Comparison of Hand-Carried Ultrasound Assessment of the Inferior Vena Cava and N-Terminal Pro-Brain Natriuretic Peptide for Predicting Readmission After Hospitalization for Acute Decompensated Heart Failure

Comparison of expert and novice sonographers' performance in focused lung ultrasonography in dyspnea (FLUID) to diagnose patients with acute heart failure syndrome

OBJECTIVES

The goal of this study was to examine the ability of emergency physicians who are not experts in emergency ultrasound (US) to perform lung ultrasonography and to identify B-lines. The hypothesis was that novice sonographers are able to perform lung US and identify B-lines after a brief intervention. In addition, the authors examined the diagnostic accuracy of B-lines in undifferentiated dyspneic patients for the diagnosis of acute heart failure syndrome (AHFS), using an eight-lung-zone technique as well as an abbreviated two-lung-zone technique.

METHODS

This was a prospective, cross-sectional study of patients who presented to the emergency department (ED) with acute dyspnea from May 2009 to June 2010. Emergency medicine (EM) resident physicians, who received a 30-minute training course in thoracic US examinations, performed lung ultrasonography on patients presenting to the ED with undifferentiated dyspnea. They attempted to identify the presence or absence of sonographic B-lines in eight lung fields based on their bedside US examinations. An emergency US expert blinded to the diagnosis and patient presentation, as well as to the residents' interpretations of presence of B-lines, served as the criterion standard. A secondary outcome determined the accuracy of B-lines, using both an eight-lung-zone and a two-lung-zone technique, for predicting pulmonary edema from AHFS in patients presenting with undifferentiated dyspnea. Two expert reviewers who were blinded to the US results determined the clinical diagnosis of AHFS.

RESULTS

A cohort of 66 EM resident physicians performed lung US on 380 patients with a range of 1 to 28 examinations, a mean of 5.8 examinations, and a median of three examinations performed per resident. Compared to expert interpretation, lung US to detect B-lines by inexperienced sonographers achieved the following test characteristics: sensitivity 85%, specificity 84%, positive likelihood ratio (+LR) 5.2, negative likelihood ratio (-LR) 0.2, positive predictive value (PPV) 64%, and negative predictive value (NPV) 94%. Regarding the secondary outcome, the final diagnosis was AHFS in 35% of patients (134 of 380). For novice sonographers, one positive lung zone (i.e., anything positive) had a sensitivity of 87%, a specificity of 49%, a +LR of 1.7, a -LR of 0.3, a PPV of 50%, and an NPV of 88% for predicting AHFS. When all eight lung zones were determined positive (i.e., totally positive) by novice sonographers, the sensitivity was 19%, specificity was 97%, +LR was 5.7, -LR was 0.8, PPV was 76%, and NPV was 68% for predicting AHFS. The areas under the curve for novice and expert sonographers were 0.77 (95% CI = 0.72 to 0.82) and 0.76 (95% CI = 0.71 to 0.82), respectively.

CONCLUSIONS

Novice sonographers can identify sonographic B-lines with similar accuracy compared to an expert sonographer. Lung US has fair predictive value for pulmonary edema from acute heart failure in the hands of both novice and expert sonographers.

Pocket-sized focused cardiac ultrasound: strengths and limitations

Focused cardiac ultrasound (FCU) has emerged in recent years and has created new possibilities in the clinical assessment of patients both in and out of hospital. The increasing portability of echocardiographic devices, with some now only the size of a smartphone, has widened the spectrum of potential indications and users, from the senior cardiologist to the medical student. However, many issues still need to be addressed, especially the acknowledgment of the advantages and limitations of using such devices for FCU, and the extent of training required in this rapidly evolving field. In recent years, an increasing number of studies involving FCU have been published with variable results. This review outlines the evidence for the use of FCU with pocket-echo to address specific questions in daily clinical practice.

Diagnostic point-of-care ultrasound for hospitalists

We review the literature on diagnostic point-of-care ultrasound applications most relevant to hospital medicine and highlight gaps in the evidence base. Diagnostic point-of-care applications most relevant to hospitalists include cardiac ultrasound for left ventricular systolic function, pericardial effusion, and severe mitral regurgitation; lung ultrasound for pneumonia, pleural effusion, pneumothorax, and pulmonary edema; abdominal ultrasound for ascites, aortic aneurysm, and hydronephrosis; and venous ultrasound for central venous volume assessment and lower extremity deep venous thrombosis. Hospitalists and other frontline providers, as well as physician trainees at various levels of training, have moderate to excellent diagnostic accuracy after brief training programs for most of these applications. Despite the evidence supporting the diagnostic accuracy of point-of-care ultrasound, experimental evidence supporting its clinical use by hospitalists is limited to cardiac ultrasound.

Feasibility and reliability of pocket-size ultrasound examinations of the pleural cavities and vena cava inferior performed by nurses in an outpatient heart failure clinic

BACKGROUND

Routine assessment of volume state by ultrasound may improve follow-up of heart failure patients.

AIMS

We aimed to study the feasibility and reliability of focused pocket-size ultrasound examinations of the pleural cavities and the inferior vena cava performed by nurses to assess volume state at an outpatient heart failure clinic.

METHODS

Ultrasound examinations were performed in 62 included heart failure patients by specialized nurses with a pocket-size imaging device (PSID). Patients were then re-examined by a cardiologist with a high-end scanner for reference within 1 h. Specialized nurses were able to obtain and interpret images from both pleural cavities and the inferior vena cava and estimate the volume status in all patients.

RESULTS

Time consumption for focused ultrasound examination was median 5 min. In total 26 patients had any kind of pleural effusion (in 39 pleural cavities) by reference. The sensitivity, specificity, positive and negative predictive values were high, all ≥ 92%. The correlations with reference were high for all measurements, all r ≥ 0.79. Coefficients of variation for end-expiratory dimension of inferior vena cava and quantification of pleural effusion were 10.8% and 12.7%, respectively.

CONCLUSIONS

Specialized nurses were, after a dedicated training protocol, able to obtain reliable recordings of both pleural cavities and the inferior vena cava by PSID and interpret the images in a reliable way. Implementing focused ultrasound examinations to assess volume status by nurses in an outpatient heart failure clinic may improve diagnostics, and thus improve therapy.

Inferior vena cava parameters predict re-admission in ischaemic heart failure

BACKGROUND

The clinical history of heart failure (HF) is usually characterized by frequent hospitalizations for decompensation. Therefore, several markers of subclinical hemodynamic congestion are under investigation for predicting early rehospitalization. In this field, the potential of ultrasound inferior vena cava (IVC) assessment has been recently investigated in HF but not yet assessed in the different aetiological categories.

MATERIAL AND METHODS

Forty-eight patients admitted for decompensated HF (n = 25 with ischaemic heart disease [IHD] and n = 23 non-IHD) underwent biochemical examination (including NT-proBNP), echocardiography and IVC assessment by hand-carried ultrasound (HCU). During 60-day follow-up after discharge, the re-hospitalization rate for HF was recorded to investigate the predictive power of NT-proBNP and IVC assessment among the two study groups.

RESULTS

IHD and non-IHD patients with HF were similar except for gender distribution. During follow-up, 16·7% of patients were rehospitalized for decompensated HF, with higher prevalence in IHD group (28% vs. 4·3% P = 0·031). IVC assessment at discharge significantly predicted re-admission in the overall population and in IHD group, whereas NT-proBNP failed to predict rehospitalization in IHD group. In adjusted hazard ratio, only IVC min and the changes of IVC from admission significantly predicted re-admission. ROC analysis confirmed the change in IVC min as the best predictor of rehospitalization in patients with IHD.

CONCLUSION

This pilot study showed a higher early re-admission rate in patients with HF due to IHD. In addition, the change in IVC min diameter from admission to discharge was the best predictor of re-admission in patients with IHD.

Prognostic value of plasma ghrelin in predicting the outcome of patients with chronic heart failure

BACKGROUND AND AIMS

Ghrelin is an endogenous ligand of the growth hormone (GH) secretagogue receptor and is closely associated with chronic heart failure (CHF). We undertook this study to investigate the relevance of ghrelin in CHF prognosis.

METHODS

A total of 145 in-patients with CHF in NYHA class II, III or IV despite optimized therapy were prospectively included in the study, grouped according to NYHA class and compared with 55 healthy control subjects. Ghrelin and N-terminal pro-B-type natriuretic peptide (Nt pro-BNP) were measured in plasma by ELISA. Echocardiographic information was also measured, including left atrial dimension, left ventricular end-diastolic diameter, LV volume and left ventricular ejection fraction (LVEF). Patients were followed for 2 years or until major adverse cardiac events.

RESULTS

Plasma ghrelin levels were significantly lower in patients with CHF than in control subjects (p = 0.014). In addition, plasma ghrelin levels differed significantly with the severity of CHF. Notably, survival analysis showed that high ghrelin levels were an indicator of a favorable prognosis for CHF. Our results also showed that ghrelin correlated inversely with plasma Nt pro-BNP levels (r = -0.562, p <0.001) and positively with LVEF (r = 0.620, p <0.001) in patients with CHF. Furthermore, multivariate analysis showed that ghrelin levels were independently associated with adverse cardiac events (hazard ratio: 0.72; 95% CI: 0.64-0.81, p = 0.03).

CONCLUSIONS

Ghrelin is a new biomarker of CHF severity as well as a new prognostic predictor for patients with CHF. Future experimental and clinical studies are warranted to evaluate ghrelin as a novel prognostic tool and for its therapeutic potential in patients with CHF.

Prediction of 30-day heart failure-specific readmission risk by echocardiographic parameters

It is unknown whether echocardiographic morphologic and hemodynamic parameters have incremental value in predicting 30-day heart failure (HF)-specific readmission risk among patients admitted with HF. We performed a prospective cohort study of adult patients entering a transitional care program after HF hospitalization to assess the role of echocardiographic parameters in predicting 30-day HF-specific readmission risk. Patients were followed for at least 30 days postdischarge, and readmission outcomes were ascertained prospectively. A previously validated 30-day HF readmission score (Yale Center for Outcome Research and Evaluation [CORE]) was calculated using 20 clinical and pathology parameters. Atrial and ventricular morphologic and hemodynamic variables were obtained from the index hospitalization echocardiogram. A Cox proportional hazards model was used to identify variables associated with 30-day HF specific readmission risk. Among 283 patients (mean age 72 ± 14 years, 57% men, 54% ischemic HF, ejection fraction 35% ± 17%) who underwent echocardiography during index admission there were 46 HF specific readmissions. After risk adjustment, elevated echocardiographic right atrial pressure (RAP; hazard ratio [HR] 3.70, 95% confidence interval [CI] 1.82 to 7.52, p <0.001), left ventricular filling pressures (HR 7.46, 95% CI 2.31 to 24.14, p = 0.001), and weight change during admission (HR 0.93, 95% CI 0.87 to 0.99, p = 0.02) were independently associated with 30-day HF-specific readmission risk. However, only elevated RAP and left ventricular filling pressure added incremental prognostic value to the Yale-CORE HF readmission score. An E/e' threshold of 23 identified a subgroup at highest risk of readmission and provided a net 29% reclassification improvement over the Yale-CORE HF readmission score (p = 0.005).

Hospitalists' ability to use hand-carried ultrasound for central venous pressure estimation after a brief training intervention: a pilot study

BACKGROUND

Access to hand-carried ultrasound technology for noncardiologists has increased significantly, yet development and evaluation of training programs are limited.

OBJECTIVE

We studied a focused program to teach hospitalists image acquisition of inferior vena cava (IVC) diameter and IVC collapsibility index with interpretation of estimated central venous pressure (CVP).

METHODS

Ten hospitalists completed an online educational module prior to attending a 1-day in-person training session that included directly supervised IVC imaging on volunteer subjects. In addition to making quantitative assessments, hospitalists were also asked to visually assess whether the IVC collapsed more than 50% during rapid inspiration or a sniff maneuver. Skills in image acquisition and interpretation were assessed immediately after training on volunteer patients and prerecorded images, and again on volunteer patients at least 6 weeks later.

RESULTS

Eight of 10 hospitalists acquired adequate IVC images and interpreted them correctly on 5 of the 5 volunteer subjects and interpreted all 10 prerecorded images correctly at the end of the 1-day training session. At 7.4 ± 0.7 weeks (range, 6.9-8.6 weeks) follow-up, 9 of 10 hospitalists accurately acquired and interpreted all IVC images in 5 of 5 volunteers. Hospitalists were also able to accurately determine whether the IVC collapsibility index was more than 50% by visual assessment in 180 of 198 attempts (91% of the time).

CONCLUSIONS

After a brief training program, hospitalists acquired adequate skills to perform and interpret hand-carried ultrasound IVC images and retained these skills in the near term. Though calculation of the IVC collapsibility index is more accurate, coupling a qualitative assessment with the IVC maximum diameter measurement may be acceptable in aiding bedside estimation of CVP.

Measuring comorbidity in cardiovascular research: a systematic review

Background. Everything known about the roles, relationships, and repercussions of comorbidity in cardiovascular disease is shaped by how comorbidity is currently measured. Objectives. To critically examine how comorbidity is measured in randomized controlled trials or clinical trials and prospective observational studies in acute myocardial infarction (AMI), heart failure (HF), or stroke. Design. Systematic review of studies of hospitalized adults from MEDLINE CINAHL, PsychINFO, and ISI Web of Science Social Science databases. At least two reviewers screened and extracted all data. Results. From 1432 reviewed abstracts, 26 studies were included (AMI n = 8, HF n = 11, stroke n = 7). Five studies used an instrument to measure comorbidity while the remaining used the presence or absence of an unsubstantiated list of individual diseases. Comorbidity data were obtained from 1-4 different sources with 35% of studies not reporting the source. A year-by-year analysis showed no changes in measurement. Conclusions. The measurement of comorbidity remains limited to a list of conditions without stated rationale or standards increasing the likelihood that the true impact is underestimated.

The dilemma, causes and approaches to avoid recurrent hospital readmissions for patients with chronic heart failure

Heart failure is a progressive illness that carries significant morbidity and mortality. This highly prevalent illness leads to frequent, costly hospitalizations with approximately 50% of patients being readmitted within 6 months of initial hospitalization. While rehospitalization has been extensively studied in the past, little progress has been made in terms of reducing readmission rates of heart failure patients in the last decade despite increasing costs with impending resource limitations. We discuss disease-centered, physician-centered, and patient-centered factors that lead to rehospitalization as well as community/resource availability factors that contribute to rehospitalization of patients suffering from chronic heart failure. In addition, predictors of hospitalization and interventions that reduce hospitalization will be critically evaluated. With a complete understanding of heart failure rehospitalization, we hope the future holds more effective ways to prevent heart failure progression and thus rehospitalization, improved risk-stratification models to identify patients high-risk for rehospitalization, and sustained interventions that are customized according to the etiology of the clinical decline of heart failure patients that ultimately results in frequent rehospitalizations.

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.

Observations during development of an internal medicine residency training program in cardiovascular limited ultrasound examination

BACKGROUND

Despite the future potential of using ultrasound stethoscopes to augment the bedside cardiac physical, few data exist on a general cardiovascular imaging protocol that can be taught to physicians on a perpetual basis as a curriculum in graduate medical education.

METHODS

During the past decade, we developed and integrated a cardiovascular limited ultrasound training program within the confines of an internal medicine residency. The evidence-based rationale for the exam, the teaching methods, and curriculum are delineated, and subsequent observations regarding program requirements, proficiency, and academic outcomes are explored. Analysis of variance and linear regression assessed for relationships between academic scores, chief resident selection, and gender to proficiency in ultrasound.

RESULTS

A brief, 5-minute cardiovascular limited ultrasound exam (CLUE) was taught using both didactic and bedside methods, and practiced primarily within the cardiology consult, outpatient clinic, and intensive care rotations. Program costs were minimized by employing readily available institutional resources. After a 2-year lead-in training phase, the subsequent 4 years of senior resident performance (n = 41 residents) showed an 81% pass rate in CLUE competency. Resident ultrasound performance did not relate to academic scores (r = 0.05, P = 0.75), chief resident selection, nor gender. Observations regarding resident pitfalls in CLUE practice and increased participation in extracurricular research are described.

CONCLUSIONS

We report our initial experience in developing and implementing a training program for bedside cardiovascular ultrasound examination that employed evidence-based techniques, set proficiency goals, and assessed resident performance. It may be feasible to teach future internist-hospitalists the technique of bedside ultrasound during residency.

Correlation of natriuretic peptides and inferior vena cava size in patients with congestive heart failure

BACKGROUND

The inferior vena cava (IVC) diameter and degree of inspiratory collapse are used as echocardiographic indices in the estimation of right atrial pressure. Brain-natriuretic peptides (BNPs) are established biomarkers of myocardial wall stress. There is no information available regarding the association between the IVC diameter and BNPs in patients with heart failure and various degrees of systolic performance. The purpose of this investigation is to quantify the degree to which natriuretic peptides (BNP and N-terminal pro-B natriuretic peptide [NT-ProBNP]) and echocardiographic-derived indices of right atrial pressure correlate in this patient population.

METHODS

We examined 77 patients (mean age 61 ± 17 years, 44% male) with decompensated heart failure who underwent transthoracic echocardiography and, within a timeframe of 24 hours, determination of BNP and NT-ProBNP levels in venous blood. BNP and NT-ProBNP were analyzed after log transformation. The degree of association was measured by the correlation coefficient using the Pearson's method.

RESULTS

The mean ejection fraction was 50% ± 20%, and 33% of the study cohort had a remote history of heart failure. The mean IVC diameter was 1.85 cm ± 0.5, the mean BNP was 274 pg/mL, the confidence interval (CI) was 95% (95% CI: 197-382), and the mean NT-ProBNP was 1994 pg/mL (95% CI: 1331-2989). There was a positive, albeit small, association between IVC diameter and BNP (r = 0.24, 95% CI: 0.01-0.44; P = 0.03) and NT-ProBNP (r = 0.27, 95% CI: 0.05-0.47; P = 0.01). Among patients with different degrees of IVC collapse in response to inspiration, values for BNP and NT-ProBNP did not differ substantially (P = 0.36 and 0.46 for BNP and NT-ProBNP, respectively).

CONCLUSION

Natriuretic peptides correlate weakly with IVC size and do not predict changes in response to intrathoracic pressure.

Predictors of re-hospitalization in patients with chronic heart failure

Heart failure (HF) is a chronic, progressive illness that is highly prevalent in the United States and worldwide. This morbid illness carries a very poor prognosis, and leads to frequent hospitalizations. Repeat hospitalization in HF is both largely burdensome to the patient and the healthcare system, as it is one of the most costly medical diagnoses among Medicare recipients. For years, investigators have strived to determine methods to reduce hospitalization rates of HF patients. Despite such efforts, recent reports indicate that re-hospitalization rates remain persistently high, without any improvement over the past several years and thus, this topic clearly needs aggressive attention. We performed a key-word search of the literature for relevant citations. Published articles, limited to English abstracts indexed primarily in the PubMed database through the year 2011, were reviewed. This article discusses various clinical parameters, serum biomarkers, hemodynamic parameters, and psychosocial factors that have been reviewed in the literature as predictors of re-hospitalization of HF patients. With this information, our hope is that the future holds better risk-stratification models that will allow providers to identify high-risk patients, and better customize effective interventions according to the needs of each individual HF patient.

Does a simple bedside sonographic measurement of the inferior vena cava correlate to central venous pressure?

BACKGROUND

Bedside ultrasound has been suggested as a non-invasive modality to estimate central venous pressure (CVP).

OBJECTIVE

Evaluate a simple bedside ultrasound technique to measure the diameter of the inferior vena cava (IVC) and correlate to simultaneously measured CVP. Secondary comparisons include anatomic location, probe orientation, and phase of respiration.

METHODS

An unblinded prospective observation study was performed in an emergency department and critical care unit. Subjects were a convenience sample of adult patients with a central line at the superior venocaval-atrial junction. Ultrasound measured transverse and longitudinal diameters of the IVC at the subxiphoid, suprailiac, and mid-abdomen, each measured at end-inspiration and end-expiration. Correlation and regression analysis were used to relate CVP and IVC diameters.

RESULTS

There were 72 subjects with a mean age of 67 years (range 21-94 years), 37 (53%) male, enrolled over 9 months. Seven subjects were excluded for tricuspid valvulopathy. Primary diagnoses were: respiratory failure 12 (18%), sepsis 11 (17%), and pancreatitis 3 (5%). There were 28 (43%) patients mechanically ventilated. Adequate measurements were obtainable in 57 (89%) using the subxiphoid, in 44 (68%) using the mid-abdomen, and in 28 (43%) using the suprailiac views. The correlation coefficients were statistically significant at 0.49 (95% confidence interval [CI] 0.26-0.66), 0.51 (95% CI 0.23-0.71), and 0.50 (95% CI 0.14-0.74) for end-inspiratory longitudinal subxiphoid, midpoint, and suprailiac views, respectively. Transverse values were statistically significant at 0.42 (95% CI 0.18-0.61), 0.38 (95% CI 0.09-0.61), and 0.67 (95% CI 0.40-0.84), respectively. End-expiratory measurements gave similar or slightly less significant values.

CONCLUSION

The subxiphoid was the most reliably viewed of the three anatomic locations; however, the suprailiac view produced superior correlations to the CVP. Longitudinal views generally outperformed transverse views. A simple ultrasound measure of the IVC yields weak correlation to the CVP.

Cardiopulmonary limited ultrasound examination for "quick-look" bedside application

Although taking a "quick look" at the heart using a small ultrasound device is now feasible, a formal ultrasound imaging protocol to augment the bedside physical examination has not been developed. Therefore, we sought to evaluate the diagnostic accuracy and prognostic value of a cardiopulmonary limited ultrasound examination (CLUE) using 4 simplified diagnostic criteria that would screen for left ventricular dysfunction (LV), left atrial (LA) enlargement, inferior vena cava plethora (IVC+), and ultrasound lung comet-tail artifacts (ULC+) in patients referred for echocardiography. The CLUE was tested by interpretation of only the parasternal LV long-axis, subcostal IVC, and 2 lung apical views in each of 1,016 consecutive echocardiograms performed with apical lung imaging. For inpatients, univariate and multivariate logistic regression analyses were performed to assess the relations between mortality, CLUE findings, age, and gender. In this echocardiographic referral series, 78% (n = 792) were inpatient and 22% (n = 224) were outpatient. The CLUE criteria demonstrated a sensitivity, specificity, and accuracy for a LV ejection fraction of ≤40% of 69%, 91%, and 89% and for LA enlargement of 75%, 72%, and 73%, respectively. CLUE findings of LV dysfunction, LA enlargement, IVC+, and ULC+ were seen in 16%, 53%, 34%, and 28% of inpatients. The best multivariate logistic model contained 3 predictors of in-hospital mortality: ULC+, IVC+ and male gender, with adjusted odds ratios (95% confidence intervals) of 3.5 (1.4 to 8.8), 5.8 (2.1 to 16.4), and 2.3 (0.9 to 5.8), respectively. In conclusion, a CLUE consisting of 4 quick-look "signs" has reasonable diagnostic accuracy for bedside use and contains prognostic information.

Handcarried echocardiography to assess hemodynamics in acute decompensated heart failure

Heart failure is a major source of cardiovascular morbidity, including acute decompensations requiring hospitalization. Because most therapeutic interventions in acute heart failure target optimization of cardiac output and volume status, accurate assessment of these parameters at the point of care is critical to guide management. However, physician bedside assessments of left ventricular (LV) function and volume status have limited accuracy. Traditional echocardiographic platforms, while useful for assessing ventricular and valvular function and volume status, have limitations for bedside use or frequent serial evaluation. Handcarried cardiac ultrasound devices, with their substantially lower costs, portability, and ease of use, circumvent many of the limitations of traditional echocardiographic platforms. The diagnostic capabilities of handcarried devices provide the opportunity for ultrasound assessment of LV function and serial bedside evaluation of volume status in patients with acutely decompensated heart failure.

Hospitalist use of hand-carried ultrasound: preparing for battle

Hand-carried ultrasound (HCU) is a burgeoning technology at a critical point in its development as a general diagnostic technique. Despite the known safety and accuracy of ultrasound in radiology and echocardiography, the use of HCU to augment physical diagnosis by all physicians has yet unrealized potential. In order to incorporate ultrasound into a diagnostic model of routine bedside application, simple imaging and training protocols must first be derived and validated. Simplified cardiac ultrasound exams have already been validated to detect evidence-based targets such as subclinical atherosclerosis, heart failure, and elevated central venous pressures. However, for general examination of the acutely ill patient, it is the internist-hospitalist who should derive a full-body ultrasound examination, balancing training requirements with the numerous clinical applications potentially available. As the hospital's leading diagnostician with ultrasound expertise available in-house, the hospitalist could develop HCU so as to triage and refer more appropriately and limit unnecessary testing and hospital stays. Active involvement by hospitalists now in the planning of outcome, validation, and training studies, will be invaluable in the formation of an "ultrasound-assisted" physical examination in the future and will promote competent, cost-effective applications of HCU within general medical practice.

Use of hand carried ultrasound, B-type natriuretic peptide, and clinical assessment in identifying abnormal left ventricular filling pressures in patients referred for right heart catheterization

BACKGROUND

The estimation of left ventricular filling pressure (LVFP) remains a critical component in the management of patients with known or suspected acute heart failure syndromes. Although right heart catheterization (RHC) remains the gold standard, several noninvasive parameters, including clinical assessment, B-type natriuretic peptides (BNP), and echocardiography can approximate LVFP. We sought to use a combination of these measures to noninvasively predict high or low LVFP in a population referred for RHC.

METHODS AND RESULTS

The study consisted of validation of hand-carried ultrasound (HCU)-derived measurement of mitral E/E' against standard echocardiograms in 50 patients, as well as direct comparison of jugular venous pressure (JVP), a clinical congestion score, HCU-derived E/E' and maximum inferior vena cava diameter (IVCmax), and BNP with pulmonary capillary wedge pressure (PCWP) in another 50 patients. The mean age was 61 years, ejection fraction 40%, JVP 9 cm, BNP 948 pg/mL, IVCmax 2.1 cm, E/E' 13, and PCWP 21. All parameters performed well in determining PCWP >or=15 mm Hg, with clinical score performing the worst (area under the receiver-operator characteristic curve [AUC] 0.74), and IVCmax performing the best (AUC 0.89). JVP, in combination with HCU-derived parameters and BNP performed better than any of the individual tests alone (AUC 0.97 for combination of all 3).

CONCLUSIONS

Clinical score, JVP, HCU indices, and BNP perform well at identifying patients with a PCWP >or=15 mm Hg. Use of these indices alone or in combination can be used to identify and potentially monitor patients with high LVFP in the inpatient and outpatient settings.