The incremental prognostic and clinical value of multiple novel biomarkers in heart failure

AIMS

In recent years there has been an increase in the number of biomarkers in heart failure (HF). The clinical role for these novel biomarkers in combination is not clear.

METHODS AND RESULTS

The following novel biomarkers were measured from 628 patients recently hospitalized with decompensated HF; mid-regional pro-adrenomedullin (MR-proADM), mid-regional pro-atrial natriuretic peptide (MR-proANP), copeptin, high-sensitivity cardiac troponin T (hs-cTnT), ST2, galectin-3, cystatin C, combined free light chains (cFLC) and high sensitivity C-reactive protein (hsCRP). The incremental prognostic value of these novel biomarkers was evaluated within an extensive model containing established predictors of mortality. During a mean (SD) follow-up of 3.2 (1.5) years, 290 (46%) patients died. Elevated concentrations of all novel biomarkers were associated with an increased unadjusted risk of mortality but only two-thirds were independent predictors following multivariable analysis. Using dichotomized cut-points from receiver operating characteristic analysis, MR-proADM, hs-cTnT, cFLC, hsCRP, and ST2 remained independent predictors of mortality. Further dichotomization into low (0-2 elevated biomarkers) or high (at least three of the five biomarkers elevated) risk groups provided greatest incremental prognostic value (hazard ratio 2.20, 95% confidence interval 1.37-3.54; P = 0.001) and improved the performance of the model (C-statistic 0.730 from 0.721, net reclassification index 32.5%).

CONCLUSION

The novel biomarkers included in this study added little, if any, incremental prognostic value on their own to a model containing established predictors of mortality. However, following dichotomization, five of the novel biomarkers provided incremental prognostic value. There was a clear gradient in the risk of death with increasing numbers of elevated novel biomarkers, with the presence of at least three identifying patients at greatest risk of mortality.

When to consider an implantable cardioverter defibrillator following myocardial infarction?

After reading this article the reader should be familiar with: Current guidelines for implantable cardioverter defibrillator (ICD) use post myocardial infarction (MI) and ischaemic cardiomyopathy. Primary prevention ICD guidelines. Secondary prevention ICD guidelines. Non-sustained ventricular tachycardia in patients post MI and the use of ICDs. Programming ICDs.

The management of patients with aortic regurgitation and severe left ventricular dysfunction: a systematic review

A systematic search of Medline, EMBASE and CINAHL electronic databases was performed. Original research articles reporting all-cause mortality following surgery in patients with aortic regurgitation and severe left ventricular systolic dysfunction (LVSD) were identified. Nine of the 10 eligible studies were observational, single-center, retrospective analyses. Survival ranged from 86 to 100% at 30 days; 81 to 100% at 1 year and 68 to 84% at 5 years. Three studies described an improvement in mean left ventricular ejection fraction (LVEF) following aortic valve replacement (AVR) of 5-14%; a fourth study reported an increase in mean left ventricular ejection fraction (LVEF) of 9% in patients undergoing isolated AVR but not when AVR was combined with coronary artery bypass graft and/or mitral valve surgery. Three studies demonstrated improvements in functional New York Heart Association (NYHA) class following AVR. Additional studies are needed to clarify the benefits of AVR in patients with more extreme degrees of left ventricular systolic dysfunction (LVSD) and the potential roles of cardiac transplantation and transaortic valve implantation.

The ease of use and reproducibility of the Alere™ Heart Check System: a comparison of patient and healthcare professional measurement of BNP

AIMS

The aim of the study was to examine the ease of use and the reproducibility of a novel point-of-care BNP measurement system when used by patients and healthcare providers (HCP).

PATIENTS & METHODS

Patients with symptomatic heart failure were recruited from outpatient clinics at four hospitals. They were provided with brief training and instructional material for the use of the point-of-care BNP measurement system. Finger-prick blood BNP concentration was measured by the HCP and the patient (n = 150). Ease of use and reproducibility of the system were assessed.

RESULTS

In total, 80% of the 164 patients who completed a questionnaire on the ease of use of the system found it easy to operate. There was excellent correlation of BNP measurement compared between patients and HCP (r = 0.966; p < 0.001).

CONCLUSION

Patients find the Alere Heart Check BNP measurement system easy to operate. BNP concentration measurements obtained by patients show excellent correlation with those obtained by healthcare providers.

Biomarkers of acute rejection following cardiac transplantation

Cardiac transplantation can be a life-saving treatment for selected patients with heart failure. However, despite advances in immunosuppressive therapy, acute allograft rejection remains a significant cause of morbidity and mortality. The current 'gold standard' for rejection surveillance is endomyocardial biopsy, which aims to identify episodes of rejection prior to development of clinical manifestations. This is an invasive technique with a risk of false-positive and false-negative results. Consequently, a wide variety of noninvasive alternatives have been investigated for their potential role as biomarkers of rejection. This article reviews the evidence behind proposed alternatives such as imaging techniques, electrophysiological parameters and peripheral blood markers, and highlights the potential future role for biomarkers in cardiac transplantation as an adjunct to biopsy.

Clinical Characteristics and Outcomes of Patients With Coronary Artery Disease and Angina

Background—

The aim of our study was to investigate the relationship between coronary artery disease (CAD), angina, and clinical outcomes in patients with heart failure and preserved ejection fraction enrolled in the irbesartan in patients with heart failure and preserved systolic function (I-Preserve) trial.

Methods and Results—

The mean follow-up period for the 4128 patients enrolled in I-Preserve was 49.5 months. Patients were divided into 4 mutually exclusive groups according to history of CAD and angina: patients with no history of CAD or angina (n=2008), patients with no history of CAD but a history of angina (n=649), patients with a history of CAD but no angina (n=468), and patients with a history of CAD and angina (n=1003); patients with no known CAD or angina were the reference group. After adjustment for other prognostic variables using Cox proportional-hazard models, patients with CAD but no angina were found to be at higher risk of all-cause mortality (hazard ratio [HR], 1.58 [1.22–2.04]; P <0.01) and sudden death (HR, 2.12 [1.33–3.39]; P <0.01), compared with patients with no CAD or angina. Patients with CAD and angina were also at higher risk of all-cause mortality (HR, 1.29 [1.05–1.59]; P =0.02) and sudden death (HR, 1.83 [1.24–2.69]; P <0.01) compared with the same reference group and had the highest risk of unstable angina or myocardial infarction (HR, 5.84 [3.43–9.95]; P <0.01).

Conclusions—

Patients with heart failure and preserved ejection fraction and CAD are at higher risk of all-cause mortality and sudden death when compared with those without CAD.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT00095238.

ICDs in end-stage heart failure

Implantable cardioverter defibrillators (ICDs) reduce mortality in selected patients with chronic heart failure but prognostic benefit is likely to attenuate with progression to end-stage heart failure. The incidence of multiple futile ICD shocks before death is uncertain. Only individual patients, supported by their healthcare professionals, can decide when ICD therapy becomes futile in end-stage heart failure. Despite consensus that ICD deactivation should be routinely discussed, this rarely occurs in clinical practice for many reasons including uncertainty about when to initiate these discussions and reluctance to confront death and dying. Patient and carer opinions about end-stage heart failure and ICD deactivation may not meet professional expectations. Future research should focus on these opinions and examine interventions that bridge the gap between best practice and the reality of current clinical practice.

Palliative care needs in patients hospitalized with heart failure (PCHF) study: rationale and design

Aims

The primary aim of this study is to provide data to inform the design of a randomized controlled clinical trial (RCT) of a palliative care (PC) intervention in heart failure (HF). We will identify an appropriate study population with a high prevalence of PC needs defined using quantifiable measures. We will also identify which components a specific and targeted PC intervention in HF should include and attempt to define the most relevant trial outcomes.

Methods

An unselected, prospective, near‐consecutive, cohort of patients admitted to hospital with acute decompensated HF will be enrolled over a 2‐year period. All potential participants will be screened using B‐type natriuretic peptide and echocardiography, and all those enrolled will be extensively characterized in terms of their HF status, comorbidity, and PC needs. Quantitative assessment of PC needs will include evaluation of general and disease‐specific quality of life, mood, symptom burden, caregiver burden, and end of life care. Inpatient assessments will be performed and after discharge outpatient assessments will be carried out every 4 months for up to 2.5 years. Participants will be followed up for a minimum of 1 year for hospital admissions, and place and cause of death. Methods for identifying patients with HF with PC needs will be evaluated, and estimates of healthcare utilisation performed.

Conclusion

By assessing the prevalence of these needs, describing how these needs change over time, and evaluating how best PC needs can be identified, we will provide the foundation for designing an RCT of a PC intervention in HF.

The Emerging Potential of the Apelin-APJ System in Heart Failure

The apelin-APJ system is a novel neurohormonal pathway, with studies to date suggesting that it may be of pathophysiologic relevance in heart failure and may indeed be a viable therapeutic target in this syndrome. This interest is driven primarily by the demonstration of its vasodilator, inotropic, and aquaretic actions as well as its apparent antagonistic relationship with the renin-angiotensin system. However, its promise is heightened further by the observation that, unlike other and more established cardioprotective pathways, it appears to be down-regulated in heart failure, suggesting that augmentation of this axis may have a powerful effect on the heart failure syndrome. We review the literature regarding the apelin-APJ system in heart failure and suggest areas requiring further research.

Interventricular lead separation is critical for NT-proBNP reduction after cardiac resynchronization therapy

AIMS

Effective cardiac resynchronization therapy may depend upon the distance between left ventricular (LV) and right ventricular (RV) pacing leads. We assessed the influence of lead separation upon circulating NT-proBNP.

MATERIALS & METHODS

In total, 132 patients underwent assessment, including NT-proBNP assay, before and after cardiac resynchronization therapy. 3D lead separation was calculated from postero-anterior and lateral chest radiography.

RESULTS

Lead separation correlated with NT-proBNP reduction (r = 0.25; p = 0.004). Circulating NT-proBNP only fell in those with lead separation in the upper two quartiles. Deteriorating NT-proBNP occurred in 44 patients. Lead separation was less in these patients compared with those with an improvement (corrected 3D lead separation: 148.0 ± 5.38 and 170.5 ± 4.21 mm, respectively; p = 0.0018).

CONCLUSION

Left ventricular-right ventricular lead separation correlates with postcardiac resynchronization therapy improvements in circulating NT-proBNP, a powerful marker of heart failure status and prognosis. Attention should be paid to achieving maximal lead separation at implantation.

Biomarkers in mechanical circulatory support

Heart failure is a complex multifaceted syndrome occurring as a result of impaired cardiac function. Understanding the neurohormonal, inflammatory and molecular pathways involved in the pathophysiology of this syndrome has led to the development of effective and widely used pharmacological treatments. Despite this, mortality and hospitalization rates associated with this condition remain high. The natural course of this illness is usually progressive, often leading inexorably to end stage heart failure, for which orthotopic heart transplant is a treatment option but one with limited resource. In the past decade, mechanical circulatory support has emerged as a potential therapy for certain patients with advanced heart failure. This article reviews the published data regarding biomarkers in the setting of mechanical circulatory support, and highlights areas of ongoing work and potential future areas of interest.

Do plasma concentrations of apelin predict prognosis in patients with advanced heart failure?

Aim: Apelin is an endogenous vasodilator and inotrope, plasma concentrations of which are reduced in advanced heart failure (HF). We determined the prognostic significance of plasma concentrations of apelin in advanced HF. Patients & methods: Plasma concentrations of apelin were measured in 182 patients with advanced HF secondary to left ventricular systolic dysfunction. The predictive value of apelin for the primary end point of all-cause mortality was assessed over a median follow-up period of 544 (IQR: 196–923) days. Results: In total, 30 patients (17%) reached the primary end point. Of those patients with a plasma apelin concentration above the median, 14 (16%) reached the primary end point compared with 16 (17%) of those with plasma apelin levels below the median (p = NS). NT-proBNP was the most powerful prognostic marker in this population (log rank statistic: 10.37; p = 0.001). Conclusion: Plasma apelin concentrations do not predict medium to long-term prognosis in patients with advanced HF secondary to left ventricular systolic dysfunction.

Emerging biomarkers for heart failure: an update

A growing array of biological pathways underpins the syndrome we recognize as heart failure. These include both deleterious pathways promoting its development and progression, as well as compensatory cardioprotective pathways. Components of these pathways can be utilized as biomarkers of this condition to aid diagnosis, prognostication and potentially guide management. As our understanding of the pathophysiology of heart failure deepens further candidate biomarkers are being identified. We provide an overview of the more recently emerging biomarkers displaying potential promise for future clinical use.

Heart failure in younger patients: the Meta-analysis Global Group in Chronic Heart Failure (MAGGIC)

AIM

Our understanding of heart failure in younger patients is limited. The Meta-analysis Global Group in Chronic Heart Failure (MAGGIC) database, which consisted of 24 prospective observational studies and 7 randomized trials, was used to investigate the clinical characteristics, treatment, and outcomes of younger patients.

METHODS AND RESULTS

Patients were stratified into six age categories: <40 (n = 876), 40-49 (n = 2638), 50-59 (n = 6894), 60-69 (n = 12 071), 70-79 (n = 13 368), and ≥80 years (n = 6079). Of 41 926 patients, 2.1, 8.4, and 24.8% were younger than 40, 50, and 60 years of age, respectively. Comparing young (<40 years) against elderly (≥80 years), younger patients were more likely to be male (71 vs. 48%) and have idiopathic cardiomyopathy (63 vs. 7%). Younger patients reported better New York Heart Association functional class despite more severe left ventricular dysfunction (median ejection fraction: 31 vs. 42%, all P < 0.0001). Comorbidities such as hypertension, myocardial infarction, and atrial fibrillation were much less common in the young. Younger patients received more disease-modifying pharmacological therapy than their older counterparts. Across the younger age groups (<40, 40-49, and 50-59 years), mortality rates were low: 1 year 6.7, 6.6, and 7.5%, respectively; 2 year 11.7, 11.5, 13.0%; and 3 years 16.5, 16.2, 18.2%. Furthermore, 1-, 2-, and 3-year mortality rates increased sharply beyond 60 years and were greatest in the elderly (≥80 years): 28.2, 44.5, and 57.2%, respectively.

CONCLUSION

Younger patients with heart failure have different clinical characteristics including different aetiologies, more severe left ventricular dysfunction, and less severe symptoms. Three-year mortality rates are lower for all age groups under 60 years compared with older patients.

The prognostic value of anemia, right-heart catheterization and neurohormones in chronic heart failure

Chronic heart failure is increasing in incidence and prevalence. Recent advances in medical therapy have improved prognosis such that, even in patients with chronic heart failure who are New York Heart Association Classes III and IV, annual mortality can be as low as 11.4%. Nevertheless, some patients remain at risk, despite optimal disease-modifying medical therapy, and it would seem appropriate that these patients are considered first for appropriate device therapy or for the scarce resource of cardiac transplantation. Many parameters have been assessed for their prognostic potential in patients with chronic heart failure. In this review, pertinent studies investigating anemia, right-heart hemodynamics and neurohormones as prognostic markers are discussed.

Deactivation of implantable cardioverter-defibrillators at end of life

It is inevitable that all patients with implantable cardioverter-defibrillators (ICDs) will die during extended follow-up. End-of-life care planning may become appropriate as a patient's condition deteriorates. There is concern about multiple futile shocks in the final hours of life, although the incidence of this problem has been estimated at only 8-16%. Despite broad consensus that ICD deactivation should be discussed as part of end-of-life care planning, the effect of ICD deactivation, in particular whether life expectancy is altered, is uncertain. Many clinicians are reluctant to discuss ICD deactivation. Many patients have misconceptions regarding ICD function and value longevity above quality of life. As such, ICD deactivation is often discussed late or not at all. The management of ICDs in patients approaching death is likely to become a major problem in the coming years. This article will discuss directions in which clinical practice might develop and areas for future research.

Spectral microvolt T-wave alternans testing has no prognostic value in patients recently hospitalized with decompensated heart failure

AIMS

Microvolt T-wave alternans (MTWA) testing identifies beat-to-beat fluctuations in T-wave morphology, which have been linked to ventricular arrhythmias. However, clinical studies have produced conflicting results and data in heart failure (HF) have been limited. The aim of this study was to determine the prevalence and incremental prognostic value of spectral MTWA testing in an unselected cohort of patients recently hospitalized with HF.

METHODS AND RESULTS

Consecutive admissions with confirmed HF were recruited, and survivors were invited to attend 1 month post-discharge for MTWA testing. A total of 648 of 1003 enrolled patients returned for MTWA testing (58% male, mean age 71 years). Forty-nine per cent were ineligible due to AF, pacemaker dependency, or inability to exercise. Of the 330 MTWA test results, 30% were positive, 24% negative, and 46% indeterminate. Overall, 268 deaths occurred during a median follow-up of 3.1 (interquartile range 1.9-3.9) years. Of the ineligible patients, 48% died vs. 35% of eligible patients (P < 0.001). Of those patients with positive, negative, and indeterminate tests, 27, 35, and 40%, respectively, died (P = 0.12). Even when analysed as non-negative (positive/indeterminate) vs. negative, there was still no between-group difference in mortality (P = 0.95). MTWA results categorized as positive, negative, or indeterminate showed no incremental prognostic value in a multivariable model, which included BNP. Paradoxically, when compared in a binary fashion with a non-negative result, a negative test was an independent predictor of death, as was ineligibility for MTWA testing.

CONCLUSION

Spectral MTWA testing was not widely applicable and failed to predict mortality, and so cannot be endorsed as a risk stratification tool in HF.

Use of implantable cardioverter defibrillators in patients with left ventricular assist devices

Patients with left ventricular assist devices (LVADs) are at high risk of sustained ventricular arrhythmias, but these may be remarkably well tolerated and the association with sudden death is unclear. Many patients who receive an LVAD already have an implantable cardioverter defibrillator (ICD). While it is standard practice to reactivate a previously implanted ICD in an LVAD recipient, this should include discussion of the revised risks and benefits of ICD therapy following LVAD implantation. In particular, patients should be warned that they might receive a significant number of ICD shocks that may not be life saving. When ICDs are reactivated, device programming should minimize the risk of repeated shocks for non-sustained or well-tolerated ventricular arrhythmias. Implantation of a primary prevention ICD after implantation of an LVAD is not supported by current evidence, poses potential risks, and should be the subject of a clinical trial before it becomes standard practice.

UK guidelines for referral and assessment of adults for heart transplantation

Patients with advanced heart failure have a dismal prognosis and poor quality of life. Heart transplantation provides an effective treatment for a subset of these patients. This article provides cardiologists with up-to-date information about referral for transplantation, the role of left ventricular assist devices prior to transplant, patient selection, waiting-list management and donor heart availability. Timing is of central importance; patients should be referred before complications (eg, cardiorenal syndrome or secondary pulmonary hypertension) have developed that will increase the risk of, or potentially contraindicate, transplantation. Issues related to heart failure aetiology, comorbidity and adherence to medical treatment are reviewed. Finally, the positive role that cardiologists can play in promoting and facilitating organ donation is discussed.

Novel biomarkers in heart failure: an overview

Heart failure is a complex systemic syndrome resulting from significant impairment of cardiac function. A vast array of biological pathways is now known to be involved in heart failure, including deleterious pathways promoting its development and progression, as well as compensatory cardioprotective pathways. Some of the components of these pathways are now recognized as biomarkers of this condition, and can aid diagnosis, prognostication and guide management. As the understanding of the pathophysiology of heart failure progresses, further candidate biomarkers are being identified. This article reviews the literature regarding the more recently identified biomarkers and outlines areas requiring further study.

Prognostic utility of cardiac troponin in heart failure: a novel role for an established biomarker

Many individual variables are predictive of an increased risk of mortality and morbidity in heart failure. These include a range of data from patient demographics, clinical findings, comorbidities and invasive and noninvasive parameters. Some of these markers, for example the B-type natriuretic peptides, have been identified as independently predictive in large, robust, multivariable analyses. However, many markers have had less vigorous scrutiny and were identified in small cohorts after only univariate or limited multivariable analyses. Recently, cardiac troponins have emerged as potential biomarkers for patients with heart failure. In this article, we consider the utility of cardiac troponins in heart failure and propose what role they may play in improving the risk stratification of this disease.

Can we use B-type natriuretic peptides to monitor patients with heart failure?

The B-type natriuretic peptides (BNPs) now have a well-established role in the diagnosis of heart failure. There is also a wealth of evidence on their ability as prognostic markers in patients with heart failure. The other potential role of BNPs is in the arena of therapy monitoring, although much less is known regarding this putative application. This review summarizes what evidence there is both for and against using BNPs to monitor heart failure patients.

B-type natriuretic peptides in heart failure

There is increasing interest in the B-type natriuretic peptides in many clinical settings, with most research centered on patients with heart failure. These peptides have a strong negative predictive value in patients suspected of having this diagnosis, but are also known to be powerfully predictive of an adverse outcome. This latter property is particularly important in patients with advanced heart failure, allowing the selection of at-risk individuals for therapies that are in scarce resource. There is also ongoing research into B-type natriuretic peptide as a treatment for decompensated heart failure, as well as in other clinical contexts. This review aims to summarize the contemporary and established data on the B-type natriuretic peptides, with particular emphasis in the context of advanced heart failure.

Emerging role of the apelin system in cardiovascular homeostasis

The angiotensin receptor-like 1 (APJ) and its novel ligand, apelin, share similarities in structure and anatomical distribution with that of angiotensin II and the angiotensin II type 1 receptor. However, apelin has positive inotropic, vasodilatory and diuretic properties. Differential expression and synthesis of apelin and the APJ receptor in normal and failing hearts suggest that the apelin system may contribute to the pathophysiology of human heart failure and has potential therapeutic use in treatment of heart failure.

Auto-titrating continuous positive airway pressure therapy in patients with chronic heart failure and obstructive sleep apnoea: a randomized placebo-controlled trial

AIMS

Obstructive sleep apnoea (OSA) is highly prevalent in patients with chronic heart failure (CHF) and may contribute to CHF progression. We aimed to determine whether treatment of OSA with continuous positive airway pressure (CPAP) would improve subjective and objective measures of heart failure severity in patients with CHF and OSA.

METHODS AND RESULTS

Twenty-six patients with stable symptomatic CHF and OSA were randomized to nocturnal auto-titrating CPAP or sham CPAP for 6 weeks each in crossover design. Study co-primary endpoints were changes in peak VO(2) and 6 min walk distance. Secondary endpoints were changes in left ventricular ejection fraction, VE/VCO(2) slope, plasma neurohormonal markers, and quality-of-life measures. Twenty-three patients completed the study protocol. Mean CPAP and sham CPAP usage were 3.5 +/- 2.5 and 3.3 +/- 2.2 h/night, respectively (P = 0.31). CPAP treatment was associated with improvements in daytime sleepiness (Epworth Sleepiness Score 7 +/- 4 vs. 8 +/- 5, P = 0.04) but not in other quality-of-life measures. There were no changes in other study endpoints.

CONCLUSION

In patients with CHF and OSA, auto-titrating CPAP improves daytime sleepiness but not other subjective or objective measures of CHF severity. These data suggest that the potential therapeutic benefits of CPAP in CHF are achieved by alleviation of OSA rather than by improvement in cardiac function.

Informed consent in cardiac surgery: is it truly informed?

OBJECTIVE

To develop a validated questionnaire to measure how informed patients are when giving consent for elective coronary artery bypass grafting.

METHODS

We developed a questionnaire covering the domains described in the consent guidelines published by the General Medical Council. The questionnaire was developed for use in face-to-face interviews as opposed to a self-administered questionnaire. Interviews were conducted after the patients had given consent for surgery. A total of 41 patients were interviewed. To validate the questionnaire we tested the interobserver reliability by using four different interviewers and the construct validity by comparing it with area deprivation index and with predicted intelligence quotient scores obtained from the National Adult Reading Test.

RESULTS

The correlation of the ranking of the questions between the interviewers was satisfactory (Spearman's rank correlation coefficient, rs = 0.84-0.89). The total questionnaire scores correlated well with predicted intelligence quotient scores (rs = 0.48) but not with area deprivation index (rs = 0.01). Questions with the worst scores were those related to mortality, morbidity, alternative treatment options and their relative success rates and risks.

CONCLUSIONS

We have developed a validated questionnaire which tests patient's level of knowledge with respect to surgical myocardial revascularisation. Our study identified areas of informed consent where the minimal level of knowledge is below the recommended level. The questionnaire could be used in audits and clinical trials in patients undergoing coronary artery bypass grafting. It could be used as a tool to measure the effectiveness of patient education programmes. With appropriate changes, this instrument could also be applied in other fields of medical intervention, which require patients to give informed consent.

Plasma concentrations of the novel peptide apelin are decreased in patients with chronic heart failure

BACKGROUND

Apelin, the novel endogenous ligand for the G-protein-coupled receptor APJ, has shown positive inotropic, vasodilatory and diuretic properties in animal studies. Differential expression and synthesis of apelin and APJ receptors have been observed in normal and failing human hearts, suggesting a possible role in cardiovascular homeostasis. Changes in plasma apelin concentrations in relation to heart failure have been described in small studies with conflicting results. Our aim was to evaluate plasma apelin concentrations in a large cohort of patients with chronic heart failure (CHF) across a broad spectrum of disease severity.

METHOD AND RESULTS

Plasma apelin concentrations were measured in 202 patients with CHF secondary to left ventricular systolic dysfunction and 22 age-matched controls. Plasma apelin concentrations were significantly lower in patients with CHF, irrespective of NYHA class, ejection fraction or aetiology when compared to age-matched controls (0.85 [0.53-2.04] versus 3.76 [0.85-5.13] ng/ml, p<0.001). Apelin concentrations were correlated with peak VO(2) and right ventricular ejection fraction, but not with age, sex, body mass index, renal function or NT-proBNP concentrations.

CONCLUSIONS

Plasma apelin concentrations are decreased in patients with CHF. The Apelin-APJ signaling pathway may be a potentially important mediator in the pathophysiological processes of heart failure and may therefore have potential therapeutic implications.

The Modification of Diet in Renal Disease (MDRD) equations provide valid estimations of glomerular filtration rates in patients with advanced heart failure

BACKGROUND

Glomerular filtration rate (GFR) has major prognostic implications in heart failure. Our objective was to validate the MDRD prediction equations for GFR in patients with advanced heart failure, and to compare their predictive performance to that of the Cockcroft-Gault (CG) equation.

METHODS

We analysed GFR in 45 patients referred for heart transplantation evaluation. 51Cr-EDTA-measured GFR was compared to GFR estimates obtained by MDRD1 and MDRD2 equations, CG equation using actual body weight, and ideal body weight. Regression analyses and Pearson correlations were performed, and Bland and Altman plots were drawn. ROC curves were obtained to illustrate each equation's ability to predict a GFR less than 60 ml/min/1.73 m2 (moderate renal impairment).

RESULTS

Patients had a mean age of 52 years, and 69% were in NYHA class III. The mean EDTA-measured GFR was 46.9+/-17.2 ml/min/1.73 m2. The MDRD1 equation provided the best predictive model (narrowest limits of agreement; r = 0.766, p < 0.001), and the highest performance in predicting a GFR less than 60 ml/min/1.73 m2 (area under curve: 0.901).

CONCLUSIONS

MDRD equations, especially MDRD1, adequately predict GFR in advanced heart failure, with higher accuracy than the CG equation. MDRD1 also has higher performance in predicting a GFR less than 60 ml/min/1.73 m2.

N-terminal brain natriuretic peptide is a more powerful predictor of mortality than endothelin-1, adrenomedullin and tumour necrosis factor-alpha in patients referred for consideration of cardiac transplantation

BACKGROUND

The selection of patients for cardiac transplantation is notoriously difficult. We have demonstrated that N-terminal brain natriuretic peptide (NT-proBNP) is a powerful predictor of mortality in advanced heart failure and is superior to the traditional markers of chronic heart failure (CHF) severity. However, the comparative prognostic power of endothelin-1 (Et-1), adrenomedullin (Adm) and tumour necrosis factor-alpha (TNF-alpha) in this patient group is unknown.

METHODS AND RESULTS

We prospectively studied 150 consecutive patients with advanced CHF referred for consideration of cardiac transplantation. Blood samples for NT-proBNP, Et-1, Adm and TNF-alpha analysis were taken at recruitment and patients followed up for a median of 666 days. The primary endpoint of all-cause mortality was reached in 25 patients and the secondary endpoint of all-cause mortality or urgent cardiac transplantation in 29 patients. The median values for NT-proBNP, Et-1, Adm and TNF-alpha were 1494 pg/ml [interquartile range 530-3930], 0.39 fmol/ml [0.10-1.24], 94 pg/ml [54-207] and 2.0 pg/ml [0-18.5] respectively. The only univariate and multivariate predictor of all-cause mortality (chi(2)=26.95, p<0.0001), or the secondary endpoint of all-cause mortality or urgent transplantation (chi(2)=31.23, p<0.0001), was an NT-proBNP concentration above the median value.

CONCLUSION

A single measurement of NT-proBNP in patients with advanced CHF can help identify patients at the highest risk of death, and is a better prognostic marker than Et-1, Adm and TNF-alpha.

N-Terminal Brain Natriuretic Peptide, But Not Anemia, Is a Powerful Predictor of Mortality in Advanced Heart Failure

BACKGROUND

Anemia is prevalent in patients with chronic heart failure, the proportion of which increases with deteriorating New York Heart Association functional class. Anemia is also associated with increased symptoms, more frequent hospitalizations, and, in some studies, with an increased mortality rate. We have demonstrated that N-terminal brain natriuretic peptide (NT-proBNP) is a powerful predictor of death in advanced heart failure and is superior to the traditional markers of chronic heart failure (CHF) severity. However, to date, there are no published data that compare the prognostic ability of NT-proBNP with that of hemoglobin and hematocrit in patients with advanced heart failure who are referred for consideration of cardiac transplantation at a time when erythropoietin is under investigation as a treatment option in such a population.

METHODS AND RESULTS

We prospectively studied 182 consecutive patients with advanced CHF who had been referred for consideration of cardiac transplantation. Blood samples were taken at recruitment for routine investigation and for NT-proBNP analysis; the patients' condition was followed for a median of 554 days. The primary end point of all-cause death was reached in 30 patients, and the secondary end point of all-cause death or urgent cardiac transplantation was reached in 34 patients. The mean hemoglobin level was 13.9 +/- 2.2 g/dL, and the median concentration of NT-proBNP was 1505 pg/mL (interquartile range, 517-4015). The only multivariate predictor of all-cause death (chi 2 = 14.2; P < .001) or the secondary end point of all-cause death or urgent transplantation (chi 2 = 21.8; P < .001) was an NT-proBNP concentration above the median value.

CONCLUSION

A single measurement of NT-proBNP in patients with advanced CHF can help to identify patients who are at a higher risk of death and is a better prognostic marker than anemia.

The prognostic use of right heart catheterization data in patients with advanced heart failure: How relevant are invasive procedures in the risk stratification of advanced heart failure in the era of neurohormones?

BACKGROUND

Right heart catheterization long has been a routine investigation in advanced heart failure, and its measurements have been linked variably to prognosis. However, in the modern era, newer potential markers of prognosis are coming to light. This study reconsiders the use of right heart catheterization data and compares their use to that of N-terminal pro-brain natriuretic peptide (NT-proBNP), a neurohormone linked with prognosis in chronic heart failure.

METHODS

We assessed prospectively the prognostic potential of baseline right heart catheterization data in 97 consecutive patients with advanced heart failure referred to the Scottish Cardiopulmonary Transplant Unit for consideration of cardiac transplantation. Patients underwent baseline routine investigation, including right heart catheterization and blood draws for NT-proBNP analysis. Patients were observed for a median of 370 days.

RESULTS

The primary end-point of all-cause mortality was reached in 17 patients (17.5%), and the secondary end-point of all-cause mortality or urgent cardiac transplantation was reached in 21 (21.6%) patients. Univariate predictors of all-cause mortality included pulmonary artery systolic pressure (PASP), pulmonary artery wedge pressure (PAWP), and NT-proBNP concentration greater than their median values. Univariate predictors of the secondary end-point included right atrial pressure, PASP, PAWP, and NT-proBNP concentration greater than their median values, and left ventricular ejection fraction, cardiac output, and cardiac index less than their median values. In multivariate analyses, however, only NT-proBNP concentration remained an independent predictor of all-cause mortality. Both NT-proBNP concentration and PAWP were independent predictors of all-cause mortality and of the need for urgent cardiac transplantation.

CONCLUSION

Baseline data from routine right heart catheterization are of limited prognostic use in advanced heart failure. A baseline NT-proBNP concentration is a superior, non-invasive method of risk stratification in this era of measuring neurohormones.