Focused cardiac ultrasound as a predictor of readmission in acute decompensated heart failure

Integration of point-of-care ultrasound in a nurse practitioner-led heart failure clinic

BACKGROUND

Despite improved survival, one in five patients with heart failure (HF) is readmitted within 30 days of discharge. Assessing fluid status is challenging, with an estimated 50% accuracy when relying on physical examination alone. Pulmonary congestion is a risk factor for readmission and can manifest weeks before symptoms occur.

PURPOSE

To conduct a pilot study to assess for pleural effusion with point-of-care ultrasound (POCUS) and to evaluate inferior vena cava (IVC) noncollapsibility as a marker of volume status.

METHODS

A convenience sample of adults with HF (n = 21) were seen in a nurse practitioner (NP)-led postdischarge clinic within 12 days of hospitalization. The setting was a large tertiary care hospital. Inclusion criteria were patients with an HF diagnosis and Medicare insurance. The NP measured IVC diameter, assessed for collapsibility, and examined pleural cavities using a VSCAN POCUS device. Data were analyzed descriptively.

RESULTS

Pleural effusions were identified in three (14.3%) patients with POCUS and referred for thoracentesis. Inferior vena cava was noncollapsible in 5 (23.8%) patients; each of these patients required intervention for volume overload.

CONCLUSIONS

Point-of-care ultrasound can be used by NPs to identify patients with pleural effusions who may benefit from thoracentesis. Inferior vena cava noncollapsibility may be a predictor for volume overload.

IMPLICATIONS

Point-of-care ultrasound equips NPs with an extra tool to effectively manage HF.

Methods for the Assessment of Volume Overload and Congestion in Heart Failure

Acute decompensated heart failure entails a dysregulation of renal and cardiac function, with fluid volume excess or congestion being a key component. We provide an overview of methods for its assessment in clinical practice. Evaluation of congestion can be achieved using different methods including plasma biomarkers, measurement of blood volume from the volume of distribution of [131I]-human serum albumin, sonographic modalities, implantable devices, invasive measurements of volume status including right heart catheterization, and impedance methods. Integration into clinical practice of accessible, cost-effective, and evidence-based modalities for volume assessment will be pivotal in the management of acute decompensated heart failure.

A nomogram for predicting echocardiogram prescription in outpatients: an analysis of the NAMCS database

Background and objective

Cardiovascular disease is the leading cause of morbidity and mortality globally. Echocardiography is a commonly used method for assessing the condition of patients with cardiovascular disease. However, little is known about the population characteristics of patients who are recommended for echocardiographic examinations.

Methods

The National Ambulatory Medical Care Survey was a cross-sectional survey previously undertaken in the USA. In this study, publicly accessible data from the National Ambulatory Medical Care Survey database (for 2007-2016 and 2018-2019; data for 2017 was not published) were utilized to create a nomogram based on significant risk predictors. The study was performed in accordance with the relevant guidelines and regulations stipulated in the National Ambulatory Medical Care Survey database. Patients were randomly assigned to one of two groups: training cohort or validation cohort. The latter was used to assess the reliability of the prediction nomogram. Decision curve analysis was performed to evaluate the net benefit. Propensity score matching analysis was used to evaluate the relevance of echocardiography to clinical decision-making.

Results

A total of 217,178 outpatients were enrolled. Multivariable logistic regression analysis demonstrated that hypertension, hyperlipidemia, coronary artery disease/ischemic heart disease/history of myocardial infarction, congestive heart failure, major reason for visit, metropolitan statistical area, cerebrovascular disease/history of stroke or transient ischemic attack, previously assessed, insurance, referred, diagnosis, and reason for visit were all predictors of echocardiogram prescription in outpatients. The reliability of the predictive nomogram was confirmed in the validation cohort. After propensity score matching, there was a significant difference in new cardiovascular agent prescriptions between the echocardiogram and no echocardiogram groups (P < 0.01).

Conclusion

In this cohort study, a nomogram based on the characteristics of outpatients was developed to predict the possibility of prescribing echocardiography. The echocardiogram group was more likely to be prescribed new cardiovascular agents. These findings may contribute to providing information about the gap between actual utilizations and guidelines and the actual outpatient practice, as well as meeting the needs of outpatients.

Inferior vena cava diameter and risk of acute decompensated heart failure rehospitalisations

OBJECTIVES

Inferior vena cava (IVC) diameter may be a surrogate for volume status in acute decompensated heart failure (ADHF). The utility of IVC diameter measurement is under studied. The aim of this study was to assess the relationship between IVC diameter, clinical variables and ADHF rehospitalisations.

METHODS

Retrospective chart review of 200 patients admitted for ADHF from 2018 to 2019 with transthoracic echocardiogram during index hospitalisation. Charts were assessed for ADHF rehospitalisation within 1 year.

RESULTS

The median age was 64, 30.5% were female, and average left ventricular ejection fraction was 41%±20%. IVC diameter correlated to pulmonary arterial (PA) pressure (R=0.347, p<0.001) and body surface area (BSA) (R=0.424 p<0.001). IVC diameter corrected for BSA correlated to PA pressure (R=0.287, p<0.001) and log N-terminal B-type natriuretic peptide (NT-proBNP) (R=0.247, p≤0.01). Patients rehospitalised within 1 year had significantly greater mean IVC diameter compared with those not rehospitalised (p<0.001) while there was no difference in mean net weight lost during index hospitalisation or mean log NT-proBNP. Patients with IVC diameter greater than 2.07 cm had significantly increased ADHF rehospitalisation (85.6% vs 49.3%, log rank p<0.001) with HR 2.44 (95% CI 1.85 to 3.23, p<0.001). In multivariable Cox regression only IVC diameter (p<0.001), presence of tricuspid regurgitation (p=0.02) and NYHA class III/IV (p<0.001) independently predicted ADHF rehospitalisation within 1 year.

CONCLUSIONS

IVC diameter is predictive of rehospitalisation in patients with ADHF and may identify patients in need of greater monitoring and diuresis.

Validation of the MEDIA echo score for the prognosis of heart failure with preserved ejection fraction

There is currently no widely used prognostic score in heart failure (HF) with preserved ejection fraction (HFpEF). The MEDIA echo score, including four variables (pulmonary arterial systolic pressure > 40 mmHg, inferior vena cava collapsibility index < 50%, average E/e' > 9, and lateral mitral annular s' < 7 cm/s), has been proposed as a useful risk stratification tool. This study aimed at further validating the MEDIA echo score in both hospitalised and ambulatory HFpEF patients. The MEDIA echo score ranges from 0 to 4 (each criterion scores 1 point). The associations between MEDIA echo score and cardiovascular outcomes were assessed in two independent HFpEF cohorts, namely patients hospitalised for worsening HFpEF (N = 242, mean age 78 ± 11), and stable ambulatory HFpEF patients (N = 76, mean age 65 ± 8). Using multivariable Cox models, in the worsening HFpEF cohort, patients with a MEDIA echo score of 3-4 displayed a significant increased risk of death (HR 2.10, 95%CI 1.02-4.33, P = 0.043, score 0-1 as reference). In the ambulatory HFpEF cohort, patients with a MEDIA echo score of 2 had a significantly higher risk of death or HF hospitalisation (HR 3.44, 95%CI 1.27-9.30, P = 0.015, score 0 as reference), driven by HF hospitalisation; in that cohort, adding the MEDIA echo score to the clinical model significantly improved reclassification for the combined endpoint (integrated discrimination improvement 6.2%, P = 0.006). The MEDIA echo score significantly predicted the outcome of HFpEF patients in both hospital and ambulatory settings; its use may help refine routine risk stratification on top of well-established prognosticators in stable HFpEF patients.

Hospital at home for acute medical illness: The 21st century acute medical unit for a changing population

Recent trends across Europe show a year-on-year increase in the number of patients with acute medical illnesses presenting to hospitals, yet there are no plans for a substantial expansion in acute hospital infrastructure or staffing to address demand. Strategies to meet increasing demand need to consider the fact that there is limited capacity in acute hospitals and focus on new care models in both hospital and community settings. Increasing the efficiency of acute hospital provision by reducing the length of stay entails supporting acute ambulatory care, where patients receive daily acute care interventions but do not stay overnight in the hospitals. This approach may entail daily transfer between home and an acute setting for ongoing treatment, which is unsuitable for some patients living with frailty. Acute hospital at home (HaH) is a care model which, thanks to advances in point of care diagnostic capability, can provide a credible model of acute medical assessment and treatment without the need for hospital transfer. Investment and training to support scaling up of HaH are key strategic aims for integrated healthcare systems.

The value of the inferior vena cava ultrasound in the decision to hospitalise in patients with acute decompensated heart failure; the best sonographic measurement method?

OBJECTIVES

The primary aim of this study was to determine the value of the inferior vena cava (IVC) ultrasound in the decision to hospitalise acute decompensated heart failure (ADHF) patients. Our secondary aim was to find the most successful IVC measurement method in monitoring volume status.

METHODS

ADHF patients were accepted over a 1-year period in this study. Patients' vital signs, laboratory tests and IVC measurements measured by six methods (in B- and M-mode; maximum, minimum diameter and caval index) performed on an hourly basis were recorded. The presence of any statistically significant difference between the IVC measurement methods, laboratory tests and vital parameters between the hospitalised and discharged patients was calculated. ROC curves were produced in order to determine the ability of parameters to differentiate two groups. Spearman's correlation test was used to investigate correlation between the IVC measurement methods and patients' urine outputs.

RESULTS

A total of 71 patients were included in the study; 42 of these were hospitalised and 29 were discharged. Potassium, brain natriuretic peptide, respiration rate, urine output, maximum and minimum IVC diameters differed significantly between the two groups. Minimum IVC diameter measured in M-mode was identified as a weak marker with 65% sensitivity and 64% specificity (+PPV: 73%; -NPV:54%) for hospitalisation. Change in maximum IVC diameter measured in B-mode exhibited a high degree of correlation with change in body fluid (cc: 0.802).

CONCLUSION

IVC ultrasound may have a limited value in the decision to hospitalise ADHF patients. But Maximum IVC diameter may be an ideal method for monitoring hypervolemic patients' volume status.

CLINICAL TRIALS IDENTIFIER

NCT02725151.

Point of Care Ultrasonography for Objective Assessment of Heart Failure: Integration of Cardiac, Vascular, and Extravascular Determinants of Volume Status

BACKGROUND

Lingering congestion portends poor outcomes in patients with heart failure (HF) and is a key target in their management. Studies have shown that physical exam has low yield in this setting and conventional methods for more precise assessment and monitoring of volume status (e.g., body weight, natriuretic peptides, and chest radiography) have significant inherent shortcomings.

SUMMARY

Point of care ultrasonography (POCUS) is a noninvasive versatile bedside diagnostic tool that enhances the sensitivity of conventional physical examination to gauge congestion in these patients. It also aids in monitoring the efficacy of decongestive therapy and bears prognostic significance. In this narrative review, we discuss the role of focused sonographic assessment of the heart, venous system, and extravascular lung water/ascites (i.e., the pump, pipes, and the leaks) in objective assessment of fluid volume status. Key Messages: Since each of the discussed components of POCUS has its limitations, a combinational ultrasound evaluation guided by the main clinical features would be the key to reliable assessment and effective management of congestion in patients with HF.

Ultrasound imaging of congestion in heart failure: examinations beyond the heart

Congestion, related to pressure and/or fluid overload, plays a central role in the pathophysiology, presentation and prognosis of heart failure and is an important therapeutic target. While symptoms and physical signs of fluid overload are required to make a clinical diagnosis of heart failure, they lack both sensitivity and specificity, which might lead to diagnostic delay and uncertainty. Over the last decades, new ultrasound methods for the detection of elevated intracardiac pressures and/or fluid overload have been developed that are more sensitive and specific, thereby enabling earlier and more accurate diagnosis and facilitating treatment strategies. Accordingly, we considered that a state-of-the-art review of ultrasound methods for the detection and quantification of congestion was timely, including imaging of the heart, lungs (B-lines), kidneys (intrarenal venous flow), and venous system (inferior vena cava and internal jugular vein diameter).

Diagnosis of Acute Heart Failure Using Inferior Vena Cava Ultrasound: Systematic Review and Meta-analysis

OBJECTIVES

The utility of bedside inferior vena cava (IVC) ultrasound (US) in the diagnosis of heart failure (HF) is unclear. The aim of this study was to determine whether IVC parameters in patients with acute heart failure (AHF) are statistically different from those without HF.

METHODS

The MEDLINE database of English-language publications from 1966 to August 2018 was searched. Retrospective and prospective studies that included either IVC expiratory diameter (IVC_exp ) or IVC collapsibility index (IVC-CI) values were collected in patients with and without HF. to determine whether there was a statistical difference in the IVC parameters between these groups.

RESULTS

A total of 27 articles with a total of 1472 patients with AHF were included. The standard mean differences for the IVC_exp and IVC-CI for the control group versus the AHF group were found to be statistically significant (P < .0001). The combined mean IVC_exp values were 15.11 mm (95% confidence interval [CI], 14.19-16.02 mm) for the control group and 20.26 mm (95% CI, 14.82-25.71 mm) for the AHF group. The combined mean IVC-CI values were 61.6% (95% CI, 48.4%-74.7%) for the control group and 30.5% (95% CI, 26.4%-34.6%) for the AHF group.

CONCLUSIONS

Bedside IVC US showed that a statistically significant difference existed in the IVC parameters between patients with and without AHF. Based on mean calculations, an IVC_exp of greater than 2.0 cm and an IVC-CI of less than 30% are reasonable cutoffs to suggest that a patient with acute dyspnea is more likely to have AHF than a non-AHF condition. Given the high degree of heterogeneity across the studies and the high risk of bias, larger randomized studies are warranted to explore the use of IVC US in patients with HF.

Point-of-care ultrasound modalities in terms of diagnosing acute decompensated heart failure in emergency department; a diagnostic accuracy study

This study aimed to compare the diagnostic accuracy of heart, lung and inferior vena cava (IVC) ultrasonography modalities, alone and combined, for possible added accuracy in diagnosing acute decompensated heart failure (ADHF), in a group of patients with the final diagnosis of ADHF based on plasma level of B-type natriuretic peptide (BNP) as the standard. The present study is a diagnostic accuracy study, which was carried out in the emergency department of Imam Khomeini hospital, affiliated to Tehran University of Medical Sciences, in 2014-2015. All patients over 18 years old, who were referred to emergency department with complaint of acute dyspnea were regarded as eligible and no exclusion criteria were considered. All ultrasounds were performed by a trained emergency medicine resident and then saved and classified for each patient, separately, and reviewed by the attending emergency medicine physician. In this study, patients with BNP levels higher than 500 pg/ml were considered positive for dyspnea caused by heart failure. A total of 120 patients with an average age of 60.83 ± 16.528 years were studied, 64 (53%) of which were male. In total, 47.5% of patients had a BNP level over 500 pg/ml. Among patients with positive ultrasound, 94.7% were true positive and among those with a negative ultrasound, 61.4% were true negative. Based on the findings, B-line ≥ 10 has the highest specificity and left ventricular ejection fraction (LVEF) < 45% has the highest sensitivity. The combination of LVEF and IVC collapsibility index (IVC-CI), LVEF and BLC, IVC-CI and BLC, and IVC-CI and BBPC had a higher specificity rate and combination of LVEF and BBPC and BLC and BBPC had the highest sensitivity. Sensitivity, specificity, positive predictive value and negative predictive value of all three ultrasounds combined were 31.6%, 98.4%, 94.7% and 61.4%, respectively. In this study, the diagnostic accuracy of double and triple ultrasonography of heart, lung and IVC in the diagnosis of ADHF was very high, among which triple ultrasonography was more preferable.

Accuracy of Several Lung Ultrasound Methods for the Diagnosis of Acute Heart Failure in the ED: A Multicenter Prospective Study

BACKGROUND

Early appropriate diagnosis of acute heart failure (AHF) is recommended by international guidelines. This study assessed the value of several lung ultrasound (LUS) strategies for identifying AHF in the ED.

METHODS

This prospective study, conducted in four EDs, included patients with diagnostic uncertainty based on initial clinical judgment. A clinical diagnosis score for AHF (Brest score) was quantified, followed by an extensive LUS examination performed according to the 4-point (BLUE protocol) and 6-, 8-, and 28-point methods. The primary outcome was AHF discharge diagnosis adjudicated by two senior physicians blinded to LUS measurements. The C-index was used to quantify discrimination.

RESULTS

Among the 117 included patients, AHF (n = 69) was identified in 27.4%, 56.2%, 54.8%, and 76.7% of patients with the 4-point (two bilateral positive points), 6-point, 8-point (≥ 1 bilateral positive point), and 28-point (B-line count ≥ 30) methods, respectively. The C-index (95% CI) of the Brest score was 72.8 (65.3-80.3), whereas the C-index of the 4-, 6-, 8-, and 28-point methods were 63.7 (58.5-68.8), 72.4 (65.0-79.8), 74.0 (67.1-80.9), and 72.4 (63.9-80.9). The highest increase in the C-index on top of the BREST score was observed with the 8-point method in the whole population (6.9; 95% CI, 1.6-12.2; P = .010) and in the population with an intermediate Brest score, followed by the 6-point method.

CONCLUSIONS

In patients with diagnostic uncertainty, the 6-point/8-point LUS method (using the 1 bilateral positive point threshold) improves AHF diagnosis accuracy on top of the BREST score.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT03194243; URL: www.clinicaltrials.gov.