The diuretic list captured more ADHF patients than alternative methods such as chest x-ray and brain natriuretic peptide level. Use of the daily diuretic list and targeted reminders to clinicians was associated with an improvement in recommended therapies including smoking-cessation education and heart failure teaching.

CONCLUSIONS

A daily list of inpatients receiving diuretics allowed real-time identification of most hospitalized heart failure patients at our institution. Targeted reminders to clinicians regarding ACC/AHA-recommended therapies for heart failure were associated with improvements in guideline adherence.

Lung ultrasound: a new tool for the emergency physician

Patients with dyspnea are routinely assessed with physical examination, lung auscultation and chest X-rays. Auscultation and bedside radiography have a low accuracy in the critically ill. Chest X-ray images remain suboptimal in more than one-third of cases and are poorly correlated to lung CT images. Lung ultrasound is invaluable as a bedside diagnostic tool of the dyspneic patient since, in a few minutes, it may help distinguish the typical features of most common causes of dyspnea. The lung has been improperly considered to be poorly accessible using ultrasound, because air prevents the progression of the ultrasound beam with production of reverberation artifacts under the lung surface. This article reviews the scanning technique, and the normal and pathological findings of lung ultrasound, and underscores its utility in providing the emergency physician with a new, fast and reliable diagnostic tool.