Primary care REFerral for EchocaRdiogram (REFER) in heart failure: a diagnostic accuracy study

Diagnostic properties of natriuretic peptides and opportunities for personalized thresholds for detecting heart failure in primary care

OBJECTIVES

Heart failure (HF) is a prevalent syndrome with considerable disease burden, healthcare utilization and costs. Timely diagnosis is essential to improve outcomes. This study aimed to compare the diagnostic performance of B-type natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) in detecting HF in primary care. Our second aim was to explore if personalized thresholds (using age, sex, or other readily available parameters) would further improve diagnostic accuracy over universal thresholds.

METHODS

A retrospective study was performed among patients without prior HF who underwent natriuretic peptide (NP) testing in the Amsterdam General Practice Network between January 2011 and December 2021. HF incidence was based on registration out to 90 days after NP testing. Diagnostic accuracy was evaluated with AUROC, sensitivity and specificity based on guideline-recommended thresholds (125 ng/L for NT-proBNP and 35 ng/L for BNP). We used inverse probability of treatment weighting to adjust for confounding.

RESULTS

A total of 15,234 patients underwent NP testing, 6,870 with BNP (4.5 % had HF), and 8,364 with NT-proBNP (5.7 % had HF). NT-proBNP was more accurate than BNP, with an AUROC of 89.9 % (95 % CI: 88.4-91.2) vs. 85.9 % (95 % CI 83.5-88.2), with higher sensitivity (95.3 vs. 89.7 %) and specificity (59.1 vs. 58.0 %). Differentiating NP cut-off by clinical variables modestly improved diagnostic accuracy for BNP and NT-proBNP compared with a universal threshold.

CONCLUSIONS

NT-proBNP outperforms BNP for detecting HF in primary care. Personalized instead of universal diagnostic thresholds led to modest improvement.

To support the use of NT-proBNP to better detect heart failure in patients with type 2 diabetes

PURPOSE

Heart failure (HF) is a chronic disease that causes approximately 300,000 and 250,000 deaths per year in Europe and United States, respectively. Type 2 Diabetes Mellitus (T2DM) is one the major risk factors of HF, and the investigation of NT-proBNP might support the early identification of HF in T2DM sufferers. Nevertheless, this parameter is poorly investigated. Thus, we aimed to demographically and clinically characterize diabetic patients which were prescribed with NT-proBNP in the primary care setting.

METHODS

Using a primary care database, we formed a cohort of patients aged ≥18 years diagnosed with T2DM between 2002 and 2021. A multivariate Cox model was adopted to assess the determinants associated with the prescription of NT-proBNP.

RESULTS

Among 167,961 T2DM patients, 7558 (4.5%, 95% CI: 4.4-4.6) were prescribed with NT-proBNP. Males and increasing age were expectedly associated with a higher propensity to be prescribed with NT-proBNP. In addition, a significant association was found for those suffering from obesity, ischemic cardiomyopathy, stroke, atrial fibrillation, hypertension, and with a Charlson Index of 2+.

CONCLUSION

These determinants might contribute to investigate the NT-proBNP in T2DM sufferers. A decision support system to appropriately ease the prescription of NT-proBNP might be therefore implemented in primary care settings.

Heart failure diagnosis in the general community - Who, how and when? A clinical consensus statement of the Heart Failure Association (HFA) of the European Society of Cardiology (ESC)

A significant proportion of patients experience delays in the diagnosis of heart failure due to the non-specific signs and symptoms of the syndrome. Diagnostic tools such as measurement of natriuretic peptide concentrations are fundamentally important when screening for heart failure, yet are frequently under-utilized. This clinical consensus statement provides a diagnostic framework for general practitioners and non-cardiology community-based physicians to recognize, investigate and risk-stratify patients presenting in the community with possible heart failure.

Natriuretic peptide testing and heart failure diagnosis in primary care: diagnostic accuracy study

BACKGROUND

Natriuretic peptide (NP) testing is recommended for patients presenting to primary care with symptoms of chronic heart failure (HF) to prioritise referral for diagnosis.

AIM

To report NP test performance at European Society of Cardiology (ESC) and National Institute for Health and Care Excellence (NICE) guideline referral thresholds.

DESIGN AND SETTING

Diagnostic accuracy study using linked primary and secondary care data (2004 to 2018).

METHOD

The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of NP testing for HF diagnosis was assessed.

RESULTS

In total, 229 580 patients had an NP test and 21 102 (9.2%) were diagnosed with HF within 6 months. The ESC NT-proBNP threshold ≥125 pg/mL had a sensitivity of 94.6% (95% confidence interval [CI] = 94.2 to 95.0) and specificity of 50.0% (95% CI = 49.7 to 50.3), compared with sensitivity of 81.7% (95% CI = 81.0 to 82.3) and specificity of 80.3% (95% CI = 80.0 to 80.5) for the NICE NT-proBNP ≥400 pg/mL threshold. PPVs for an NT-proBNP test were 16.4% (95% CI = 16.1 to 16.6) and 30.0% (95% CI = 29.6 to 30.5) for ESC and NICE thresholds, respectively. For both guidelines, nearly all patients with an NT-proBNP level below the threshold did not have HF (NPV: ESC 98.9%, 95% CI = 98.8 to 99.0 and NICE 97.7%, 95% CI = 97.6 to 97.8).

CONCLUSION

At the higher NICE chronic HF guideline NP thresholds, one in five cases are initially missed in primary care but the lower ESC thresholds require more diagnostic assessments. NP is a reliable 'rule-out' test at both cut-points. The optimal NP threshold will depend on the priorities and capacity of the healthcare system.

Reference Ranges for NT-proBNP (N-Terminal Pro-B-Type Natriuretic Peptide) and Risk Factors for Higher NT-proBNP Concentrations in a Large General Population Cohort

BACKGROUND

Demographic differences in expected NT-proBNP (N-terminal pro-B-type natriuretic peptide) concentration are not well established. We aimed to establish reference ranges for NT-proBNP and explore the determinants of moderately elevated NT-proBNP under the universal definition of heart failure criteria.

METHODS

This is a cross-sectional study. NT-proBNP was measured in serum from 18 356 individuals without previous cardiovascular disease in the Generation Scotland Scottish Family Health Study. Age- and sex-stratified medians and 97.5th centiles were generated. Sex stratified risk factors for moderately elevated NT-proBNP (≥125 pg/mL) were investigated.

RESULTS

In males, median (97.5th centile) NT-proBNP concentration at age <30 years was 21 (104) pg/mL, rising to 38 (195) pg/ml at 50 to 59 years, and 281 (6792) pg/mL at ≥80 years. In females, median NT-proBNP at age <30 years was 51 (196) pg/mL, 66 (299) pg/mL at 50 to 59 years, and 240 (2704) pg/mL at ≥80 years. At age <30 years, 9.8% of females and 1.4% of males had elevated NT-proBNP, rising to 76.5% and 81.0%, respectively, at age ≥80 years. After adjusting for risk factors, an NT-proBNP ≥125 pg/mL was more common in females than males (OR, 9.48 [95% CI, 5.60-16.1]). Older age and smoking were more strongly associated with elevated NT-proBNP in males than in females (Psex interaction <0.001, 0.07, respectively). Diabetes was inversely associated with odds of elevated NT-proBNP in females only (Psex interaction=0.007).

CONCLUSIONS

An NT-proBNP ≥125 pg/mL is common in females without classical cardiovascular risk factors as well as older people. If NT-proBNP becomes widely used for screening in the general population, interpretation of NT-proBNP levels will require that age and sex-specific thresholds are used to identify patients with potential pathophysiology.

Feasibility of the cardiac output response to stress test in suspected heart failure patients

BACKGROUND

Diagnostic tools available to support general practitioners diagnose heart failure (HF) are limited.

OBJECTIVES

(i) Determine the feasibility of the novel cardiac output response to stress (CORS) test in suspected HF patients, and (ii) Identify differences in the CORS results between (a) confirmed HF patients from non-HF patients, and (b) HF reduced (HFrEF) vs HF preserved (HFpEF) ejection fraction.

METHODS

Single centre, prospective, observational, feasibility study. Consecutive patients with suspected HF (N = 105; mean age: 72 ± 10 years) were recruited from specialized HF diagnostic clinics in secondary care. The consultant cardiologist confirmed or refuted a HF diagnosis. The patient completed the CORS but the researcher administering the test was blinded from the diagnosis. The CORS assessed cardiac function (stroke volume index, SVI) noninvasively using the bioreactance technology at rest-supine, challenge-standing, and stress-step exercise phases.

RESULTS

A total of 38 patients were newly diagnosed with HF (HFrEF, n = 21) with 79% being able to complete all phases of the CORS (91% of non-HF patients). A 17% lower SVI was found in HF compared with non-HF patients at rest-supine (43 ± 15 vs 51 ± 16 mL/beat/m2, P = 0.02) and stress-step exercise phase (49 ± 16 vs 58 ± 17 mL/beat/m2, P = 0.02). HFrEF patients demonstrated a lower SVI at rest (39 ± 15 vs 48 ± 13 mL/beat/m2, P = 0.02) and challenge-standing phase (34 ± 9 vs 42 ± 12 mL/beat/m2, P = 0.03) than HFpEF patients.

CONCLUSION

The CORS is feasible and patients with HF responded differently to non-HF, and HFrEF from HFpEF. These findings provide further evidence for the potential use of the CORS to improve HF diagnostic and referral accuracy in primary care.

2021 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure: Developed by the Task Force for the diagnosis and treatment of acute and chronic heart failure of the European Society of Cardiology (ESC). With the special contribution of the Heart Failure Association (HFA) of the ESC

Document Reviewers: Rudolf A. de Boer (CPG Review Coordinator) (Netherlands), P. Christian Schulze (CPG Review Coordinator) (Germany), Magdy Abdelhamid (Egypt), Victor Aboyans (France), Stamatis Adamopoulos (Greece), Stefan D. Anker (Germany), Elena Arbelo (Spain), Riccardo Asteggiano (Italy), Johann Bauersachs (Germany), Antoni Bayes-Genis (Spain), Michael A. Borger (Germany), Werner Budts (Belgium), Maja Cikes (Croatia), Kevin Damman (Netherlands), Victoria Delgado (Netherlands), Paul Dendale (Belgium), Polychronis Dilaveris (Greece), Heinz Drexel (Austria), Justin Ezekowitz (Canada), Volkmar Falk (Germany), Laurent Fauchier (France), Gerasimos Filippatos (Greece), Alan Fraser (United Kingdom), Norbert Frey (Germany), Chris P. Gale (United Kingdom), Finn Gustafsson (Denmark), Julie Harris (United Kingdom), Bernard Iung (France), Stefan Janssens (Belgium), Mariell Jessup (United States of America), Aleksandra Konradi (Russia), Dipak Kotecha (United Kingdom), Ekaterini Lambrinou (Cyprus), Patrizio Lancellotti (Belgium), Ulf Landmesser (Germany), Christophe Leclercq (France), Basil S. Lewis (Israel), Francisco Leyva (United Kingdom), AleVs Linhart (Czech Republic), Maja-Lisa Løchen (Norway), Lars H. Lund (Sweden), Donna Mancini (United States of America), Josep Masip (Spain), Davor Milicic (Croatia), Christian Mueller (Switzerland), Holger Nef (Germany), Jens-Cosedis Nielsen (Denmark), Lis Neubeck (United Kingdom), Michel Noutsias (Germany), Steffen E. Petersen (United Kingdom), Anna Sonia Petronio (Italy), Piotr Ponikowski (Poland), Eva Prescott (Denmark), Amina Rakisheva (Kazakhstan), Dimitrios J. Richter (Greece), Evgeny Schlyakhto (Russia), Petar Seferovic (Serbia), Michele Senni (Italy), Marta Sitges (Spain), Miguel Sousa-Uva (Portugal), Carlo G. Tocchetti (Italy), Rhian M. Touyz (United Kingdom), Carsten Tschoepe (Germany), Johannes Waltenberger (Germany/Switzerland) All experts involved in the development of these guidelines have submitted declarations of interest. These have been compiled in a report and published in a supplementary document simultaneously to the guidelines. The report is also available on the ESC website www.escardio.org/guidelines For the Supplementary Data which include background information and detailed discussion of the data that have provided the basis for the guidelines see European Heart Journal online.

Assessment of the impact of different N terminal pro brain natriuretic peptide thresholds on echocardiography services

Aims

N terminal pro brain natriuretic peptide (NT‐proBNP) is considered a rule‐out test for patients with suspected heart failure. The NT‐proBNP thresholds recommended for echocardiography by the European Society of Cardiology (ESC) and National Institute for Health and Care Excellence (NICE) are based on small studies of patients with heart failure and left ventricular (LV) systolic dysfunction (LVSD). The purpose of our study was to examine the relation between NT‐proBNP and LVSD in a larger number of patients with symptoms suggestive of heart failure in a non‐acute setting.

Methods and results

One thousand patients with suspected chronic heart failure underwent echocardiography within 6 months of NT‐proBNP measurement. NT‐proBNP was the strongest predictor of any form of LVSD in univariate (OR 2.52, 95% CI 2.19–2.91, P value < 0.001) and multivariate (OR 2.73, 95% CI 2.32–3.21, P value < 0.001) analyses. Negative predictive value (NPV) of NT‐proBNP for impaired LV systolic function (ejection fraction 35–49%) was 98% at 125 pg/mL (the ESC threshold), 93% at 400 pg/mL (the NICE threshold), 91% at 1000 pg/mL and 90% at 2000 pg/mL. Corresponding values for severe LVSD (ejection fraction <35%) were 100%, 99%, 98% and 96%. The number of patients per 1000 with suspected chronic heart failure requiring echocardiography at each threshold was 851, 543, 324, and 182, respectively.

Conclusions

N terminal pro brain natriuretic peptide thresholds recommended by ESC and NICE result in large numbers of patients with suspected chronic heart failure being referred for echocardiography. Raising the NT‐proBNP threshold would improve access to echocardiography with minimal negative impact on the clinical performance of this cardiac biomarker.

Diagnosing heart failure in primary care: individual patient data meta-analysis of two European prospective studies

Aims

Natriuretic peptides are helpful in detecting chronic heart failure (HF) in primary care; however, there are a lack of data evaluating thresholds recommended by clinical guidelines. This study assesses the diagnostic accuracy of N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP) using combined individual patient data from two studies in the UK and the Netherlands.

Methods and results

Random effects methods were used to estimate the performance characteristics of NT‐proBNP thresholds recommended by the European Society of Cardiology (ESC) and the UK National Institute for Health and Care Excellence (NICE) guidelines. New onset HF was diagnosed in 313 of 1073 (29.2%) participants. Age, sex, and atrial fibrillation‐adjusted NT‐proBNP was a better predictor of HF with reduced ejection fraction (HFrEF) than HF preserved ejection fraction (HFpEF), with area under receiver operating characteristic curve of 0.82 95% CI (0.78 to 0.86) vs. 0.71 (0.66 to 0.75). In persons aged 70 years and over, the ESC threshold at 125 ng/L for detection of all‐cause HF had summary negative predictive value (NPV) of 84.9% (81.6 to 88.2), positive predictive value (PPV) 68.1% (63.1 to 73.3), sensitivity 74.9% (69.5 to 80.3), and specificity 80.1% (76.9 to 83.4); the NICE threshold at 400 ng/L had summary NPV of 74.7% (72.1 to 77.2), PPV 81.8% (73.3 to 89.5), sensitivity 43.5% (37.2 to 49.8), and specificity 94.5% (92.3 to 96.7).

Conclusions

N‐terminal pro‐B‐type natriuretic peptide is better at detecting HFrEF than HFpEF in a primary care setting. In persons aged 70 and over, the ESC threshold of 125 ng/L is more accurate at detecting and excluding HF than the higher level suggested in NICE guidelines. More prospective data are required to establish the optimal NP threshold for detecting chronic HF in general practice.

Characterisation of the patients with suspected heart failure: experience from the SHEAF registry

OBJECTIVES

To characterise and risk-stratify patients presenting to a heart failure (HF) clinic according to the National Institute for health and Care Excellence (NICE) algorithm.

METHODS

This is an observational study of prospectively collected data in the Sheffield HEArt Failure registry of consecutive patients with suspected HF between April 2012 and January 2020. Outcome was defined as all-cause mortality.

RESULTS

6144 patients were enrolled: 71% had HF and 29% had no HF. Patients with N-terminal pro-brain-type natriuretic peptide (NT-proBNP) >2000 pg/mL were more likely to have HF than those with NT-proBNP of 400-2000 pg/mL (92% vs 64%, respectively). Frequency of HF phenotypes include: HF with preserved ejection fraction (HFpEF) (33%), HF with reduced ejection fraction (HFrEF) (29%), HF due to valvular heart disease (4%), HF due to pulmonary hypertension (5%) and HF due to right ventricular systolic dysfunction (1%). There were 1485 (24%) deaths over a maximum follow-up of 6 years. The death rate was higher in HF versus no HF (11.49 vs 7.29 per 100 patient-years follow-up, p<0.0001). Patients with HF and an NT-proBNP >2000 pg/mL had lower survival than those with NT-proBNP 400-2000 pg/mL (3.8 years vs 5 years, p<0.0001). Propensity matched survival curves were comparable between HFpEF and HFrEF (p=0.88).

CONCLUSION

Our findings support the use by NICE's HF diagnostic algorithm of tiered triage of patients with suspected HF based on their NT-proBNP levels. The two pathways yielded distinctive groups of patients with varied diagnoses and prognosis. HFpEF is the most frequent diagnosis, with its challenges of poor prognosis and paucity of therapeutic options.

Point-of-care testing of (N-terminal pro) B-type natriuretic peptide for heart disease patients in home care and ambulatory care settings

Objectives

The role of point-of-care testing (POCT) out of hospital, especially in home care and ambulatory care settings, is an issue meriting further research. We reviewed studies reporting cardiovascular events as a result of the implementation of B-type natriuretic peptide or N-terminal pro B-type natriuretic peptide POCT (BNP/NT-proBNP POCT) for heart disease patients in the settings.

Design

Articles were searched via a PubMed engine until May 30, 2020.

Results

In total, six studies were selected. Three studies involving ambulatory care used the POCT to refer patients with suspected heart diseases to a specialist. The other three used the tests in home care to monitor patients with heart failure. In ambulatory care, the randomized controlled trials, in which referrals were made to a specialist, showed that the group using POCT had significantly fewer cardiovascular outcomes, such as hospitalizations and deaths, than the non-use group. In home care, adverse outcomes were predicted from changes in BNP levels.

Conclusions

In most studies, the use of BNP/NT-proBNP POCT in home care and ambulatory care settings demonstrated favorable results regarding the cardiovascular outcomes. The utility of POCT in the settings is suggested, while more investigations are required.

•

Point-of-care testing of BNP can be useful for referral of patients to specialists as demonstrated in two randomized control trials.

•

Point-of-care testing of BNP couldpredict acute heart failure as demonstrated in three observational studies.

•

The findings should be generalized with care because of the limitation of available data.

Time trends in the use and appropriateness of natriuretic peptide testing in primary care: an observational study

Background

Diagnosing heart failure (HF) is difficult, relying on medical history, symptoms, and signs only. Clinical guidelines recommend natriuretic peptides (NPs) as an additional diagnostic test, notably to exclude HF in suspected patients. NP testing has been available since 2003 for primary care in the Netherlands, but little is known about its uptake.

Aim

To evaluate the trend in ordering and appropriateness of NP testing in primary care.

Design & setting

An observational study was performed between January 2005 and December 2013. Nine Dutch general practices participated, with 21 000 registered people (approximately 4300 aged ≥65 years).

Method

The total number of patients undergoing NP testing each year was calculated per 1000 patient years (PY) based on the total practice population. NP levels were used to assess whether NP testing was applied to exclude or confirm HF.

Results

The number of NP testing increased from 2.5 per 1000 PY in 2005 to 14.0 per 1000 PY in 2013, with a peak in 2009 of 15.6 per 1000 PY. The proportion of participants with N-terminal B-type natriuretic peptide (NTproBNP) below 125 pg/ml (the exclusionary threshold recommended by the European Society of Cardiology [ESC] guidelines on HF) was on average 30%, and highest in the first year (47%).

Conclusion

After a rapid uptake of NP testing in primary care from 2005 onwards, the use of it seemed to stabilise after 2009, thus leaving patients who are prone to HF without an optimal diagnostic work-up.

Cardiac biomarkers in patients with prostate cancer and cardiovascular disease receiving gonadotrophin releasing hormone agonist vs antagonist

BACKGROUND

Gonadotrophin releasing hormone (GnRH) agonists and antagonists reduce testosterone levels for the treatment of advanced and metastatic prostate cancer. Androgen deprivation therapy (ADT) is associated with increased risk of cardiovascular (CV) events and CV disease (CVD), especially in patients with preexisting CVD treated with GnRH agonists. Here, we investigated the potential relationship between serum levels of the cardiac biomarkers N-terminal pro-B-type natriuretic peptide (NTproBNP), D-dimer, C-reactive protein (CRP), and high-sensitivity troponin (hsTn) and the risk of new CV events in prostate cancer patients with a history of CVD receiving a GnRH agonist or antagonist.

METHODS

Post-hoc analyses were performed of a phase II randomized study that prospectively assessed CV events in patients with prostate cancer and preexisting CVD, receiving GnRH agonist or antagonist. Cox proportional hazards models were used to determine whether the selected biomarkers had any predictive effect on CV events at baseline and across a 12-month treatment period.

RESULTS

Baseline and disease characteristics of the 80 patients who took part in the study were well balanced between treatment arms. Ischemic heart disease (66%) and myocardial infarction (37%) were the most common prior CVD and the majority (92%) of patients received CV medication. We found that high levels of NTproBNP (p = 0.008), and hsTn (p = 0.004) at baseline were associated with the development of new CV events in the GnRH agonist group but not in the antagonist. In addition, a nonsignificant trend was observed between higher levels of NTproBNP over time and the development of new CV events in the GnRH agonist group.

CONCLUSIONS

The use of cardiac biomarkers may be worthy of further study as tools in the prediction of CV risk in prostate cancer patients receiving ADT. Analysis was limited by the small sample size; larger studies are required to validate biomarker use to predict CV events among patients receiving ADT.

Prospective evaluation and long-term follow-up of patients referred to secondary care based upon natriuretic peptide levels in primary care

AIMS

The UK National Institute for Health and Care Excellence (UK-NICE) and European Society of Cardiology (ESC) guidelines advise natriuretic peptide (NP) assessment in patients presenting to primary care with symptoms possibly due to chronic heart failure (HF), to determine need for specialist involvement. This prospective service evaluation aimed to describe the diagnostic and prognostic utility of these guidelines.

METHODS AND RESULTS

We prospectively collected clinical, echocardiography and outcomes data (minimum 5 years) from all patients referred to the Leeds HF Service for 12 months of following the initiation of the NP-guideline-directed pathway. Between 1 May 2012 and 1 August 2013, 1020 people with symptoms possibly due to HF attended either with a raised NT-pro-BNP or a previous myocardial infarction (MI) with an overall rate of left ventricular systolic dysfunction (LVSD) of 33%. Of these, 991 satisfied the ESC criteria (NT-pro-BNP ≥125 pg/mL) in whom the rate of LVSD was 32%, and 821 the UK-NICE criteria in whom the rate of LVSD was 49% in those with a previous MI, 25% in those with NT-pro-BNP concentration 400-2000 pg/mL, and 54% in those with NT-pro-BNP concentration of >2000 pg/mL. An NT-pro-BNP concentration 125-400 pg/mL had a 12% risk of LVSD. Specificity was poor in women >70 years, who made up the largest proportion of attendees. Elevated NT-pro-BNP levels were associated with lower survival even in the absence of LVSD.

CONCLUSION

In people referred through the ESC and UK-NICE guidelines, elevated NT-pro-BNP is a marker of increased mortality risk, but there is wide variation in specificity for LVSD. Age- and sex-adjusted criteria might improve performance.

Opportunities and challenges of a novel cardiac output response to stress (CORS) test to enhance diagnosis of heart failure in primary care: qualitative study

OBJECTIVE

To explore the role of the novel cardiac output response to stress (CORS), test in the current diagnostic pathway for heart failure and the opportunities and challenges to potential implementation in primary care.

DESIGN

Qualitative study using semistructured in-depth interviews which were audio recorded and transcribed verbatim. Data from the interviews were analysed thematically using an inductive approach.

SETTING

Newcastle upon Tyne, UK.

PARTICIPANTS

Fourteen healthcare professionals (six males, eight females) from primary (general practitioners (GPs), nurses, healthcare assistant, practice managers) and secondary care (consultant cardiologists).

RESULTS

Four themes relating to opportunities and challenges surrounding the implementation of the new diagnostic technology were identified. These reflected that the adoption of CORS test would be an advantage to primary care but the test had barriers to implementation which include: establishment of clinical utility, suitability for immobile patients and cost implication to GP practices.

CONCLUSION

The development of a simple non-invasive clinical test to accelerate the diagnosis of heart failure in primary care maybe helpful to reduce unnecessary referrals to secondary care. The CORS test has the potential to serve this purpose; however, factors such as cost effectiveness, diagnostic accuracy and seamless implementation in primary care have to be fully explored.

A systematic review of clinical prediction rules for the diagnosis of chronic heart failure

Aims

This study sought to review the literature for clinical prediction models for the diagnosis of patients with chronic heart failure in the community and to validate the models in a novel cohort of patients with a suspected diagnosis of chronic heart failure.

Methods and results

MEDLINE and Embase were searched from 1946 to Q4 2017. Studies were eligible if they contained at least one multivariable model for the diagnosis of chronic heart failure applicable to the primary care setting. The CHARMS checklist was used to evaluate models. We also validated models, where possible, in a novel cohort of patients with a suspected diagnosis of heart failure referred to a rapid access diagnostic clinic.

In total, 5310 articles were identified with nine articles subsequently meeting the eligibility criteria. Three models had undergone internal validation, and four had undergone external validation. No clinical impact studies have been completed to date. Area under the curve (AUC) varied from 0.74 to 0.93 and from 0.60 to 0.65 in the novel cohort for clinical models alone with AUC up to 0.89 in combination with electrocardiogram and B‐type natriuretic peptide (BNP). The AUC for BNP was 0.86 (95% confidence interval 83.3–88.6%).

Conclusions

This review demonstrates that there are a number of clinical prediction rules relevant to the diagnosis of chronic heart failure in the literature. Clinical impact studies are required to compare the use of clinical prediction rules and biomarker strategies in this setting.

A novel cardiac output response to stress test developed to improve diagnosis and monitoring of heart failure in primary care

AIMS

Primary care physicians lack access to an objective cardiac function test. This study for the first time describes a novel cardiac output response to stress (CORS) test developed to improve diagnosis and monitoring of heart failure in primary care and investigates its reproducibility.

METHODS AND RESULTS

Prospective observational study recruited 32 consecutive primary care patients (age, 63 ± 9 years; female, n = 18). Cardiac output was measured continuously using the bioreactance method in supine and standing positions and during two 3 min stages of a step-exercise protocol (10 and 15 steps per minute) using a 15 cm height bench. The CORS test was performed on two occasions, i.e. Test 1 and Test 2. There was no significant difference between repeated measures of cardiac output and stroke volume at supine standing and Stage 1 and Stage 2 step exercises (all P > 0.3). There was a significant positive relationship between Test 1 and Test 2 cardiac outputs (r = 0.92, P = 0.01 with coefficient of variation of 7.1%). The mean difference in cardiac output (with upper and lower limits of agreement) between Test 1 and Test 2 was 0.1 (-1.9 to 2.1) L/min, combining supine, standing, and step-exercise data.

CONCLUSIONS

The CORS, as a novel test for objective evaluation of cardiac function, demonstrates acceptable reproducibility and can potentially be implemented in primary care.

Breathlessness in the primary care setting

PURPOSE OF REVIEW

Breathlessness is a high-volume problem with 10% of adults experiencing the symptom daily placing a heavy burden on the health and wider economy. As it worsens, they enter the specialist and hospital-based symptom services where costs quickly escalate and people may find themselves in a place not of their choosing. For many, their care will be delivered by a disease or organ specialist and can find themselves passing between physicians without coordination for symptom support. General practitioners (GPs) will be familiar with this scenario and can often feel out of their depth. Recent advances in our thinking about breathlessness symptom management can offer opportunities and a sense of hope when the GP is faced with this situation.

RECENT FINDINGS

Original research, reviews and other findings over the last 12-18 months that pertain to the value that general practice and the wider primary care system can add, include opportunities to help people recognize they have a problem that can be treated. We present systems that support decisions made by primary healthcare professionals and an increasingly strong case that a solution is required in primary care for an ageing and frail population where breathlessness will be common.

SUMMARY

Primary care practitioners and leaders must start to realize the importance of recognizing and acting early in the life course of the person with breathlessness because its impact is enormous. They will need to work closely with public health colleagues and learn from specialists who have been doing this work usually with people near to the end of life translating the skills and knowledge further upstream to allow people to live well and remain near home and in their communities.

Diagnostic accuracy of point-of-care natriuretic peptide testing for chronic heart failure in ambulatory care: systematic review and meta-analysis

OBJECTIVE

To assess the diagnostic accuracy of point-of-care natriuretic peptide tests in patients with chronic heart failure, with a focus on the ambulatory care setting.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Ovid Medline, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Embase, Health Technology Assessment Database, Science Citation Index, and Conference Proceedings Citation Index until 31 March 2017.

STUDY SELECTION

Eligible studies evaluated point-of-care natriuretic peptide testing (B-type natriuretic peptide (BNP) or N terminal fragment pro B-type natriuretic peptide (NTproBNP)) against any relevant reference standard, including echocardiography, clinical examination, or combinations of these, in humans. Studies were excluded if reported data were insufficient to construct 2×2 tables. No language restrictions were applied.

RESULTS

42 publications of 39 individual studies met the inclusion criteria and 40 publications of 37 studies were included in the analysis. Of the 37 studies, 30 evaluated BNP point-of-care testing and seven evaluated NTproBNP testing. 15 studies were done in ambulatory care settings in populations with a low prevalence of chronic heart failure. Five studies were done in primary care. At thresholds >100 pg/mL, the sensitivity of BNP, measured with the point-of-care index device Triage, was generally high and was 0.95 (95% confidence interval 0.90 to 0.98) at 100 pg/mL. At thresholds <100 pg/mL, sensitivity ranged from 0.46 to 0.97 and specificity from 0.31 to 0.98. Primary care studies that used NTproBNP testing reported a sensitivity of 0.99 (0.57 to 1.00) and specificity of 0.60 (0.44 to 0.74) at 135 pg/mL. No statistically significant difference in diagnostic accuracy was found between point-of-care BNP and NTproBNP tests.

CONCLUSIONS

Given the lack of studies in primary care, the paucity of NTproBNP data, and potential methodological limitations in these studies, large scale trials in primary care are needed to assess the role of point-of-care natriuretic peptide testing and clarify appropriate thresholds to improve care of patients with suspected or chronic heart failure.

Opportunistic screening for heart failure with natriuretic peptides in patients with atrial fibrillation: a meta-analysis of individual participant data of four screening studies

Objective

Heart failure (HF) often coexists in atrial fibrillation (AF) but is frequently unrecognised due to overlapping symptomatology. Furthermore, AF can cause elevated natriuretic peptide levels, impairing its diagnostic value for HF detection. We aimed to assess the prevalence of previously unknown HF in community-dwelling patients with AF, and to determine the diagnostic value of the amino-terminal pro B-type natriuretic peptide (NTproBNP) for HF screening in patients with AF.

Methods

Individual participant data from four HF-screening studies in older community-dwelling persons were combined. Presence or absence of HF was in each study established by an expert panel following the criteria of the European Society of Cardiology. We performed a two-stage patient-level meta-analysis to calculate traditional diagnostic indices.

Results

Of the 1941 individuals included in the four studies, 196 (10.1%) had AF at baseline. HF was uncovered in 83 (43%) of these 196 patients with AF, versus 381 (19.7%) in those without AF at baseline. Median NTproBNP levels of patients with AF with and without HF were 744 pg/mL and 211 pg/mL, respectively. At the cut-point of 125 pg/mL, sensitivity was 93%, specificity 35%, and positive and negative predictive values 51% and 86%, respectively. Only 23% of all patients with AF had an NTproBNP level below the 125 pg/mL cut-point, with still a 13% prevalence of HF in this group.

Conclusions

With a prevalence of nearly 50%, unrecognised HF is common among community-dwelling patients with AF. Given the high prior change, natriuretic peptides are diagnostically not helpful, and straightforward echocardiography seems to be the preferred strategy for HF screening in patients with AF.

MICE or NICE? An economic evaluation of clinical decision rules in the diagnosis of heart failure in primary care

BACKGROUND

Detection and treatment of heart failure (HF) can improve quality of life and reduce premature mortality. However, symptoms such as breathlessness are common in primary care, have a variety of causes and not all patients require cardiac imaging. In systems where healthcare resources are limited, ensuring those patients who are likely to have HF undergo appropriate and timely investigation is vital.

DESIGN

A decision tree was developed to assess the cost-effectiveness of using the MICE (Male, Infarction, Crepitations, Edema) decision rule compared to other diagnostic strategies to identify HF patients presenting to primary care.

METHODS

Data from REFER (REFer for EchocaRdiogram), a HF diagnostic accuracy study, was used to determine which patients received the correct diagnosis decision. The model adopted a UK National Health Service (NHS) perspective.

RESULTS

The current recommended National Institute for Health and Care Excellence (NICE) guidelines for identifying patients with HF was the most cost-effective option with a cost of £4400 per quality adjusted life year (QALY) gained compared to a "do nothing" strategy. That is, patients presenting with symptoms suggestive of HF should be referred straight for echocardiography if they had a history of myocardial infarction or if their NT-proBNP level was ≥400pg/ml. The MICE rule was more expensive and less effective than the other comparators. Base-case results were robust to sensitivity analyses.

CONCLUSIONS

This represents the first cost-utility analysis comparing HF diagnostic strategies for symptomatic patients. Current guidelines in England were the most cost-effective option for identifying patients for confirmatory HF diagnosis. The low number of HF with Reduced Ejection Fraction patients (12%) in the REFER patient population limited the benefits of early detection.