How well can the chest radiograph diagnose left ventricular dysfunction?

Heart Failure With Improved Ejection Fraction: Prevalence, Predictors, and Guideline-Directed Medical Therapy

Recently, a new category of heart failure with improved ejection fraction (HFimpEF) has emerged in the classification system. This is defined as the subgroup of patients with heart failure with reduced ejection fraction (HFrEF) whose left ventricular ejection fraction has recovered partially or completely, with no specific cut-off values established yet in the guidelines. In our review, we aim to provide an overview of prevalence, predictors, mechanism of remodeling, and management strategies regarding HFimpEF. These patients constitute a sizeable cohort among patients with reduced ejection fraction. Certain patient characteristics including younger age and female gender, absence of comorbid conditions, low levels of biomarkers, and non-ischemic etiology were identified as positive predictors. The heart undergoes significant maladaptive changes post failure leading to adverse remodeling influenced etiology and duration. Goal-directed medical therapy including beta-blockers, angiotensin-converting enzyme inhibitors (ACEIs), and angiotensin II receptor blockers (ARBs) have notably improved cardiac function by inducing reverse remodeling. Despite a more favorable prognosis compared to HFrEF, patients with improved ejection fraction (EF) still face clinical events and reduced quality of life, and remain at risk of adverse outcomes. Although the evidence is scarce, it is advisable to continue treatment modalities despite improvement in EF, including device therapies, to prevent relapse and clinical deterioration. It is imperative to conduct further research to understand the mechanism leading to EF amelioration and establish guidelines to identify and direct management strategies.

Artificial intelligence-based model to classify cardiac functions from chest radiographs: a multi-institutional, retrospective model development and validation study

BACKGROUND

Chest radiography is a common and widely available examination. Although cardiovascular structures-such as cardiac shadows and vessels-are visible on chest radiographs, the ability of these radiographs to estimate cardiac function and valvular disease is poorly understood. Using datasets from multiple institutions, we aimed to develop and validate a deep-learning model to simultaneously detect valvular disease and cardiac functions from chest radiographs.

METHODS

In this model development and validation study, we trained, validated, and externally tested a deep learning-based model to classify left ventricular ejection fraction, tricuspid regurgitant velocity, mitral regurgitation, aortic stenosis, aortic regurgitation, mitral stenosis, tricuspid regurgitation, pulmonary regurgitation, and inferior vena cava dilation from chest radiographs. The chest radiographs and associated echocardiograms were collected from four institutions between April 1, 2013, and Dec 31, 2021: we used data from three sites (Osaka Metropolitan University Hospital, Osaka, Japan; Habikino Medical Center, Habikino, Japan; and Morimoto Hospital, Osaka, Japan) for training, validation, and internal testing, and data from one site (Kashiwara Municipal Hospital, Kashiwara, Japan) for external testing. We evaluated the area under the receiver operating characteristic curve (AUC), sensitivity, specificity, and accuracy.

FINDINGS

We included 22 551 radiographs associated with 22 551 echocardiograms obtained from 16 946 patients. The external test dataset featured 3311 radiographs from 2617 patients with a mean age of 72 years [SD 15], of whom 49·8% were male and 50·2% were female. The AUCs, accuracy, sensitivity, and specificity for this dataset were 0·92 (95% CI 0·90-0·95), 86% (85-87), 82% (75-87), and 86% (85-88) for classifying the left ventricular ejection fraction at a 40% cutoff, 0·85 (0·83-0·87), 75% (73-76), 83% (80-87), and 73% (71-75) for classifying the tricuspid regurgitant velocity at a 2·8 m/s cutoff, 0·89 (0·86-0·92), 85% (84-86), 82% (76-87), and 85% (84-86) for classifying mitral regurgitation at the none-mild versus moderate-severe cutoff, 0·83 (0·78-0·88), 73% (71-74), 79% (69-87), and 72% (71-74) for classifying aortic stenosis, 0·83 (0·79-0·87), 68% (67-70), 88% (81-92), and 67% (66-69) for classifying aortic regurgitation, 0·86 (0·67-1·00), 90% (89-91), 83% (36-100), and 90% (89-91) for classifying mitral stenosis, 0·92 (0·89-0·94), 83% (82-85), 87% (83-91), and 83% (82-84) for classifying tricuspid regurgitation, 0·86 (0·82-0·90), 69% (68-71), 91% (84-95), and 68% (67-70) for classifying pulmonary regurgitation, and 0·85 (0·81-0·89), 86% (85-88), 73% (65-81), and 87% (86-88) for classifying inferior vena cava dilation.

INTERPRETATION

The deep learning-based model can accurately classify cardiac functions and valvular heart diseases using information from digital chest radiographs. This model can classify values typically obtained from echocardiography in a fraction of the time, with low system requirements and the potential to be continuously available in areas where echocardiography specialists are scarce or absent.

FUNDING

None.

Dual Specific Phosphatase 7 Exacerbates Dilated Cardiomyopathy, Heart Failure, and Cardiac Death by Inactivating the ERK1/2 Signaling Pathway

Heart failure is one of the most common but complicated end-stage syndromes in clinical practice. Dilated cardiomyopathy is a myocardial structural abnormality that is associated with heart failure. Dual-specificity phosphatases (DUSPs) are a group of protein phosphatases that regulate signaling pathways in numerous diseases; however, their physiological and pathological impact on cardiovascular disease remains unknown. In the present study, we generated two transgenic mouse models, a DUSP7 knockout and a cardiac-specific DUSP7 overexpressor. Mice overexpressing DUSP7 showed an exacerbated disease phenotype, including severe dilated cardiomyopathy, heart failure, and cardiac death. We further demonstrated that high levels of DUSP7 inhibited ERK1/2 phosphorylation and influenced downstream c-MYC, c-FOS, and c-JUN gene expression but did not affect upstream activators. Taken together, our study reveals a novel molecular mechanism for DUSP7 and provides a new therapeutic target and clinical path to alleviate dilated cardiomyopathy and improve cardiac function.

Heart Failure: An Underappreciated Complication of Diabetes. A Consensus Report of the American Diabetes Association

Heart failure (HF) has been recognized as a common complication of diabetes, with a prevalence of up to 22% in individuals with diabetes and increasing incidence rates. Data also suggest that HF may develop in individuals with diabetes even in the absence of hypertension, coronary heart disease, or valvular heart disease and, as such, represents a major cardiovascular complication in this vulnerable population; HF may also be the first presentation of cardiovascular disease in many individuals with diabetes. Given that during the past decade, the prevalence of diabetes (particularly type 2 diabetes) has risen by 30% globally (with prevalence expected to increase further), the burden of HF on the health care system will continue to rise. The scope of this American Diabetes Association consensus report with designated representation from the American College of Cardiology is to provide clear guidance to practitioners on the best approaches for screening and diagnosing HF in individuals with diabetes or prediabetes, with the goal to ensure access to optimal, evidence-based management for all and to mitigate the risks of serious complications, leveraging prior policy statements by the American College of Cardiology and American Heart Association.

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.

Prediction of Judkins Left Catheter Size during Left Transradial Coronary Angiography by Simple Chest Radiographic and Echocardiographic Index

Background and Objectives: Appropriate catheter selection when conducting transradial coronary angiography (CAG) helps shorten examination time, preventing vascular complications and lowering medical expense. However, catheter selection is made based on the practitioner’s experience in almost all cases. Therefore, we undertook this study to define radiologic and echocardiographic indices that would enable physicians to anticipate appropriate catheter selection. Materials and Methods: This is a retrospective study of 244 undergoing transradial diagnostic CAG at an established center from February 2006 to April 2014. Patients who successfully underwent angiography with a JL3.5 catheter were defined as the control group, and patients who successfully underwent angiography after the catheter was replaced with a JL4.0 or higher were defined as the switched group. To identify predictors for appropriate catheter selection, radiologic and echocardiographic indices were analyzed. Results: A total of 122 patients in the switched group and 122 patients in the control group were analyzed in this study. Average age was 64.65 ± 8.6 years. In the radiographic index, the switched group exhibited a significantly higher mediastinal-thoracic ratio (0.27 ± 0.05 vs. 0.23 ± 0.03, p < 0.001. Additionally, the mediastinal-cardiac ratio was significantly greater in the switched group (0.50 ± 0.08 vs. 0.45 ± 0.05, p < 0.001). Aortic root diameter, which is used here as the echocardiographic index, was significantly larger in the switched group compared to the control group (34.94 ± 4.18 mm vs. 32.66 ± 3.99 mm, p < 0.001). In the multivariable logistic regression model, mediastinal-cardiac ratio (OR 5.197, 95% CI 2.608–10.355, p < 0.001) and increased aortic root (OR 2.115, 95% CI 1.144–3.912, p = 0.017) were significantly associated with catheter change. Conclusions: Mediastinal-cardiac ratio and aortic root diameter provide helpful and effective indices for appropriate catheter selection during transradial coronary angiography.

The Contributing Risk of Tobacco Use for ARDS Development in Burn-Injured Adults With Inhalation Injury

BACKGROUND

This study aims to determine the relationship between tobacco use, inhalation injury, and ARDS in burn-injured adults.

METHODS

This study was an observational cohort of 2,485 primary burn admissions to a referral burn center between January 1, 2008 and March 15, 2015. Subjects were evaluated by methods used to account for mediation and traditional approaches (multivariable logistic regression and propensity score analysis). Mediation analysis examined both the (1) indirect effect of tobacco use via inhalation injury as the mediator on ARDS development and (2) the direct effect of tobacco use alone on ARDS development.

RESULTS

ARDS development occurred in 6.8% (n = 170) of the cohort. Inhalation injury occurred in 5.0% (n = 125) of the cohort, and ARDS developed in 48.8% (n = 83) of the subjects with inhalation injury. Tobacco use was 2-fold more common in subjects with ARDS. In the mediated model, the direct effect of tobacco use on ARDS, including interaction between tobacco use and inhalation injury, was not significant (odds ratio [OR] 1.63, 95% CI 0.91-2.92, P = .10). However, the indirect effect of tobacco use via inhalation injury as the mediator was significant (OR 1.61, 95% CI 1.25-2.07, P < .001), and the proportion of the total effect of tobacco use operating through the mediator was 55.6%. In the non-mediation models (multivariable logistic regression and propensity score analysis), which controlled for inhalation injury and other covariables, the OR for the association between tobacco use and ARDS was 1.84 (95% CI 1.22-2.81, P < .001) and 1.69 (95% CI 1.04-2.75, P = .03), respectively.

CONCLUSIONS

In mediation analysis, inhalation injury was the overwhelming predictor for ARDS development, whereas tobacco use has its strongest effect indirectly through inhalation injury. Patients with at least moderate inhalation injury are at greatest risk for ARDS development despite baseline risk factors like tobacco use.

The Usefulness of the Delta Neutrophil Index for Predicting Superimposed Pneumonia in Patients with Acute Decompensated Heart Failure in the Emergency Department

Background

Although respiratory infections, such as pneumonia, have long been recognized as precipitators of exacerbation in patients with acute decompensated heart failure (ADHF), identifying signs of concomitant pneumonia in ADHF is a clinical diagnostic challenge. We evaluated the predictive value of the delta neutrophil index (DNI), a new indicator for immature granulocytes, for diagnosing superimposed pneumonia in patients presenting with ADHF in the emergency department (ED).

Methods

This was a retrospective and observational study of consecutive patients (>18 years old) diagnosed with an ADHF in the ED over a 7-month period. Patients were categorized into either the ADHF group or the ADHF with pneumonia group. DNI, serum white blood cell (WBC), C-reactive protein (CRP), and β-natriuretic peptide (BNP) were measured upon ED arrival.

Results

The ADHF with pneumonia group included 30 patients (20.4%). Median initial DNI, WBC, and CRP were significantly higher in the ADHF with pneumonia group [0% vs. 1.8%, p<0.001, 8,200 cells/mL vs. 10,470 cells/mL, p<0.001, and 0.56 mg/dL vs. 6.10 mg/dL, p<0.001]. Multiple logistic regression analyses showed that only initial DNI significantly predicted the presence of superimposed pneumonia in patients with ADHF. In the receiver operating characteristic curves for initial DNI, WBC, and CRP for differentiating superimposed pneumonia in ADHF patients, the area under curve (AUC) of DNI (0.916 [95% confidence interval 0.859–0.955]) was good. AUC of DNI was significantly higher than AUC of CRP and WBC [0.828 and 0.715] (DNI vs. CRP, p = 0.047 and DNI vs. WBC, p<0.001).

Conclusions

Initial DNI, which was measured upon ED arrival, was significantly higher in the ADHF with pneumonia group than in the ADHF group. The initial DNI’s ability of prediction for ADHF with superimposed pneumonia in the ED was good and it was better than those of serum WBC and CRP. Therefore, DNI may serve as a convenient and useful marker for early diagnosis of superimposed pneumonia in patients with ADHF in the ED.

Clinical features of heart failure and acute coronary syndromes

This article provides a brief overview of the clinical presentation, laboratory and radiologic features, and basic management principles in patients with congestive heart failure (CHF) and acute coronary syndromes (ACS). CHF is a clinical syndrome that typically results in symptoms of congestion and hypoperfusion. A thorough physical examination complemented by cardiac biomarkers and imaging are essential in making the diagnosis. Medical and device therapies for CHF target improvement in survival as well as control of symptoms. The management of ACS involves making a prompt diagnosis through the use of a focused history and physical examination, electrocardiogram assessment, and cardiac biomarker evaluation. Timely revascularization along with optimal medical management have helped to improve patient outcomes and mortality.

Incidental chest radiographic findings in adult patients with acute cough

PURPOSE

Imaging may produce unexpected or incidental findings with consequences for patients and ordering of future investigations. Chest radiography in patients with acute cough is among the most common reasons for imaging in primary care, but data on associated incidental findings are lacking. We set out to describe the type and prevalence of incidental chest radiography findings in primary care patients with acute cough.

METHODS

We report on data from a cross-sectional study in 16 European primary care networks on 3,105 patients with acute cough, all of whom were undergoing chest radiography as part of a research study workup. Apart from assessment for specified signs of pneumonia and acute bronchitis, local radiologists were asked to evaluate any additional finding on the radiographs. For the 2,823 participants with good-quality chest radiographs, these findings were categorized according to clinical relevance based on previous research evidence and analyzed for type and prevalence by network, sex, age, and smoking status.

RESULTS

Incidental findings were reported in 19% of all participants, and ranged from 0% to 25% by primary care network, with the network being an independent contributor (P <.001). Of all participants 3% had clinically relevant incidental findings. Suspected nodules and shadows were reported in 1.8%. Incidental findings were more common is older participants and smokers (P <. 001).

CONCLUSIONS

Clinically relevant incidental findings on chest radiographs in primary care adult patients with acute cough are uncommon, and prevalence varies by setting.

The REFER (REFer for EchocaRdiogram) protocol: a prospective validation of a clinical decision rule, NT-proBNP, or their combination, in the diagnosis of heart failure in primary care. Rationale and design

BACKGROUND

Heart failure is a major cause of mortality and morbidity. As mortality rates are high, it is important that patients seen by general practitioners with symptoms suggestive of heart failure are identified quickly and treated appropriately. Identifying patients with heart failure or deciding which patients need further tests is a challenge. All patients with suspected heart failure should be diagnosed using objective tests such as echocardiography, but it is expensive, often delayed, and limited by the significant skill shortage of trained echocardiographers. Alternative approaches for diagnosing heart failure are currently limited. Clinical decision tools that combine clinical signs, symptoms or patient characteristics are designed to be used to support clinical decision-making and validated according to strict methodological procedures. The REFER Study aims to determine the accuracy and cost-effectiveness of our previously derived novel, simple clinical decision rule, a natriuretic peptide assay, or their combination, in the triage for referral for echocardiography of symptomatic adult patients who present in general practice with symptoms suggestive of heart failure.

METHODS/DESIGN

This is a prospective, Phase II observational, diagnostic validation study of a clinical decision rule, natriuretic peptides or their combination, for diagnosing heart failure in primary care. Consecutive adult primary care patients 55 years of age or over presenting to their general practitioner with a chief complaint of recent new onset shortness of breath, lethargy or peripheral ankle oedema of over 48 hours duration, with no obvious recurrent, acute or self-limiting cause will be enrolled. Our reference standard is based upon a three step expert specialist consensus using echocardiography and clinical variables and tests.

DISCUSSION

Our clinical decision rule offers a potential solution to the diagnostic challenge of providing a timely and accurate diagnosis of heart failure in primary care. Study results will provide an evidence-base from which to develop heart failure care pathway recommendations and may be useful in standardising care. If demonstrated to be effective, the clinical decision rule will be of interest to researchers, policy makers and general practitioners worldwide.

TRIAL REGISTRATION

ISRCTN17635379.

The diagnostic value of physical examination and additional testing in primary care patients with suspected heart failure

BACKGROUND

Early diagnosis of nonacute heart failure is crucial because prompt initiation of evidence-based treatment can prevent or slow down further progression. To diagnose new-onset heart failure in primary care is challenging.

METHODS AND RESULTS

This is a cross-sectional diagnostic accuracy study with external validation. Seven hundred twenty-one consecutive patients suspected of new-onset heart failure underwent standardized diagnostic work-up including chest x-ray, spirometry, ECG, N-terminal pro-B-type natriuretic peptide (NT-proBNP) measurement, and echocardiography in specially equipped outpatient diagnostic heart failure clinics. The presence of heart failure was determined by an outcome panel using the initial clinical data and 6-month follow-up data, blinded to biomarker data. Of the 721 patients, 207 (28.7%) had heart failure. The combination of 3 items from history (age, coronary artery disease, and loop diuretic use) plus 6 from physical examination (pulse rate and regularity, displaced apex beat, rales, heart murmur, and increased jugular vein pressure) showed independent diagnostic value (c-statistic 0.83). NT-proBNP was the most powerful supplementary diagnostic test, increasing the c-statistic to 0.86 and resulting in net reclassification improvement of 69% (P<0.0001). A simplified diagnostic rule was applied to 2 external validation datasets, resulting in c- statistics of 0.95 and 0.88, confirming the results.

CONCLUSIONS

In this study, we estimated the quantitative diagnostic contribution of elements of the history and physical examination in the diagnosis of heart failure in primary care outpatients, which may help to improve clinical decision making. The largest additional quantitative diagnostic contribution to those elements was provided by measurement of NT-proBNP. For daily practice, a diagnostic rule was derived that may be useful to quantify the probability of heart failure in patients with new symptoms suggestive of heart failure.

Implantable hemodynamic monitors

The evaluation and management of volume status in patients with heart failure is a challenge for most clinicians. In addition, such an evaluation is possible only during a personal clinician-patient interface. The ability to acquire hemodynamic data continuously with the help of implanted devices with remote monitoring capability can provide early warning of heart failure decompensation and thus may aid in preventing hospitalizations for heart failure. The data obtained also may improve the understanding of the disease process. It is important for the clinician treating patients who have heart failure to become acquainted with this type of technology and learn to interpret and use these data appropriately. This article reviews the implantable hemodynamics monitors currently available.

Performance of an automated electronic acute lung injury screening system in intensive care unit patients

OBJECTIVE

Lung protective ventilation reduces mortality in patients with acute lung injury, but underrecognition of acute lung injury has limited its use. We recently validated an automated electronic acute lung injury surveillance system in patients with major trauma in a single intensive care unit. In this study, we assessed the system's performance as a prospective acute lung injury screening tool in a diverse population of intensive care unit patients.

DESIGN

Patients were screened prospectively for acute lung injury over 21 wks by the automated system and by an experienced research coordinator who manually screened subjects for enrollment in Acute Respiratory Distress Syndrome Clinical Trials Network (ARDSNet) trials. Performance of the automated system was assessed by comparing its results with the manual screening process. Discordant results were adjudicated blindly by two physician reviewers. In addition, a sensitivity analysis using a range of assumptions was conducted to better estimate the system's performance.

SETTING

The Hospital of the University of Pennsylvania, an academic medical center and ARDSNet center (1994-2006).

PATIENTS

Intubated patients in medical and surgical intensive care units.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of 1270 patients screened, 84 were identified with acute lung injury (incidence of 6.6%). The automated screening system had a sensitivity of 97.6% (95% confidence interval, 96.8-98.4%) and a specificity of 97.6% (95% confidence interval, 96.8-98.4%). The manual screening algorithm had a sensitivity of 57.1% (95% confidence interval, 54.5-59.8%) and a specificity of 99.7% (95% confidence interval, 99.4-100%). Sensitivity analysis demonstrated a range for sensitivity of 75.0-97.6% of the automated system under varying assumptions. Under all assumptions, the automated system demonstrated higher sensitivity than and comparable specificity to the manual screening method.

CONCLUSIONS

An automated electronic system identified patients with acute lung injury with high sensitivity and specificity in diverse intensive care units of a large academic medical center. Further studies are needed to evaluate the effect of automated prompts that such a system can initiate on the use of lung protective ventilation in patients with acute lung injury.

National Heart, Lung, and Blood Institute working group on emergency department management of acute heart failure: research challenges and opportunities

This paper details the substance and recommendations arising from a meeting convened by the National Heart, Lung, and Blood Institute in August 2009, to assess the challenges and opportunities of emergency department management of acute heart failure syndrome (AHFS). The assembled faculty represented a large cross section of medical professionals spanning the medical management continuum of patients presenting with acute heart failure and included heart failure cardiologists, emergency physicians, laboratory medicine specialists, nurses, and bench scientists. Their recommendations include proposals regarding the design and conduct of emergency department-based clinical trials, suggestions regarding the development of improved methods for early detection and monitoring of AHFS, and potential needs for expanding translational and applied AHFS focused research and biotechnology. We anticipate that this review will serve as a starting point for future investigations across the spectrum of funding sources.

Using Impedance Cardiography to Assess Left Ventricular Systolic Function via Postural Change in Patients With Heart Failure

For the diagnosis and management of heart failure, it would be useful to have a simple point-of-care test for assessing ventricular function that could be performed by a nurse. An impedance cardiography (ICG) parameter called systolic amplitude (SA) can serve as an indicator of left ventricular systolic function (LVSF). This study tested the hypothesis that patients with normal LVSF should have a significant increase in SA in response to an increase in end-diastolic volume caused by postural change from sitting upright to supine, while patients with depressed LVSF associated with heart failure should have a minimal increase or a decrease in SA from upright to supine. ICG data were obtained in 12 patients without heart disease and with normal LVSF and 18 patients with clinically diagnosed heart failure. Consistent with the hypothesis, patients with normal LVSF had a significant increase in SA from upright to supine, whereas heart failure patients had a minimal increase or a decrease in SA from upright to supine. This ICG procedure may be useful for monitoring the trend of patient response to titration of beta blockers and other medications. ICG potentially could be used to detect worsening LVSF and provide a means of measurement for adjusting treatment.

Validation study of an automated electronic acute lung injury screening tool

OBJECTIVE The authors designed an automated electronic system that incorporates data from multiple hospital information systems to screen for acute lung injury (ALI) in mechanically ventilated patients. The authors evaluated the accuracy of this system in diagnosing ALI in a cohort of patients with major trauma, but excluding patients with congestive heart failure (CHF). DESIGN Single-center validation study. Arterial blood gas (ABG) data and chest radiograph (CXR) reports for a cohort of intensive care unit (ICU) patients with major trauma but excluding patients with CHF were screened prospectively for ALI requiring intubation by an automated electronic system. The system was compared to a reference standard established through consensus of two blinded physician reviewers who independently screened the same population for ALI using all available ABG data and CXR images. The system's performance was evaluated (1) by measuring the sensitivity and overall accuracy, and (2) by measuring concordance with respect to the date of ALI identification (vs. reference standard). MEASUREMENTS One hundred ninety-nine trauma patients admitted to our level 1 trauma center with an initial injury severity score (ISS) >/= 16 were evaluated for development of ALI in the first five days in an ICU after trauma. Main RESULTS The system demonstrated 87% sensitivity (95% confidence interval [CI] 82.3-91.7) and 89% specificity (95% CI 84.7-93.4). It identified ALI before or within the 24-hour period during which ALI was identified by the two reviewers in 87% of cases. CONCLUSIONS An automated electronic system that screens intubated ICU trauma patients, excluding patients with CHF, for ALI based on CXR reports and results of ABGs is sufficiently accurate to identify many early cases of ALI.

Implantable hemodynamic monitors

The evaluation and management of volume status in patients with heart failure is a challenge for most clinicians. In addition, such an evaluation is possible only during a personal clinician-patient interface. The ability to acquire hemodynamic data continuously with the help of implanted devices with remote monitoring capability can provide early warning of heart failure decompensation and thus may aid in preventing hospitalizations for heart failure. The data obtained also may improve the understanding of the disease process. It is important for the clinician treating patients who have heart failure to become acquainted with this type of technology and learn to interpret and use these data appropriately. This article reviews the implantable hemodynamics monitors currently available.

Acute decompensated heart failure: pathophysiology and treatment

Acute decompensated heart failure (ADHF) is an important milestone in the clinical course of heart failure (HF). It is an event associated with a significant deterioration in the prognosis of HF. Despite the progress that has been made in the development of new pharmacologic and nonpharmacologic therapy for HF, there is surprisingly limited advancement in the treatment of acute HF. There are currently no guidelines for the treatment of ADHF. This is a review of the current diagnostic evaluation and treatment of patients with ADHF.

Radiographic measures of intravascular volume status: the role of vascular pedicle width

PURPOSE OF REVIEW

A valid, low-cost, high-yield instrument to assess intravascular volume status in critically ill patients does not exist. The portable chest X-ray is a common part of any intensivist's or chest clinician's daily rounds.

RECENT FINDINGS

A simple, objective, valid measure of intravascular volume status, the vascular pedicle width, remains underappreciated in the medical literature. While more invasive, more expensive, and less common technologies are looked upon to assist in the clinical evaluation of volume status among critically ill patients, the vascular pedicle width stands alone in its low-cost, nearly risk-free potential to impact clinical practice. Even as the daily chest X-ray has become less common in practice, the role of measuring vascular pedicle width is potentially significant, particularly among mechanically ventilated patients. A standardized approach to reading the portable chest X-ray (supine or erect) is needed to facilitate interpretation of complex medical problems among the critically ill. Prospective evaluation of its appropriate use, particularly as compared with other, typically more invasive measures of intravascular volume, is warranted.

SUMMARY

Vascular pedicle width measurement using a standardized approach to daily chest X-ray interpretation represents untapped potential for improving the non-invasive assessment of volume status in critically ill patients.

Implantable hemodynamic monitoring devices in heart failure

The syndrome of heart failure is characterized by symptoms that are relatively insensitive and nonspecific. Physical diagnosis may be unreliable even in the hands of experienced clinicians despite the presence of significantly elevated filling pressures or a significantly depressed cardiac output. Over the past decade, the implantable hemodynamic monitor (IHM) has been developed as means of measuring intracardiac pressures over time and understanding the nuances of the hemodynamic derangements of this condition. With improved ability to accurately assess and monitor filling pressures, clinicians can more precisely adjust therapy with the goal of improving patient symptoms and possibly outcomes. Future directions include using the IHM to assist in management of other cardiovascular diseases, such as pulmonary arterial hypertension, and combining this technology with other implanted devices, such as defibrillators.

Predictors of Elevated B-Type Natriuretic Peptide Concentrations in Dyspneic Patients Without Heart Failure: An Analysis From the Breathing Not Properly Multinational Study

STUDY OBJECTIVE

B-type natriuretic peptide (BNP) is an established tool for the diagnosis of acute congestive heart failure in patients presenting with dyspnea. Some patients have moderately elevated BNP levels (ie, 100 to 500 pg/mL) in the absence of acute congestive heart failure. The objective of the current study was to identify independent predictors of elevated BNP concentrations in the absence of congestive heart failure.

METHODS

We studied 781 patients without acute congestive heart failure and BNP levels 0 to 500 pg/mL drawn from a cohort of 1,586 patients with acute dyspnea who had BNP levels measured on emergency department arrival. Two cardiologists blinded to BNP results reviewed all clinical data and categorized patients according to whether they had acute congestive heart failure or not.

RESULTS

Independent predictors of elevated BNP levels (ie, >100 pg/mL) were a medical history of atrial fibrillation, radiographic cardiomegaly, decreased blood hemoglobin concentration, decreased body mass index, and increased age.

CONCLUSION

Knowledge of these commonly obtained variables should aid clinicians in the interpretation of moderately elevated BNP results in patients presenting with acute dyspnea in the emergency department.

Congestive Heart Failure: A Review and Case Report From a Chiropractic Teaching Clinic

OBJECTIVE

To discuss the case of a 62-year-old woman with congestive heart failure (CHF), precipitated by a previous arteriovenous malformation, and to review the clinical presentation, pathophysiology, and treatment options for patients with CHF.

CLINICAL FEATURES

The patient complained of pain, rapid weight gain, and shortness of breath. The index event for this patient was known to be an arteriovenous malformation. Biventricular cardiomegaly with pulmonary venous hypertension was evident on chest radiographs.

INTERVENTION AND OUTCOME

The patient received both medical care (drug therapy) and chiropractic care (manipulation and soft tissue techniques to alleviate symptoms and discomfort).

CONCLUSION

Patients with known and undiagnosed CHF may visit the chiropractic physician; thus, knowledge of comprehensive care, differential diagnosis, and continuity of care are important. Chiropractic management may be helpful in alleviating patient discomfort. Further clinical investigations may help to clarify the role of complementary and alternative care in the diagnosis and treatment of CHF.

A systematic review finds that diagnostic reviews fail to incorporate quality despite available tools

BACKGROUND AND OBJECTIVE

To review existing quality assessment tools for diagnostic accuracy studies and to examine to what extent quality was assessed and incorporated in diagnostic systematic reviews.

METHODS

Electronic databases were searched for tools to assess the quality of studies of diagnostic accuracy or guides for conducting, reporting or interpreting such studies. The Database of Abstracts of Reviews of Effects (DARE; 1995-2001) was used to identify systematic reviews of diagnostic studies to examine the practice of quality assessment of primary studies.

RESULTS

Ninety-one quality assessment tools were identified. Only two provided details of tool development, and only a small proportion provided any indication of the aspects of quality they aimed to assess. None of the tools had been systematically evaluated. We identified 114 systematic reviews, of which 58 (51%) had performed an explicit quality assessment and were further examined. The majority of reviews used more than one method of incorporating quality.

CONCLUSION

Most tools to assess the quality of diagnostic accuracy studies do not start from a well-defined definition of quality. None has been systematically evaluated. The majority of existing systematic reviews fail to take differences in quality into account. Reviewers should consider quality as a possible source of heterogeneity.

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

PURPOSE

To compare chest radiographic findings and circulating B-type natriuretic peptide (BNP) levels as an adjunct to clinical findings in the diagnosis of heart failure in patients presenting with acute dyspnea.

METHODS

The diagnostic performance of radiographic evidence of cardiomegaly/redistribution and BNP levels > or =100 pg/mL as indicators of heart failure were assessed in 880 patients presenting with acute dyspnea to the emergency departments of five U.S. and two European teaching hospitals. BNP levels were determined by a rapid, point-of-care device. Two blinded cardiologists reviewed all clinical data and categorized patients as to whether they had acute heart failure (n = 447) or not (n = 433).

RESULTS

Three-factor analyses showed that BNP levels > or =100 pg/mL contributed significantly to the prediction of heart failure over each of the radiographic indicators. In a multivariate logistic regression analysis, both BNP levels > or =100 pg/mL (odds ratio [OR] = 12.3; 95% confidence interval [CI]: 7.4 to 20.4) and radiographic findings of cardiomegaly (OR = 2.3; 95% CI: 1.4 to 3.7), cephalization (OR = 6.4; 95% CI: 3.3 to 12.5), and interstitial edema (OR = 7.0; 95% CI: 2.9 to 17.0) added significant, predictive information above historical and clinical predictors of heart failure.

CONCLUSION

In patients presenting to the emergency department with acute dyspnea, BNP levels and chest radiographs provide complementary diagnostic information that may be useful in the early evaluation of heart failure.

Epidemiology and clinical aspects of congestive heart failure

Congestive heart failure (CHF) is an increasing problem for healthcare systems in all developed countries. The prevalence is increasing partly due to ageing of the population, but also due to improved survival from acute cardiac disease such as myocardial infarction. Advances in diagnostic techniques and better understanding of the pathophysiology offer many opportunities for substantial improvement in the management of CHF. This article reviews the current epidemiology of CHF and the related diagnostic issues.

Management of Acute Decompensated Heart Failure in the Emergency Department

Heart failure, a disease of epidemic proportions, has a tremendous clinical and financial impact on the US health care system. With more than 5 million Americans diagnosed with heart failure and 5-year mortality approaching 50%, it is the most common cause of hospitalization in patients older than 65 years and is the single most expensive diagnosis in the US health care system. Because the average US hospital loses more than 1000 dollars per heart failure admission, effective therapies that decrease length of stay, reduce hospital costs, and prevent 30-day readmissions are needed. This article reviews the relevant pathophysiology of heart failure, discusses the newest diagnostic strategies for emergency department diagnoses, evaluates recent advances and effects of early aggressive therapies, and presents a suggested algorithm for the treatment of acutely decompensated heart failure in emergency departments.

Heart failure in primary care: qualitative study of current management and perceived obstacles to evidence-based diagnosis and management by general practitioners

BACKGROUND

Chronic heart failure is a common clinical condition with high morbidity and mortality. Despite the evidence that appropriate treatment with angiotensin-converting enzyme inhibitors can improve morbidity, primary care studies show that patients with heart failure are incorrectly diagnosed and inadequately treated.

AIM

To explore general practitioners' accounts of their management of patients with heart failure and identify the perceived obstacles to diagnosis and management.

METHODS

We conducted this qualitative study using semi-structured interviews in 18 general practices. The practices were stratified on the basis of size, location, and the level of practice development. The interviews were based on a schedule of open questions based on the literature on diagnosis and management of patients with heart failure. Transcriptions of the audiotaped interviews were independently analysed by two researchers and analysis was based on open coding using a constant comparative approach. Categories were reduced to major themes.

RESULTS

General practitioners suspect heart failure when patients present with breathlessness or ankle oedema. Many general practitioners reported that they would diagnose heart failure after respiratory examination and a positive finding of basal crepitations. Many general practitioners arrange a chest X-ray to establish the diagnosis and some arrange an electrocardiogram. A few general practitioners mentioned that they diagnosed heart failure with a trial of diuretics. Obstacles to diagnosis were mentioned by most general practitioners and included lack of facilities for appropriate investigations (especially echocardiography) and lack of time and expertise. Obstacles to management included lack of time, high cost of drugs, difficulty with diagnosis, selection bias towards younger patients and not having the confidence to initiate angiotensin-converting enzyme inhibitors. Many general practitioners were unaware of the impact angiotensin-converting enzyme inhibitors can have on morbidity and mortality.

CONCLUSIONS

Although symptoms of heart failure are not sufficiently specific for diagnosing patients with heart failure, many general practitioners in European countries treat people with suspected heart failure on the basis of symptoms and signs alone. This study has identified many obstacles to the diagnosis and management of heart failure that may explain why patients are inadequately managed in primary care. Specific implementation strategies need to be tailored to overcome these obstacles.

Using the chest radiograph to determine intravascular volume status: the role of vascular pedicle width

Due to concerns about the efficacy and safety of using pulmonary artery catheterization to evaluate hemodynamic status, noninvasive diagnostic testing has gained increased importance. This article focuses on both the supportive evidence and the limitations of applying the vascular pedicle width (VPW), which is the mediastinal silhouette of the great vessels, as an aid in the assessment of patients' intravascular volume status. The objective measurement of the VPW obtained from either upright or supine chest radiographs (CXRs which are often already available though not fully utilized) can increase the accuracy of the clinical and radiographic assessment of intravascular volume status by 15 to 30%, and this value may be even higher when VPW is used serially within the same patient. Regardless of the presence or absence of pulmonary edema, the best VPW cutoff for differentiating a high vs normal to low intravascular volume status is 70 mm. Patients with a VPW of > 70 mm coupled with a cardiothoracic ratio of > 0.55 are more than three times more likely to have a pulmonary artery occlusion pressure > 18 mm Hg than are patients without these radiographic findings. We suggest a management algorithm for utilizing the VPW, and whether or not such an approach will offer superior patient outcomes requires prospective investigation. Reappraisal of the VPW and other roentgenographic signs should be incorporated into newly implemented studies of the Swan-Ganz catheter, ICU echocardiography, portable CT scans, and other costlier technologies. While such investigations may refine the optimum application of the portable CXR, conventional and digital supine radiographs should retain an important role in the diagnosis and management of critically ill patients. Lastly, the measurement of the VPW should be incorporated into the training of chest clinicians and radiologists.

Radiologic determination of intravascular volume status using portable, digital chest radiography: a prospective investigation in 100 patients

OBJECTIVE

To answer the following questions: Can the digital chest roentgenogram (CXR) be used to differentiate patients' volume status? Do clinical data alter radiologists' accuracy in interpreting the digital CXR?

DESIGN

Prospective cohort study.

SETTING

Nine adult intensive care units of a tertiary care medical center.

PATIENTS

One hundred thirty-five consecutive patients with pulmonary artery catheters, of whom 35 were excluded because of unacceptable pulmonary artery occlusion pressure (PAOP) tracings.

METHODS

Each patient had a portable, anteroposterior, supine digital CXR. Clinicians evaluated volume status and then measured hemodynamic data within 1 hr of the CXR. Digital CXRs were independently interpreted on two separate occasions (with and without clinical information) by three experienced chest radiologists, and these interpretations were compared with hemodynamic data.

RESULTS

Of the 100 patients, 39 had PAOP >18 mm Hg, whereas 61 had PAOP <18 mm Hg. Radiologists' accuracy in differentiating volume status increased with incorporation of clinical data (56% without vs. 65% with clinical data, p =.009). Using objective receiver operating characteristic-derived cutoffs of 70 mm for vascular pedicle width and 0.55 for cardiothoracic ratio, radiologists' accuracy in differentiating PAOP >18 mm Hg from PAOP <18 mm Hg was 70%. The intrareader and the inter-reader correlation coefficients were very high. The likelihood ratio of the CXR in determining volume status using the objective vascular pedicle width and cardiothoracic ratio measures was 3.1 (95% confidence interval, 1.9-6.0), significantly higher than subjective CXR interpretations with and without clinical data (p <.001).

CONCLUSIONS

Differentiating intravascular volume status with portable, supine, digital CXRs may be improved by using objective cutoffs of vascular pedicle width >70 mm and cardiothoracic ratio >0.55 or by incorporating clinical data.

A Rapid Access Heart Failure Clinic provides a prompt diagnosis and appropriate management of new heart failure presenting in the community

BACKGROUND AND AIMS

The diagnosis of heart failure is an important clinical problem and yet reported diagnostic accuracy in primary care is less than 50%. We established a Rapid Access Heart Failure Clinic (RAHFC) in a district general hospital serving a population of 292,000 in SE London, UK, to diagnose and manage new cases of heart failure presenting for the first time in the community.

METHODS

Patients with suspected new onset heart failure were referred by their Primary Care Physician without appointment for clinical assessment on the same or next working day. Assessment by a specialist registrar in cardiology included history, examination, chest X-ray, electrocardiogram (ECG) and echocardiogram. When a diagnosis of heart failure was made appropriate treatment, including angiotensin converting enzyme inhibitors (ACEI), was started.

RESULTS

Over 15 months 383 patients were seen (0.4 cases/100,000 population/weekday) 178/383 (46%) were considered to have definite or possible heart failure at the initial assessment in the RAHFC. A normal ECG (negative predictive value 94%) and chest X-ray virtually excluded the diagnosis of heart failure. After subsequent specialist investigations and follow-up, including a trial of therapy where appropriate, 101/383 (26%) were finally diagnosed as clinical heart failure. ACEI therapy was commenced in 56/57 (98%) of patients in whom it was considered appropriate.

CONCLUSION

The RAHFC provided rapid assessment, prompt diagnosis and early introduction of life prolonging therapy for patients presenting with suspected heart failure in the community.

The use of clinical information in diagnosing chronic heart failure: a comparison between general practitioners, cardiologists, and students

In a clinical judgement analysis study, 27 general practitioners, 22 cardiologists, and 21 medical students assessed 40 case vignettes with regard to the probability of heart failure, in order to study the weights of different kinds of information (cues) measured by the regression coefficients in a multiple regression model. The vignettes were based on actual patients. We found that diagnostic accomplishment and diagnostic strategies were surprisingly similar on the group level, but very different on the individual level. The most important cues for the participants were cardiac enlargement and pulmonary stasis. Strategies in which cardiac enlargement was the predominating cue led to a higher diagnostic accomplishment; a third of the participants used such strategies. The cues given in the vignettes could have been utilized more efficiently; cardiac enlargement seems to be more important and "classical" symptoms less important for predicting heart failure than the participants realize.

Diuretic therapy in elderly heart failure patients with and without left ventricular systolic dysfunction

Long term prescription of diuretics for heart failure is very prevalent among elderly patients, although the rationale for such a treatment strategy is often unclear, as diuretics are not indicated if volume overload is absent. The concept of diastolic heart failure in the elderly might particularly change the role of diuretic therapy, since diuretics may have additional adverse effects in these patients. This paper reviews the effects of diuretic therapy in elderly patients with heart failure, emphasising the differences between patients with normal and decreased left ventricular systolic function. Studies on diuretic withdrawal in elderly patients with heart failure are discussed, with emphasis on issues involved in decision making such as diuretic dose reduction and withdrawal in elderly patients and factors that have been established to predict successful withdrawal. Existing guidelines on the prescription of diuretics in elderly patients with heart failure with normal and decreased left ventricular systolic function and in those with diastolic heart failure are also discussed. By reducing intravascular volume, diuretics may further impair ventricular diastolic filling in patients with diastolic heart failure and thus reduce stroke volume. Indeed, preliminary studies demonstrate that diuretics may provoke or aggravate hypotension on standing and after meals in these patients. Therefore, it is suggested that elderly patients with heart failure with intact left ventricular systolic function should not receive long term diuretic therapy, unless proven necessary to treat or prevent congestive heart failure. This implies that physicians should carefully evaluate the opportunities for diuretic dose tapering or withdrawal in all of these patients, and that a cautiously guided intermittent diuretic treatment modality may be critical in the care for older patients with heart failure with intact left ventricular systolic function.

Differences among geriatricians, general internists, and cardiologists in the care of patients with heart failure: a cautionary tale of quality assessment

OBJECTIVES

To describe differences in the characteristics, processes of care, and resource utilization of patients with heart failure cared for by geriatricians, general internists, cardiologists, and combinations of physicians.

DESIGN

A retrospective cohort study.

SETTING

An urban academic medical center.

PARTICIPANTS

A total of 439 outpatients with a billing diagnosis of heart failure or cardiomyopathy who were treated by geriatricians, general internists, cardiologists, and combinations of physicians.

MEASUREMENTS

Demographic and clinical characteristics, medication use, diagnostic testing, hospitalizations, and inpatient and outpatient costs were measured.

RESULTS

Compared with patients of cardiologists, patients cared for by geriatricians were older, more likely to have hypertension, diastolic dysfunction, and high comorbidity, and less likely to undergo echocardiography, cardiac catheterization, and electrocardiography. Use of angiotensin-converting enzyme inhibitors was similar among patients with reduced systolic function. Patients cared for by geriatricians had the same costs, rates of hospitalization, and likelihood of being symptomatic as patients of cardiologists.

CONCLUSIONS

The processes of care for patients with heart failure seen solely by geriatricians differ from those for patients seen by other physicians, but the case-mix also varies. Assessment of left ventricular function by geriatricians probably needs to be increased. However, although they were older and had more comorbidity, patients of geriatricians had total costs and symptomatology similar to those of patients of cardiologists. Future work is needed to identify those patients most likely to benefit from treatment by geriatricians and to determine how care can be optimally coordinated among different types of physicians and health providers.

Appraising pulmonary edema using supine chest roentgenograms in ventilated patients

The role of portable, anteroposterior, supine chest X-rays (CXRs) in distinguishing hydrostatic pulmonary edema (HPE) from permeability pulmonary edema (PPE) in mechanically ventilated patients is controversial. We prospectively obtained and evaluated such CXRs in 33 supine, mechanically ventilated intensive-care-unit patients with pulmonary artery catheters. Three chest radiologists independently reviewed CXRs without clinical information and recorded the cardiothoracic (CT) ratio, vascular pedicle width (VPW), and other radiographic features commonly used to evaluate pulmonary edema. Hydrostatic pulmonary edema was associated with a larger CT ratio (p < 0.001), subjective impressions of cardiomegaly (p < 0.01), and increased VPW (p = 0.02). There was a significant correlation between the pulmonary artery occlusion pressure and the VPW (r = 0.45, p = 0.0076) and CT ratio (r = 0.52, p = 0.0016), as well as between the VPW and CT ratio (r = 0.49, p = 0.0032). Despite this detailed evaluation of the CXRs, the mean accuracy of the radiologists' clinical diagnosis of HPE versus PPE was 41%, and 15 of 19 (79%) of PPE patients showed one or more roentgenographic signs of volume overload. Receiver-operating-characteristic curves were constructed to determine optimum cut-off values of VPW and CT ratio associated with HPE. Hydrostatic pulmonary edema was found to correlate best using a VPW > 63 mm coupled to a CT ratio > 0.52 (p = 0.027). With this combination of objective criteria, radiologists' diagnostic accuracy could have been increased to 73%. We therefore conclude that measurements of CT ratio and VPW correlate with pulmonary artery occlusion pressure in supine, mechanically ventilated patients. Distinction of hydrostatic from permeability pulmonary edema is difficult using portable, supine CXRs, but readily assessed radiologic signs may contribute to the correct diagnosis.