Prognostic Factors in Chronic Heart Failure: A Review of Serum Biomarkers, Metabolic Changes, Symptoms, and Scoring Systems

Vasodilation and Exercise Capacity in Patients with End-Stage Renal Disease: A Prospective Proof-of-Concept Study

BACKGROUND

Previous data have pointed to the fact that vascular function is significantly impaired in patients with end-stage renal disease (ESRD). We aimed to better characterise vasodilation and exercise capacity in both ESRD and chronic heart failure (CHF) patients.

METHODS

A total of 30 ESRD patients (23 male; mean age 45.7 ± 9.9 years) were included in a prospective proof-of-concept study at a tertiary care academic centre. The patients underwent forearm venous plethysmography with post-ischaemic peak blood flow (PF) and flow-dependent flow (FDF) testing as well as cardiopulmonary exercise testing during the morning of the day following the last haemodialysis. After matching for age, gender, and body mass index, the data were compared to 30 patients with CHF and 20 age-matched healthy controls.

RESULTS

PF in ESRD patients was reduced when compared to that in CHF patients (12.5 ± 4.2 vs. 15.6 ± 6.9 ml/100 ml/min; p = 0.048) and healthy controls (26.4 ± 9.3 ml/100 ml/min; p < 0.001). When compared to controls, FDF was significantly reduced in ESRD patients (7.6 ± 3.1 vs. 6.0 ± 2.5 ml/100 ml/min; p = 0.03), but not in CHF patients, whereas resting blood flow did not differ between the ESRD, CHF, and healthy control groups. In contrast to indices of vasodilative capacity, maximum exercise capacity (peakVO₂) was higher in ESRD when compared to CHF patients (23.8 ± 7.3 vs. 18.8 ± 5.2 ml/min/kg), but significantly impaired when compared to controls (32.8 ± 6.7 ml/min/kg; p < 0.001).

CONCLUSION

In this proof-of-concept study, exercise capacity was relatively preserved, while vasodilative capacity was substantially impaired in ESRD patients. Additional studies are warranted to examine the underlying mechanisms and potential clinical implications of our findings.

Multiplexing and Beyond in Biobehavioral Research

In contrast to traditional singleplex assays that provide values for only a single analyte in a single biological sample, multiplex assays are a time- and resource-efficient high-throughput approach that provides the opportunity to determine numerous analytes within a single- and small-sample volume. In this editorial on an article by Dorn et al. in this issue of Psychosomatic Medicine, we provide a brief description of the advantages and challenges related to multiplex assays. Although the use of multiplexing as a tool has been relatively limited in biobehavioral research, more recent studies are taking advantage of this technology to obtain deeper insight into regulatory patterns in health and disease states. Multiplex approaches range from several targets to global target profiling that importantly enable unbiased biomarker and pathway discovery.

A pilot study of angiogenin in heart failure with preserved ejection fraction: a novel potential biomarker for diagnosis and prognosis?

Characteristics of heart failure with preserved ejection fraction (HFPEF) have not yet been fully understood. The objectives of this pilot study are to detect protein expression profile in the sera of HFPEF patients, and to identify potential biomarkers for the disease. Five hundred and seven proteins were detected in the sera of healthy volunteers and patients with either HFPEF or hypertension using antibody microarrays (three in each group). The results showed that the serum concentrations of 17 proteins (e.g. angiogenin, activin A and artemin) differed considerably between HFPEF and non-HFPEF patients (hypertensive patients and healthy controls), while a protein expression pattern distinct from that in non-HFPEF patients was associated with HFPEF patients. The up-regulation of angiogenin in both HFPEF patients with LVEF ≥50% (P = 0.004) and a subset of HFPEF patients with LVEF = 41–49% (P < 0.001) was further validated in 16 HFPEF patients and 16 healthy controls. Meanwhile, angiogenin distinguished HFPEF patients from controls with a mean area under the receiver operating characteristic curve of 0.88 (P < 0.001) and a diagnostic cut-off point of 426 ng/ml. Moreover, the angiogenin levels in HFPEF patients were positively correlated with Lg(N-terminal pro-B-type natriuretic peptide, NT-proBNP) (P < 0.001). In addition, high angiogenin level (≥426 ng/ml) was a predictor of all-cause death within a short-term follow-up duration, but not in the longer term of 36 months. This pilot study indicates that the aforementioned 17 potential biomarkers, such as angiogenin, may hold great promise for both diagnosis and prognosis assessment of HFPEF.

Outcomes of children following a first hospitalization for dilated cardiomyopathy

BACKGROUND

We hypothesized that children with dilated cardiomyopathy who require hospital admission are at increased risk for death or transplantation during their first hospitalization and in the first year that follows. We also assessed the value of routine data collected during that time to predict death or the need for transplantation prior to discharge and within 1 year of admission.

METHODS AND RESULTS

We conducted a retrospective review of 83 pediatric patients with dilated cardiomyopathy whose initial hospitalization fell between 2004 and 2009. The mean age at hospitalization was 7 years. The majority of patients demonstrated moderate or severe left ventricular dysfunction on initial echocardiogram (80%) and/or the need for intravenous inotropes within 7 days of hospital admission (69%). Five patients (6%) died, and 15 (18%) were transplanted in the initial hospitalization. At 1 year, 11/71 (15%) had died, and 27/71 (38%) were transplanted. The overall freedom from death, transplantation, or rehospitalization at 1 year following admission was 21%. Fractional shortening, left ventricular ejection fraction, serum cholesterol, uric acid, mixed venous saturation, and atrial filling pressures were all predictive of death or transplantation during the initial hospitalization. Left ventricular ejection fraction was predictive of death or transplantation at 1 year.

CONCLUSIONS

The first hospitalization for dilated cardiomyopathy marks a period of high risk for clinical decline, end stage heart failure, and the need for cardiac transplantation. Echocardiographic function and hemodynamic and serum measurements may aid in predicting outcomes. Despite medical management, most patients will be rehospitalized and/or require cardiac transplantation within 1 year of admission.

Who has advanced heart failure?: definition and epidemiology

Summarizing current guidelines and advanced heart failure (AHF) clinical trials/registries, this review focuses on the current definition of AHF and emphasizes the secular trends in this definition over the last two decades. Further, clinical, imaging, hemodynamic, functional capacity and biomarker parameters that may aid clinicians to better recognize patients with AHF are reviewed. Finally, we review the limited data concerning the epidemiology of AHF which to date has been poorly characterized.

[Heart failure update 2010 and current ESC guidelines]

Chronic heart failure may be caused by systolic pump failure and/or impairment of diastolic filling of the ventricles. Standard pharmacotherapy of systolic heart failure includes an ACE inhibitor, betablocker, diuretics and in patients with severe symptoms a low-dose aldosterone antagonist. An AT(1) receptor blocker is indicated in those not tolerating ACE inhibitors. If patients remain in functional class NYHA III-IV despite optimal medication and have cardiac dyssynchrony, biventricular pacing may improve symptoms and prognosis. While evidence-based treatment significantly reduces morbidity and mortality in systolic heart failure, hardly any results of clinical trials are available for diastolic heart failure. Therefore, therapy in patients with diastolic heart failure remains symptomatic in most cases.

[Isolated systolic hypertension. An independent disease]

Hypertension can be classified based on certain criteria, such as severity, existence of specific end-organ damage, or the dominant blood pressure subphenotype so that isolated diastolic hypertension (IDH), mixed systolic-diastolic hypertension (SDH), and isolated systolic hypertensive (ISH) states can be defined. The FRAMINGHAM study was the first to demonstrate a continuous increase of systolic blood pressure with age and a peak of diastolic pressure between 55 and 65 years of age. This results not only in a high prevalence of hypertension of approximately 50-80% beyond the age of 60 but also in a disproportionately high increase in isolated systolic hypertension. ISH develops either as a new condition mostly from the group of primary high-normal blood pressure or secondly through burnout of existing systolic-diastolic hypertension with highly progressive vascular ageing.The pathophysiological background lies in remodeling processes in the macrovascular and microvascular compartments with stiffening of conduit and peripheral arterial vessels. In clinical practice these processes are easy to measure by determining pulse wave velocity (PWV), the augmentation index, and pulse pressure. These parameters are closely related to cardiovascular and cerebrovascular morbidity and mortality ISH is not only a hypertension subphenotype but often indicates significant organ damage or may even be considered to be a secondary form of hypertension characterized by remodeled and stiffened arterial vessel walls and this condition is difficult to treat. It appears therefore that ISH warrants special therapeutic strategies with a focus on antiproliferative, antistiffening, anti-atherosclerotic, and vasodilating actions. As a result of the available data from the results of treatment studies it appears that renin-angiotensin system (RAS) blockers and calcium channel blockers (CCBs) are the preferred drugs for treatment of this condition.

Growth differentiation factor-15: a new biomarker in cardiovascular disease

Growth differentiation factor-(GDF-)15 is a stress-responsive cytokine that is emerging as a biomarker of cardiac and vascular dysfunction and disease. Elevated circulating levels of GDF-15 identify high-risk individuals across the cardiovascular continuum, from stable coronary artery disease to acute coronary syndrome and heart failure. The association of GDF-15 with outcome in these conditions is independent of clinical risk factors and established biomarkers, including NT-proBNP (N-terminal pro-B-type natriuretic peptide) and troponin. The prognostic information provided by GDF-15 in cardiovascular disease may inform patient management, e.g., by identifying patients with non-ST segment elevation acute coronary syndrome who benefit from an invasive strategy, or by monitoring treatment response in heart failure. Future studies need to evaluate prospectively whether GDF-15, alone or as part of a multimarker strategy, can improve contemporary risk prediction algorithms and support therapeutic management of patients with cardiovascular disease.

Biomarkers for chronic heart failure : diagnostic, prognostic, and therapeutic challenges

Cardiac biomarkers are very important in diagnosis, risk stratification, and management of patients with heart failure. Although not meeting all criteria for an ideal biomarker, natriuretic peptides primarily have a diagnostic and prognostic role. Other routinely available and newly emerging biomarkers have a complementary role in patient management; thus multimarker strategy might be warranted in future. The quest for a single marker or a combination is ongoing and several established, widely available biomarkers might have been overlooked in the field of heart failure. The authors review some of those biomarkers and speculate on the possible roles of combining two or more of them.

Heart failure and mouse models

Heart failure is a common, complex condition with a poor prognosis and increasing incidence. The syndrome of heart failure comprises changes in electrophysiology, contraction and energy metabolism. This complexity, and the interaction of the clinical syndrome with very frequently concurrent medical conditions such as diabetes, means that animal modelling of heart failure is difficult. The current animal models of heart failure in common use do not address several important clinical problems. There have been major recent advances in the understanding of cardiac biology in the healthy and failing myocardium, but these are, as yet, unmatched by advances in therapeutics. Arguably, the development of new animal models of heart failure, or at least adaptation of existing models, will be necessary to fully translate scientific advances in this area into new drugs. This review outlines the mouse models of heart failure in common usage today, and discusses how adaptations in these models may allow easier translation of animal experimentation into the clinical arena.

Glutamate synthase: a fascinating pathway from L-glutamine to L-glutamate

Glutamate synthase is a multicomponent iron-sulfur flavoprotein belonging to the class of N-terminal nucleophile amidotransferases. It catalyzes the conversion of L-glutamine and 2-oxoglutarate into two molecules of L-glutamate. In recent years the X-ray structures of the ferredoxin-dependent glutamate synthase and of the a subunit of the NADPH-dependent glutamate synthase have become available. Thanks to X-ray crystallography, it is now known that the ammonia reaction intermediate is transferred via an intramolecular tunnel from the amidotransferase domain to the synthase domain over a distance of about 32A. Although ammonia channeling is a recurrent theme for N-terminal nucleophile and triad-type amidotransferases, the molecular mechanisms of ammonia transfer and its control are different for each known amidotransferase. This review focuses on the intriguing mechanism of action and self-regulation of glutamate synthase with a special focus on the structural data.

Novel estrogen receptor coregulators and signaling molecules in human diseases

The steroid hormone estrogen and signaling from its receptors are increasingly recognized as critical mediators of a variety of organ-specific biological processes. Recent advances in the identification and functional characterization of novel estrogen receptor interacting proteins clearly show the complexity of hormonal signaling regulation, but may also contribute to our understanding of the roles of estrogen signaling in normal physiology and the pathobiology of human disease.