A prospective study in search of an optimal B-natriuretic peptide level to screen patients for cardiac dysfunction

Triple Cascade Quantum-Strip for Heart Failure Point-of-Care Testing

Heart failure (HF) is a life-threatening syndrome. Timely and accurate bedside monitoring of the occurrence and progression of HF via measurements of multiple HF-related biomarkers remains a challenge. Here, we report a triple cascade quantum-strip (TCQS) sensing strategy for the rapid and selective multiplex-tracing of three clinically validated HF biomarkers (BNP/NT-proBNP/ST2) in serum. High selectivity to the three biomarkers is achieved by controlling the individual recognition ability of three target-specific quantum immunoprobes and tuning their simultaneous use to BNP/NT-proBNP/ST2 recognition without mutual interference, which allows the three biomarkers to be directly enriched from serum samples. Benefiting from the fast release-binding kinetics of target-bound immunoprobes on TCQS, recognizable fluorescent signals can be rapidly read out through combining with a self-designed smartphone-based portable reader. This rapid and simple profiling strategy results in good specificity and sensitivity with LODs of 0.097, 0.072, and 0.948 ng/mL for BNP, NT-proBNP, and ST2, respectively, which match the need of clinical applications. Real serum samples are tested with an accuracy of 92.86% for HF diagnosis, validating the capability of the smartphone-read TCQS for practical applications. In particular, the simultaneous detection of the TCQS sensing strategy for BNP/NT-proBNP/ST2 will facilitate the accurate monitoring of HF occurrence, risk stratification, progression, and prognosis as a powerful POCT tool.

Causal relationship between gut microbes and cardiovascular protein expression

Evidence supports associations between gut microbiota and cardiovascular protein levels in plasma. However, it is unclear whether these associations reflect a causal relationship. To reveal the causal relationship between gut microbiota and cardiovascular protein levels in plasma, we estimated their causal effects using two-sample Mendelian randomization (MR) analysis. Sensitivity analysis was also performed to assess the robustness of our results. Genome-wide association study (GWAS) of microbiomes in the MiBioGen study included 211 bacterial taxa (18,473 individuals), and GWAS of 90 cardiovascular proteins included 30,931 individuals. There were 196 bacterial taxa from five levels available for analysis. The following 14 causal relationships were identified: phylum Euryarchaeota and carbohydrate antigen 125 (β = 0.289), order Bacillales and CSF-1 (β = -0.211), genus Dorea and HSP-27 (β = 0.465), phylum Actinobacteria and IL-8 (β = 0.274), order Enterobacteriales and KIM-1 (β = -0.499), class Actinobacteria, genus Bifidobacterium, phylum Actinobacteria and LEP (β = -0.219, β = -0.201, and β = -0.221), genus Methanobrevibacter and NT-proBNP (β = 0.371), family Peptostreptococcaceae and SRC (β = 0.191), order Verrucomicrobiales, phylum Verrucomicrobia and TNF-R2 (β = 0.251 and β = 0.233), family Veillonellaceae and t-PA (β = 0.271), and class Erysipelotrichia and VEGF-D (β = 0.390). Sensitivity analysis showed no evidence of pleiotropy or heterogeneity. The results of the reverse MR analysis showed no reverse causality for any of the 13 gut microbes and 11 cardiovascular proteins. Mendelian randomization estimates provide strong evidence for a causal effect of gut microbiota-mediated alterations on cardiovascular protein expression.

Serum soluble (pro)renin receptor level as a prognostic factor in patients undergoing maintenance hemodialysis

The (pro)renin receptor [(P)RR)] is a multifunctional protein that is cleaved to generate the soluble (P)RR [s(P)RR], reflecting the status of the tissue renin-angiotensin system and/or activity of the (P)RR. The serum s(P)RR level is associated with arteriosclerosis, independent of other risk factors, in patients undergoing hemodialysis (HD). This study was conducted to investigate whether the s(P)RR level was associated with new-onset cardiovascular events or malignant diseases and poor prognosis in patients undergoing HD. Overall, 258 patients [70 (61–76) years, 146 males] undergoing maintenance HD were prospectively followed up for 60 months. We investigated the relationships between s(P)RR levels and new-onset cardiovascular events/ malignant diseases and mortality during the follow-up period using Cox proportional hazard analyses. The cumulative incidence of new-onset cardiovascular events (P = 0.009) and deaths (P < 0.001), but not of malignant diseases, was significantly greater in patients with higher serum s(P)RR level (≥ 29.8 ng/ml) than in those with lower s(P)RR level (< 29.8 ng/ml). A high serum s(P)RR level was independently correlated with cardiovascular mortality (95% CI 1.001–1.083, P = 0.046). The serum s(P)RR level was associated with cardiovascular events and mortality, thus qualifying as a biomarker for identifying patients requiring intensive care.

Blood-Based Biomarkers Are Associated with Different Ischemic Stroke Mechanisms and Enable Rapid Classification between Cardioembolic and Atherosclerosis Etiologies

Stroke is a top leading cause of death, which occurs due to interference in the blood flow of the brain. Ischemic stroke (blockage) accounts for most cases (87%) and is further subtyped into cardioembolic, atherosclerosis, lacunar, other causes, and cryptogenic strokes. The main value of subtyping ischemic stroke patients is for a better therapeutic decision-making process. The current classification methods are complex and time-consuming (hours to days). Specific blood-based biomarker measurements have promising potential to improve ischemic stroke mechanism classification. Over the past decades, the hypothesis that different blood-based biomarkers are associated with different ischemic stroke mechanisms is increasingly investigated. This review presents the recent studies that investigated blood-based biomarker characteristics differentiation between ischemic stroke mechanisms. Different blood-based biomarkers are specifically discussed (b-type natriuretic peptide, d-dimer, c-reactive protein, tumor necrosis factor-α, interleukin-6, interleukin-1β, neutrophil-lymphocyte ratio, total cholesterol, triglycerides, low-density lipoprotein, high-density lipoprotein and apolipoprotein A), as well as the different cut-off values that may be useful in specific classifications for cardioembolic and atherosclerosis etiologies. Lastly, the structure of a point-of-care biosensor device is presented, as a measuring tool on-site. The information presented in this review will hopefully contribute to the major efforts to improve the care for stroke patients.

B-Type Natriuretic Peptide as a Significant Brain Biomarker for Stroke Triaging Using a Bedside Point-of-Care Monitoring Biosensor

Stroke is a widespread condition that causes 7 million deaths globally. Survivors suffer from a range of disabilities that affect their everyday life. It is a complex condition and there is a need to monitor the different signals that are associated with it. Stroke patients need to be rapidly diagnosed in the emergency department in order to allow the admission of the time-limited treatment of tissue plasminogen activator (tPA). Stroke diagnostics show the use of sophisticated technologies; however, they still contain limitations. The hidden information and technological advancements behind the utilization of biomarkers for stroke triaging are significant. Stroke biomarkers can revolutionize the way stroke patients are diagnosed, monitored, and how they recover. Different biomarkers indicate different cascades and exhibit unique expression patterns which are connected to certain pathologies in the human body. Over the past decades, B-type natriuretic peptide (BNP) and its derivative N-terminal fragment (NT-proBNP) have been increasingly investigated and highlighted as significant cardiovascular biomarkers. This work reviews the recent studies that have reported on the usefulness of BNP and NT-proBNP for stroke triaging. Their classification association is also presented, with increased mortality in stroke, correlation with cardioembolic stroke, and an indication of a second stroke recurrence. Moreover, recent scientific efforts conducted for the technological advancement of a bedside point-of-care (POC) device for BNP and NT-proBNP measurements are discussed. The conclusions presented in this review may hopefully assist in the major efforts that are currently being conducted in order to improve the care of stroke patients.

Assessment of ventricular dysfunction in Egyptian children with Beta-thalassemia major

OBJECTIVE/BACKGROUND

The purpose of this study was to evaluate serum cardiac troponin I and serum N-terminal (NT) pro-brain natriuretic peptide (pro-BNP) levels and the utility of tissue Doppler imaging in assessing cardiovascular changes following left ventricular (LV) dysfunction in children with beta-thalassemia major (β-TM). In children with β-TM who depend on regular blood transfusion, cardiac iron toxicity is a common serious complication. The most common cause of death among these patients is congestive heart failure.

METHODS

This is a cross-sectional study which included 50 patients with β-TM and 50 healthy controls. Tissue Doppler imaging was performed and levels of serum ferritin, cardiac troponin I, and NT pro-BNP were estimated for all included patients.

RESULTS

Serum NT pro-BNP and cardiac troponin (cTnI) showed a significant increase in patients with β-TM (p < .001). In patients with β-TM, LV dimensions (LV end systolic diameter) and (LV end diastolic diameter) were large (p < .01); LV mass (p < .01), E wave, and E/A ratio (p < .01) were high (p < .05); and deceleration time was short (p < .05). Besides, transmitral ratio (E/E_m) (p < .05) and tricuspid valve velocity were higher (p < .05), and early diastolic velocity (E_m) (p < .05) and systolic wave velocity (S_m) were lower in patients with β-TM (p < .05). A significant positive correlation was detected between the pro-BNP and E wave (r = 0.558, p < .001), E/A ratio (r = 0.403, p < .001), E/E_m ratio (r = 0.576, p < .001), and ferritin (r = 0.545, p < .001).

CONCLUSION

Pulsed wave tissue Doppler imaging and NT pro-BNP had a significant role in the estimation of ventricular dysfunction in children with β-TM.

Association between serum soluble (pro)renin receptor level and worsening of cardiac function in hemodialysis patients: A prospective observational study

The (pro)renin receptor ((P)RR) is cleaved to generate soluble (P)RR (s(P)RR), which reflects the status of the tissue renin-angiotensin system. Hemodialysis (HD) patients have a poor prognosis due to the increased prevalence of cardiovascular diseases. The present study aimed to investigate whether serum s(P)RR level is associated with the worsening of cardiac function in HD patients. A total of 258 maintenance HD patients were recruited and serum s(P)RR concentration was measured. Background factors in patients who survived (S group) and patients who died (D group) during the 12-month follow-up period and relationships between serum s(P)RR level and changes in cardiac function during the follow-up period in the S group were investigated. The median serum s(P)RR value at baseline was 29.8 ng/ml. Twenty-four patients died during the follow-up period. Cardiothoracic ratio, human atrial natriuretic peptide (hANP), brain natriuretic peptide (BNP), and E over e-prime were significantly higher in the D group. In the S group, changes in hANP or BNP were significantly greater in the higher serum s(P)RR group than in the lower serum s(P)RR group. High serum s(P)RR level was significantly correlated with changes in BNP, independent of other factors. High serum s(P)RR level was associated with increases in BNP, independent of other risk factors, suggesting that an increased expression of (P)RR may be associated with a progression of heart failure in HD patients and that serum s(P)RR concentration could be used as a biomarker for selecting patients requiring intensive care.

Serum levels of carbohydrate antigen 125 in combination with N-terminal pro-brain natriuretic peptide in patients with acute decompensated heart failure

BACKGROUND/AIMS

Carbohydrate antigen 125 (CA-125) is an emerging prognostic biomarker for heart failure. We aimed to test the long-term prognostic value of CA-125 in combination with N-terminal pro-brain natriuretic peptide (NT-proBNP) in patients with acute decompensated heart failure (ADHF).

METHODS

This observational study included a total of 413 patients (64.1 ± 15.6 yearold, 214 men) with ADHF. All-cause mortality during the 2-year follow-up was investigated for the prognosis.

RESULTS

During the follow-up (mean follow-up, 591 ± 233 days), 109 deaths (26.0%) were recorded. In the multivariable analysis model, CA-125 was an independent factor associated with all-cause mortality (log CA-125: hazard ratio, 1.23; 95% confidence interval, 1.02 to 1.48; p = 0.030) together with age, sex, New York Heart Association class, β-blocker, and NT-proBNP. The Kaplan-Meier survival analysis demonstrated that the group with both low marker levels showed the best 2-year survival (87.9%) followed by the group with low NT-proBNP and high CA-125 (76.1%), high NT-proBNP and low CA-125 (64.7%) and high NT-proBNP and high CA-125 levels (54.3%) (p < 0.001). Addition of CA-125 in combination with NT-proBNP and established risk factors further increased the predictive power for mortality in patients with ADHF.

CONCLUSION

CA-125 was an independent factor associated with all-cause mortality in patients with ADHF. Combination of CA-125 with NT-proBNP significantly improved the prediction of mortality in patients with ADHF.

Point-of-Care Surface Plasmon Resonance Biosensor for Stroke Biomarkers NT-proBNP and S100β Using a Functionalized Gold Chip with Specific Antibody

Surface-plasmon-resonance (SPR) is a quantum-electromagnetic phenomenon arising from the interaction of light with free electrons at a metal-dielectric interface. At a specific angle/wavelength of light, the photon's energy is transferred to excite the oscillation of the free electrons on the surface. A change in the refractive-index (RI) may occur, which is influenced by the analyte concentration in the medium in close contact with the metal surface. SPR has been widely used for the detection of gaseous, liquid, or solid samples. In this study, a functionalized specific SPR chip was designed and used in a novel point-of-care SPR module (PhotonicSys SPR H5) for the detection of the stroke biomarkers NT-proBNP and S100β. These biomarkers have proven to be good for stroke diagnosis, with sensitivity and specificity of >85%. Specific detection was done by binding a biomolecular-recognizing antibody onto the Au SPR-chip. Detection was tested in water and plasma samples. NT-proBNP and S100β were detected in a range of concentrations for stroke, from 0.1 ng/mL to 10 ng/mL. The RI of the blank plasma samples was 1.362412, and the lowest concentration tested for both biomarkers showed a prominent shift in the RI signal (0.25 ng/mL NT-proBNP (1.364215) and S100β (1.364024)). The sensor demonstrated a clinically relevant limit-of-detection of less than ng/mL.

Cardiac biomarkers but not measures of vascular atherosclerosis predict mortality in patients with peripheral artery disease

BACKGROUND

Peripheral artery disease (PAD) becomes more prevalent with advancing age and is associated with elevated risk of cardiovascular events and shortened life expectancy. We investigated the prognostic performance of cardiac and vascular biomarkers in a cohort of PAD patients.

METHODS

A total of 95 PAD patients were enrolled (mean age 68 years, range 47 to 86 years, 73 males). Carotid intima-media thickness (cIMT), ankle brachial index (ABI), high sensitive cardiac troponin T, and N-terminal pro-B-type Natriuretic Peptide (NT-proBNP) were measured.

RESULTS

During a median follow-up time of 9.5 years, 44 patients died and 51 patients survived. Upon Kaplan-Meier survival analysis hs-TnT (P < .001) or NT-proBNP levels (P < .001) above the median but not cIMT above the median (P = .488) or ABI below the median (P < .436)were associated with reduced survival rate. Upon univariate cox regression and after adjustment for age, gender, prior cerebral artery disease, and diabetes mellitus only the association between hs-cTnT and mortality remained significant (HR 1.93, 95% CI 1.33-2.79, P < .001). In receiver operating curve analysis hs-cTnT (area under the curve [AUC]: 0.77, 95% CI: 0.67-0.87, P < .001) NT-proBNP (AUC: 0.74, 95% CI: 0.64-0.84, P < .001) as well as hs-cTnT, and NT-proBNP combined (AUC: 0.79, 95% CI: 0.69-0.88, P < .001) were superior to cIMT (AUC: 0.64, 95%, CI: 0.53-0.76, P = .022) and ABI (AUC: 0.57, 95% CI: 0.44-0.68, P = .313) in discriminating risk for mortality.

CONCLUSION

hs-cTnT and NT-proBNP should be taken into account for prognosis of patients with PAD.

Valproic Acid Induces Endothelial-to-Mesenchymal Transition-Like Phenotypic Switching

Valproic acid (VPA), a histone deacetylase (HDAC) inhibitor, is a widely used anticonvulsant drug that is currently undergoing clinical evaluation for anticancer therapy due to its anti-angiogenic potential. Endothelial cells (ECs) can transition into mesenchymal cells and this form of EC plasticity is called endothelial-to-mesenchymal transition (EndMT), which is widely implicated in several pathologies including cancer and organ fibrosis. However, the effect of VPA on EC plasticity and EndMT remains completely unknown. We report herein that VPA-treatment significantly inhibits tube formation, migration, nitric oxide production, proliferation and migration in ECs. A microscopic evaluation revealed, and qPCR, immunofluorescence and immunoblotting data confirmed EndMT-like phenotypic switching as well as an increased expression of pro-fibrotic genes in VPA-treated ECs. Furthermore, our data confirmed important and regulatory role played by TGFβ-signaling in VPA-induced EndMT. Our qPCR array data performed for 84 endothelial genes further supported our findings and demonstrated 28 significantly and differentially regulated genes mainly implicated in angiogenesis, endothelial function, EndMT and fibrosis. We, for the first time report that VPA-treatment associated EndMT contributes to the VPA-associated loss of endothelial function. Our data also suggest that VPA based therapeutics may exacerbate endothelial dysfunction and EndMT-related phenotype in patients undergoing anticonvulsant or anticancer therapy, warranting further investigation.

Point-of-Care-Testing in Acute Stroke Management: An Unmet Need Ripe for Technological Harvest

Stroke, the second highest leading cause of death, is caused by an abrupt interruption of blood to the brain. Supply of blood needs to be promptly restored to salvage brain tissues from irreversible neuronal death. Existing assessment of stroke patients is based largely on detailed clinical evaluation that is complemented by neuroimaging methods. However, emerging data point to the potential use of blood-derived biomarkers in aiding clinical decision-making especially in the diagnosis of ischemic stroke, triaging patients for acute reperfusion therapies, and in informing stroke mechanisms and prognosis. The demand for newer techniques to deliver individualized information on-site for incorporation into a time-sensitive work-flow has become greater. In this review, we examine the roles of a portable and easy to use point-of-care-test (POCT) in shortening the time-to-treatment, classifying stroke subtypes and improving patient's outcome. We first examine the conventional stroke management workflow, then highlight situations where a bedside biomarker assessment might aid clinical decision-making. A novel stroke POCT approach is presented, which combines the use of quantitative and multiplex POCT platforms for the detection of specific stroke biomarkers, as well as data-mining tools to drive analytical processes. Further work is needed in the development of POCTs to fulfill an unmet need in acute stroke management.

Electrochemical impedimetric detection of stroke biomarker NT-proBNP using disposable screen-printed gold electrodes

Stroke is the second top leading cause of death globally. It is caused by an abrupt interruption of blood flow to the brain. In that course, brain natriuretic peptide (BNP) and its derivative N-terminal pro b-type natriuretic peptide (NT-proBNP), neurohormones produced mainly by the heart ventricles in response to excessive stretching of cardiomyocytes (heart muscle cells), are proven to be good biomarkers for heart failure diagnosis. Moreover, there is growing clinical interest of the use of NT-proBNP for stroke diagnosis and prognosis because it is significantly associated with cardioembolic stroke and secondary stroke reoccurrence, with sensitivity >90% and specificity >80%. However, in diagnostic settings, there is still a need to address the encountered analytical problems, particularly assay specificity and set up. In this study, a novel approach for NT-proBNP detection is demonstrated using an electrochemical immunoassay method. A label-free impedimetry immunosensor for stroke biomarker was developed using modified disposable screen-printed gold electrodes (SPGE) hosting specific anti-NT-proBNP capture antibody. The performance of our immunosensor was studied in the presence of NT-proBNP in both buffered and mock (porcine) plasma samples. A linear relation between the relative total resistance (ΔRtot) responses and the NT-proBNP concentrations in buffer was observed in a range from 0.1 to 5 ng mL-1 with a correlation coefficient (R2) of 0.94656. Overall, the biosensor has demonstrated the capability to quantitate NT-proBNP and differentiate such concentrations in a low concentration range, especially among 0, 0.1, 0.5, 1, and 3 ng mL-1 in plasma samples within 25 min. This range is valuable not only for classifying cardioembolic stroke (higher or equal to 0.5 ng mL-1), but also predicting the risk of secondary stroke reoccurrence (higher than 0.255 ng mL-1). Our biosensor has the potential to be used as an easy-to-use point-of-care test that is both accurate and affordable.

The neuropeptide cortistatin attenuates experimental autoimmune myocarditis via inhibition of cardiomyogenic T cell-driven inflammatory responses

BACKGROUND AND PURPOSE

Myocarditis is an inflammatory and autoimmune cardiovascular disease that causes dilated myocardiopathy and is responsible for high morbidity and mortality worldwide. Cortistatin is a neuropeptide produced by neurons and cells of the immune and vascular systems. Besides its action in locomotor activity and sleep, cortistatin inhibits inflammation in different experimental models of autoimmune diseases. However, its role in inflammatory cardiovascular disorders is unexplored. Here, we investigated the therapeutic effects of cortistatin in a well-established preclinical model of experimental autoimmune myocarditis (EAM).

EXPERIMENTAL APPROACH

We induced EAM by immunization with a fragment of cardiac myosin in susceptible Balb/c mice. Cortistatin was administered i.p. starting 7, 11 or 15 days after EAM induction. At day 21, we evaluated heart hypertrophy, myocardial injury, cardiac inflammatory infiltration and levels of serum and cardiac inflammatory cytokines, cortistatin and autoantibodies. We determined proliferation and cytokine production by heart draining lymph node cells in response to cardiac myosin restimulation.

KEY RESULTS

Systemic injection of cortistatin during the effector phase of the disease significantly reduced its prevalence and signs of heart hypertrophy and injury (decreased the levels of brain natriuretic peptide) and impaired myocardial inflammatory cell infiltration. This effect was accompanied by a reduction in self-antigen-specific T-cell responses in lymph nodes and in the levels of cardiomyogenic antibodies and inflammatory cytokines in serum and myocardium. Finally, we found a positive correlation between cardiac and systemic cortistatin levels and EAM severity.

CONCLUSIONS AND IMPLICATIONS

Cortistatin emerges as a new candidate to treat inflammatory dilated cardiomyopathy.

B-type natriuretic peptide-guided treatment for heart failure

BACKGROUND

Heart failure is a condition in which the heart does not pump enough blood to meet all the needs of the body. Symptoms of heart failure include breathlessness, fatigue and fluid retention. Outcomes for patients with heart failure are highly variable; however on average, these patients have a poor prognosis. Prognosis can be improved with early diagnosis and appropriate use of medical treatment, use of devices and transplantation. Patients with heart failure are high users of healthcare resources, not only due to drug and device treatments, but due to high costs of hospitalisation care. B-type natriuretic peptide levels are already used as biomarkers for diagnosis and prognosis of heart failure, but could offer to clinicians a possible tool to guide drug treatment. This could optimise drug management in heart failure patients whilst allaying concerns over potential side effects due to drug intolerance.

OBJECTIVES

To assess whether treatment guided by serial BNP or NT-proBNP (collectively referred to as NP) monitoring improves outcomes compared with treatment guided by clinical assessment alone.

SEARCH METHODS

Searches were conducted up to 15 March 2016 in the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library; MEDLINE (OVID), Embase (OVID), the Database of Abstracts of Reviews of Effects (DARE) and the NHS Economic Evaluation Database in the Cochrane Library. Searches were also conducted in the Science Citation Index Expanded, the Conference Proceedings Citation Index on Web of Science (Thomson Reuters), World Health Organization International Clinical Trials Registry and ClinicalTrials.gov. We applied no date or language restrictions.

SELECTION CRITERIA

We included randomised controlled trials of NP-guided treatment of heart failure versus treatment guided by clinical assessment alone with no restriction on follow-up. Adults treated for heart failure, in both in-hospital and out-of-hospital settings, and trials reporting a clinical outcome were included.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies for inclusion, extracted data and evaluated risk of bias. Risk ratios (RR) were calculated for dichotomous data, and pooled mean differences (MD) (with 95% confidence intervals (CI)) were calculated for continuous data. We contacted trial authors to obtain missing data. Using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach, we assessed the quality of the evidence and GRADE profiler (GRADEPRO) was used to import data from Review Manager to create a 'Summary of findings' table.

MAIN RESULTS

We included 18 randomised controlled trials with 3660 participants (range of mean age: 57 to 80 years) comparing NP-guided treatment with clinical assessment alone. The evidence for all-cause mortality using NP-guided treatment showed uncertainty (RR 0.87, 95% CI 0.76 to 1.01; patients = 3169; studies = 15; low quality of the evidence), and for heart failure mortality (RR 0.84, 95% CI 0.54 to 1.30; patients = 853; studies = 6; low quality of evidence).The evidence suggested heart failure admission was reduced by NP-guided treatment (38% versus 26%, RR 0.70, 95% CI 0.61 to 0.80; patients = 1928; studies = 10; low quality of evidence), but the evidence showed uncertainty for all-cause admission (57% versus 53%, RR 0.93, 95% CI 0.84 to 1.03; patients = 1142; studies = 6; low quality of evidence).Six studies reported on adverse events, however the results could not be pooled (patients = 1144; low quality of evidence). Only four studies provided cost of treatment results, three of these studies reported a lower cost for NP-guided treatment, whilst one reported a higher cost (results were not pooled; patients = 931, low quality of evidence). The evidence showed uncertainty for quality of life data (MD -0.03, 95% CI -1.18 to 1.13; patients = 1812; studies = 8; very low quality of evidence).We completed a 'Risk of bias' assessment for all studies. The impact of risk of bias from lack of blinding of outcome assessment and high attrition levels was examined by restricting analyses to only low 'Risk of bias' studies.

AUTHORS' CONCLUSIONS

In patients with heart failure low-quality evidence showed a reduction in heart failure admission with NP-guided treatment while low-quality evidence showed uncertainty in the effect of NP-guided treatment for all-cause mortality, heart failure mortality, and all-cause admission. Uncertainty in the effect was further shown by very low-quality evidence for patient's quality of life. The evidence for adverse events and cost of treatment was low quality and we were unable to pool results.

Impact of B-type natriuretic peptide (BNP) on development of atrial fibrillation in people with Type 2 diabetes

AIMS

To examine if a simple biomarker can identify people with diabetes who are at high risk of atrial fibrillation.

METHODS

A retrospective cohort study was conducted at a single centre in people with Type 2 diabetes referred to our department between January 2000 and December 2007. In 517 consecutive people without any history, signs or symptoms of atrial fibrillation at baseline, the association between baseline B-type natriuretic peptide level and future atrial fibrillation incidence was examined, with adjustments for other potentially confounding factors.

RESULTS

A total of 28 people were diagnosed with new-onset atrial fibrillation during a median 6-year follow-up. When people were categorized into three groups according to B-type natriuretic peptide clinical thresholds (20 and 100 pg/ml), hazard ratios for the development of atrial fibrillation in the middle and highest B-type natriuretic peptide groups were 2.8 and 9.4, respectively, compared with the lowest B-type natriuretic peptide group. Time-dependent receiver-operating curve analysis identified a threshold for B-type natriuretic peptide to detect atrial fibrillation development of 52.8 pg/ml (sensitivity 75.2%, specificity 68.8%). The B-type natriuretic peptide predictive value was independent of and similar to that of left atrial size and ventricular dimension.

CONCLUSION

In people with Type 2 diabetes, high baseline B-type natriuretic peptide levels were significantly associated with future atrial fibrillation development.

Left ventricular filling pressure assessed by exercise TDI was correlated with early HFNEF in patients with non-obstructive hypertrophic cardiomyopathy

BACKGROUND

Hypertrophic cardiomyopathy (HCM) patients are more susceptible to suffer from heart failure with normal ejection fraction (HFNEF). Therefore, it is critical to evaluate the relationship between left ventricular filling pressure (LVFP) and HFNEF, even if a large proportion of HCM patients have normal LVFP at rest. The objective was to assess the correlation between exercise tissue Doppler imaging (TDI) and early HFNEF in HCM patients by treadmill exercise echocardiography combined with cardiopulmonary exercise test (CPET).

METHOD

Twenty-seven non-obstructive HCM patients and 31 age- and gender-matched healthy volunteers were enrolled in this study. All subjects underwent treadmill exercise echocardiography combined with CPET. N-terminal pro-brain natriuretic peptide (NT-proBNP) levels were analyzed before and after exercise.

RESULT

Five HCM patients had normal LVFP at rest and increased after exercise. For this subgroup, the relationship between minute ventilation and carbon dioxide production (VE/VCO2 slope) and NT-proBNP levels were higher compared with controls and the subgroup with normal resting and stress LVFP, but was similar to the subgroup with elevated LVFP both at rest and after exercise.

CONCLUSION

Elevated LVFP after exercise suggested the occurrence of early HFNEF in patients with non-obstructive HCM.

Association of serum myeloid cells of soluble triggering receptor-1 level with myocardial dysfunction in patients with severe sepsis

OBJECTIVE

To investigate the association of serum sTREM-1 with myocardial dysfunction in patients with severe sepsis.

METHODS

A total of 85 patients with severe sepsis were divided into severe sepsis group (n = 40) and septic shock group (n = 45). Serum levels of sTREM-1, NT-proBNP, APACHE II score, SOFA score, cardiac index, cardiac function index, global ejection fraction, and left ventricular contractility index were measured on days 1, 3, and 7 after admission to ICU.

RESULTS

Serum sTREM-1 levels of patients with septic shock were significantly higher than those with severe sepsis on days 1, 3, and 7. Serum sTREM-1 was positively correlated with APACHE II scores, SOFA scores, and NT-proBNP. However, The sTREM-1 level was markedly negatively correlated with CI, CFI, GEF, and dP/dt max, respectively. Multiple logistic regression analysis showed that sTREM-1 was independent risk factor to NT-proBNP increasing. The optimal cut-off point of sTREM-1 for detecting patients with myocardial dysfunction was 468.05 ng/mL with sensitivity (80.6%) and specificity (75.7%). There is no difference in TREM-1-mRNA expression between the two groups.

CONCLUSIONS

Serum sTREM-1 is significantly associated with myocardial dysfunction and may be a valuable tool for determining the presence of myocardial dysfunction in patients with severe sepsis.

Heart Failure with Preserved Ejection Fraction – A Review

Heart failure with preserved left ventricular ejection fraction (HF-PEF), sometimes named diastolic heart failure, is a common condition most frequently seen in the elderly and is associated with arterial hypertension and left ventricular (LV) hypertrophy. Symptoms are attributed to a stiff left ventricle with compensatory elevation of filling pressure and reduced ability to increase stroke volume by the Frank-Starling mechanism. LV interaction with stiff arteries aggravates these problems. Prognosis is almost as severe as for heart failure with reduced ejection fraction (HF-REF), in part reflecting co-morbidities. Before the diagnosis of HF-PEF is made, non-cardiac etiologies must be excluded. Due to the non-specific nature of heart failure symptoms, it is essential to search for objective evidence of diastolic dysfunction which, in the absence of invasive data, is done by echocardiography and demonstration of signs of elevated LV filling pressure, impaired LV relaxation, or increased LV diastolic stiffness. Antihypertensive treatment can effectively prevent HF-PEF. Treatment of HF-PEF is symptomatic, with similar drugs as in HF-REF.

Diastolic function in pregnant patients with cardiac symptoms

OBJECTIVE

Dyspnea on exertion and peripheral edema occur routinely during normal gestational stage, making early diagnosis of congestive heart failure (CHF) during pregnancy difficult. Abnormal left ventricular (LV) diastolic function may be associated with dyspnea on exertion and peripheral edema, and brain natriuretic peptide (BNP) correlates with volume overload in nonpregnant populations. We tested the hypothesis that abnormal echocardiographic diastolic parameters and elevated BNP correlate in symptomatic pregnant patients.

METHODS

Sixty-six gravidas presented to an Obstetric Cardiology Clinic were analyzed. Data including symptoms of CHF, BNP, and maternal and gestational ages were recorded. Echocardiograms were reviewed to measure the diastolic parameters E, A, e', and a' wave velocities and left atrial volume index (LAVI). Logistic regression was performed to characterize the relationship between diastolic parameters and BNP.

RESULTS

Among the 66 pregnant patients included in the analysis, only 6 were found to have significant LV systolic dysfunction. LAVI, E, and E/e' ratio correlated positively with BNP in this symptomatic population (p = 0.008, 0.007, and 0.002, respectively).

CONCLUSIONS

Abnormal diastolic parameters that represent increased LV filling pressures correlated with higher BNP levels in pregnant patients with symptoms of CHF. This suggests that symptoms may be due to diastolic dysfunction, and BNP levels may identify elevated LV filling pressures in symptomatic pregnant patients.

Reliability and validity of the Korean version of the Minnesota Living with Heart Failure Questionnaire

OBJECTIVE

The aim of this study was to verify the reliability and validity of the Korean language version of the Minnesota Living with Heart Failure Questionnaire (MLHFQ) before using this version in clinical practice to assess the quality of care in patients with heart failure in a cardiology clinic.

METHODS

The Korean versions of the MLHFQ, 36-Item Short Form Health Survey, and Center for Epidemiologic Studies Depression Scale were administered to evaluate the psychometric properties among 154 patients with heart failure in a major cardiac center in Korea. Cardiac function was assessed by evaluating left ventricular ejection fraction values, N-terminal pro-brain natriuretic peptide levels, and New York Heart Association classifications.

RESULTS

The questionnaire content and construct validity were supported by factor analysis. Three factors explained 70.7% of the variance. Total and subtotal scales had correlations with the mental and physical component scores of the 36-Item Short Form Health Survey and Center for Epidemiologic Studies Depression Scale, supporting the convergent validity of the Korean version of the MLHFQ. We also found that the New York Heart Association classification was associated with the MLHFQ score. The internal consistency of both total and subtotal scales was greater than .80.

CONCLUSION

The Korean version of the MLHFQ demonstrated excellent psychometric properties. These results support the use of the MLHFQ in Korean patients with heart failure. Further studies are recommended to assess the responsiveness to change of the Korean version of the MLHFQ.

Diabetic neuropathy and heart failure: role of neuropeptides

Cardiovascular autonomic neuropathy (CAN), in which patients present with damage of autonomic nerve fibres, is one of the most common complications of diabetes. CAN leads to abnormalities in heart rate and vascular dynamics, which are features of diabetic heart failure. Dysregulated neurohormonal activation, an outcome of diabetic neuropathy, has a significant pathophysiological role in diabetes-associated cardiovascular disease. Key players in neurohormonal activation include cardioprotective neuropeptides and their receptors, such as substance P (SP), neuropeptide Y (NPY), calcitonin-gene-related peptide (CGRP), atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and C-type natriuretic peptide (CNP). These neuropeptides are released from the peripheral or autonomic nervous system and have vasoactive properties. They are further implicated in cardiomyocyte hypertrophy, calcium homeostasis, ischaemia-induced angiogenesis, protein kinase C signalling and the renin-angiotensin-aldosterone system. Therefore, dysregulation of the expression of neuropeptides or activation of the neuropeptide signalling pathways can negatively affect cardiac homeostasis. Targeting neuropeptides and their signalling pathways might thus serve as new therapeutic interventions in the treatment of heart failure associated with diabetes. This review discusses how neuropeptide dysregulation in diabetes might affect cardiac functions that contribute to the development of heart failure.

Natriuretic Peptide testing in primary care

The incidence, as well as the morbidity and mortality associated with heart failure (HF) continue to rise despite advances in diagnostics and therapeutics. A recent advance in the diagnostic and therapeutic approach to HF is the use of natriuretic peptide (NP) testing, including both B-type natriuretic peptide (BNP) and its amino terminal cleavage equivalent (NT-proBNP). NPs may be elevated at an early stage among those with symptoms as well among those without. The optimal approach for applying NP testing in general populations is to select the target population and optimal cut off values carefully. Superior diagnostic performance is observed among those with higher baseline risk (such as hypertensives or diabetics). As well, unlike for acute HF, the cut off value for outpatient testing for BNP is 20-40 pg/mL and for NTproBNP it is 100-150 ng/L. In symptomatic primary care patients, both BNP and NT-proBNP serve as excellent tools for excluding HF based on their excellent negative predictive values and their use may be cost effective. Among those with established HF, it is logical to assume that titration of treatment to achieve lower NPs levels may be advantageous. There are several ongoing trials looking at that prospect.

B-type natriuretic peptide predicts long-term survival after major non-cardiac surgery

BACKGROUND

The prediction of long-term survival after surgery is complex. Natriuretic peptides can predict short-term postoperative cardiac morbidity and mortality. This study aims to determine the long-term prognostic significance of preoperative B-type natriuretic peptide (BNP) concentration after major non-cardiac surgery.

METHODS

We conducted a prospective single-centre observational cohort study in a West of Scotland teaching hospital. Three hundred and forty-five patients undergoing major non-cardiac surgery were included. The primary endpoint was long-term all-cause mortality.

RESULTS

Overall survival was 67.8% (234/345), with 27 postoperative deaths (within 42 days) and 84 deaths at subsequent follow-up (median follow-up 953 days). A BNP concentration of >87.5 pg ml(-1) best predicted mortality, and the mean survival of patients with an elevated BNP (>87.5 pg ml(-1)) was 731.9 (95% CI 613.6-850.2) days compared with 1284.6 days [(95% CI 1219.3-1350.0), P<0.001] in patients with a BNP<87.5 pg ml(-1). BNP was an independent predictor of survival.

CONCLUSIONS

BNP is an independent predictor of long-term survival after major non-cardiac surgery. A simple preoperative blood test can provide predictive information on future risk of death, and potentially has a role in preoperative risk assessment.

The pro-BNP Serum Level and Echocardiographic Tissue Doppler Abnormalities in Patients with Beta Thalassemia Major

Background

Doppler echocardiographic studies of the left ventricle (LV) function in patients with β-Thalassemia Major (β-TM) had shown different patterns of systolic and diastolic dysfunctions associated with abnormal serum brain natriuretic peptide (BNP).

Aim

This cross-sectional study was designed to study the LV systolic and diastolic functions and correlate that with serum level of N-terminal pro brain natriuretic hormone (NT- pro BNP) in patients with β-TM using Pulsed Doppler (PD) and Tissue Doppler (TD) echocardiography.

Methods

The study was conducted on patients with β-TM (n = 38, age 15.7 ± 8.9 years) and compared with an age-matched controls (n = 38, age 15.9 ± 8.9 years). In all participants, PD and TD echocardiography were performed and blood samples were withdrawn for measuring the serum level of NT-pro BNP, ferritin, and alanine transaminase.

Results

Patients with β-TM compared with controls, have thicker LV septal wall index (0.65 ± 0.26 vs. 0.44 ± 0.21 cm, P < 0.001), posterior wall index (0.65 ± 0.23 vs. 0.43 ± 0.21 cm, P < 0.01), and larger LVEDD index (4.35 ± 0.69 vs.3.88 ± 0.153 mm, P < 0.001). In addition, β-TM patients have higher transmitral E wave velocity (E) (70.818 ± 10.139 vs. 57.532 ± 10.139, p = 0.027) and E/A ratio (1.54 ± 0.17 vs. 1.23 ± 0.19, P < 0.01) and shorter deceleration time (DT) (160.13 ± 13.3 vs. 170.50 ± 19.20 m sec, P < 0.01). Furthermore, the ratio of transmitral E wave velocity to the tissue Doppler E wave at the basal septal mitral annulus (E/Em⁻) was significantly higher in β-TM group (19.6 ± 2.81 vs. 13.868 ± 1.41, P < 0.05). The tissue doppler systolic wave (Sm) velocity and the early diastolic wave (Em) were significantly lower in β-TM group compared to controls (Sm: 4.82 ± 1.2 vs. 6.22 ± 2.1 mm/sec, P < 0.05; Em: 3.51 ± 2.7 vs. 4.12 ± 2.5 mm/sec P < 0.05, respectively). The tricuspid valve velocity was significantly higher in β-TM patients compared with controls (2.993 ± 0.569 vs. 1.93 ± 0.471 m/sec, respectively, P < 0.01). The mean serum NT pro-BNP in β-TM was significantly higher compared with controls (37.6 ± 14.73 vs. 5.5 ± 5.4pg/ml, P < 0.05). The left ventricle ejection fraction (EF%) and fractional shortening (FS%) were not significantly different between both groups.

Conclusion

We conclude that patients with β-TM had a significantly higher serum level of NT-pro BNP that is positively correlated with the E/Em ratio on tissue Doppler. Furthermore, we confirm our previous findings that patients with β-TM exhibit LV diastolic pattern on echocardiogram suggestive of restrictive type with well preserved left ventricle systolic function.

Age-dependent values of N-terminal pro-B-type natriuretic peptide are superior to a single cut-point for ruling out suspected systolic dysfunction in primary care

AIMS

The study evaluated the use of age-related decision limits for N-terminal pro-B-type natriuretic peptide (NT-proBNP), for ruling out suspected systolic dysfunction in symptomatic patients in primary care, compared with the present standards.

METHODS AND RESULTS

Data were obtained from 5508 patients from 10 studies in the UK, New Zealand, Europe, and USA. All have had NT-proBNP analysis and echocardiography. The median age was 62 years (range 18-100 years) with a prevalence of reduced left ventricular systolic function (left ventricular ejection fraction < or =40%) of 18%. In a receiver operating characteristic curve analysis, overall area under the curve (AUC) was 0.89. When looking at different age groups, AUC was highest (0.95) for <50 years, intermediate (0.90) for 50-75 years, and lowest (0.82) for >75 years. Using optimized decision limits, sensitivity, specificity, and negative predictive values (NPVs) were: <50 years (50 ng/L): 99.2, 57.2, and 99.7%; 50-75 years (75 ng/L): 95.9, 51.0, and 96.8%; and >75 years (250 ng/L): 87.9, 53.7, and 92.4%, respectively. Using only a single decision value (125 ng/L for all ages) gave sensitivities of 89.1, 91.9, and 94.3%; specificities of 84.0, 69.1, and 29.3% and NPVs of 97.7, 97.6, and 93.4%. A decision value of 400 ng/L for all ages gave much lower sensitivities.

CONCLUSION

In a large population of patients in primary care, the use of age-stratified NT-proBNP decision limits considerably improves performance over current standards, with an excellent NPV for exclusion of reduced left ventricular systolic function.

Application of classic heart failure definitions of asymptomatic and symptomatic ventricular dysfunction and heart failure symptoms with preserved ejection fraction to patients with systemic right ventricles

Heart failure guidelines classify patients into subgroups with asymptomatic versus symptomatic ventricular dysfunction versus heart failure with a preserved ejection fraction. In this study, this approach was applied in a series of patients with complete transposition of the great arteries after atrial switch to assess to what extent this classification fits patients with systemic right ventricles. The study included stable adult patients after atrial switch, stratified according to preserved versus impaired systolic function (fractional area change > or =0.40 vs <0.40), absence versus presence of symptoms, absence versus presence of significant tricuspid regurgitation (TR), and normal versus elevated brain natriuretic peptide (BNP) levels. Twenty-two of 42 participants (52.4%; mean age 18.2 +/- 2.8 years) had preserved systolic function, and 20 (47.6%) had impaired systolic function; 10 patients (23.8%) had asymptomatic right ventricular (RV) dysfunction. The latter more frequently had significant TR (p = 0.04) and elevated BNP levels (p = 0.008), compared with asymptomatic patients with preserved systolic function. Normal BNP levels independently predicted preserved RV function in all patients (odds ratio 6.4, 95% confidence interval 1.03 to 39.1, p = 0.04) and in asymptomatic patients (odds ratio 14.4, 95% confidence interval 1.2 to 176.2, p = 0.03). Heart failure symptoms with preserved systolic function were present in 5 patients (11.9%), including 3 patients with significant TR. In conclusion, asymptomatic RV dysfunction and heart failure symptoms with preserved systolic function are common in patients with systemic right ventricles. BNP levels can be used to predict preserved systolic RV function, especially in asymptomatic patients. Heart failure symptoms with preserved RV systolic function can be frequently explained by the coexistence of significant TR.

The accuracy of symptoms, signs and diagnostic tests in the diagnosis of left ventricular dysfunction in primary care: a diagnostic accuracy systematic review

BACKGROUND

To assess the accuracy of findings from the clinical history, symptoms, signs and diagnostic tests (ECG, CXR and natriuretic peptides) in relation to the diagnosis of left ventricular systolic dysfunction (LVSD) in a primary care setting.

METHODS

Diagnostic accuracy systematic review, we searched Medline (1966 to March 2008), EMBASE (1988 to March 2008), Central, Cochrane and ZETOC using a diagnostic accuracy search filter. We included cross-sectional or cohort studies that assess the diagnostic utility of clinical history, symptoms, signs and diagnostic tests, against a reference standard of echocardiography. We calculated pooled positive and negative likelihood ratios and assessed heterogeneity using the I2 index.

RESULTS

24 studies incorporating 10,710 patients were included. The median prevalence of LVSD was 29.9% (inter-quartile range 14% to 37%). No item from the clinical history or symptoms provided sufficient diagnostic information to "rule in" or "rule out" LVSD. Displaced apex beat shows a convincing diagnostic effect with a pooled positive likelihood ratio of 16.0 (8.2-30.9) but this finding occurs infrequently in patients. ECG was the most widely studied diagnostic test, the negative likelihood ratio ranging from 0.06 to 0.6. Natriuretic peptide results were strongly heterogeneous, with negative likelihood ratios ranging from 0.02 to 0.80.

CONCLUSION

Findings from the clinical history and examination are insufficient to "rule in" or "rule out" a diagnosis of LVSD in primary care settings. BNP and ECG measurement appear to have similar diagnostic utility and are most useful in "ruling out" LVSD with a normal test result when the probability of LVSD is in the intermediate range.

BNP in the community — Still work to be done…

The role of brain natriuretic peptide (BNP) as a screening tool for left ventricular systolic dysfunction (LVSD) in primary care remains unclear. We compared the efficacy of BNP with that of a 12 lead electrocardiogram (ECG) as a screening tool for LVSD in the setting of open access echocardiography and found BNP to be more sensitive in excluding LVSD than an ECG. The use of BNP in screening for LVSD resulted in a saving of 10 pounds per patient.

Evidence for the use of B-type natriuretic peptides for screening asymptomatic populations and for diagnosis in primary care

OBJECTIVES

To determine the screening and diagnostic properties of BNP and NT-proBNP for heart failure in primary care.

DESIGN AND METHODS

We conducted a systematic review of randomized control trials and observational (cohort or case-control) studies of heart failure detection using B-type natriuretic peptides published in English from January 1989 to February 2005. We extracted or calculated sensitivity, specificity, positive and negative likelihood ratios, area under the receiver-operator characteristic curve and diagnostic odds ratio (DOR).

RESULTS

We included 17 studies (7 screening, 9 diagnosis in primary care or specialised clinic, 1 both). There was considerable heterogeneity within the study populations, reference standard for diagnosis, and B-type natriuretic peptide decision point. Sensitivity ranged from 26% to 98%; and specificity from 44% to 88%. For screening, the Diagnostic Odds Ratio (DOR) ranged from 2.7 to 29, and for diagnosis from 2.8 to 137.

CONCLUSIONS

The performance characteristics of B-type natriuretic peptides measurement are not suitable for screening asymptomatic patients. For diagnosis in primary care, low B-type natriuretic peptide values may be used to rule-out heart failure but, due to poor specificity, high values cannot be used to rule-in the condition.

Neurohormonal activation and diagnostic value of cardiac peptides in patients with suspected mild heart failure

BACKGROUND

Data describing activation of brain natriuretic peptide (BNP) system relative to the renin-angiotensin-aldosterone system (RAAS) are sparse in the early phase of heart failure (HF).

AIMS

To compare activation of BNP system relative to RAAS hyperactivity and to assess diagnostic accuracy of cardiac peptides to detect any left ventricular dysfunction (LVD) in patients referred from primary care with suspected HF before institution of medical therapy.

METHODS

Of 166 referred patients 150 were consecutively included (14 were excluded and two refused consent). Echocardiography and measurements of neurohormonal activity were performed. Systolic dysfunction (LVSD) was defined as an ejection fraction<or=0.45. Abnormal left ventricular filling was determined by a combination of Doppler techniques.

RESULTS

LVSD with concomitant abnormal left ventricular filling was present in 22 patients, and abnormalities in left ventricular filling alone were present in 58. Median BNP were 307 and 37 pg/ml while median N-terminal proBNP (NT-proBNP) were 2285 and 199 pg/ml in the two groups respectively, and were significantly lower in patients without LVD (BNP: 8 pg/ml and NT-proBNP: 55 pg/ml, P<0.0001). NT-proBNP demonstrated a weak negative correlation with renin (r=-0.18, P=0.03) and aldosterone (r=-0.18, P=0.03), but no significant correlation with Ang II (r=-0.14, P=0.10) or noradrenaline (r=0.11, P=0.19). Renin correlated well with Ang II (r=0.85, P<0.0001), and aldosterone (r=0.41, P<0.0001). RAAS and noradrenaline demonstrated no diagnostic potential for the diagnosis of any LVD with areas under ROC curves close to 0.50. The area was 0.93 (95% CI 0.90-0.98) for BNP and 0.95 (0.91-0.99) for NT-proBNP. In 5-10% of patients with LVD, BNP and NT-proBNP were under the selected thresholds.

CONCLUSION

Patients with LVD demonstrated considerable activation of the BNP system, whereas RAAS hyperactivity could not be demonstrated. Thus, BNP and NT-proBNP had a considerable diagnostic potential even in patients with mild HF.

Use of a B-type natriuretic peptide in evaluating the treatment response of a relapsed lymphoma with cardiac involvement

A 50-year-old woman received a diagnosis of diffuse large B-cell non-Hodgkin's lymphoma in 2000 and achieved complete remission. In April 2004, echocardiography and computed tomography examinations identified a tumor attached to the tricuspid valve and protruding within the right atrium. Bone marrow and lymph node biopsies showed a relapse of large cell lymphoma. The patient had a markedly elevated level of B-type natriuretic peptide (BNP) but a normal level of cardiac troponin I. The follow-up evaluation of the BNP level after chemotherapy showed that it had returned to within normal limits, and an echocardiogram showed regression of the tumor. Use of the BNP level as a monitor in the treatment of cardiac lymphoma has never been reported. This article is the first to report the use of BNP monitoring before and after chemotherapy to evaluate a patient with an unusual relapsed lymphoma with cardiac involvement.

B-Type Natriuretic Peptide (BNP) and N-Terminal Pro-BNP in Obese Patients without Heart Failure: Relationship to Body Mass Index and Gastric Bypass Surgery

Background: Further investigations are warranted to better characterize variables that may confound the clinical interpretation of plasma natriuretic peptide measurements, which are increasingly recognized to have diagnostic and predictive importance.

Methods: Blood samples (EDTA plasma) from patients (n = 206) attending clinics for the medical treatment and follow-up of obesity were analyzed for B-type natriuretic peptide (BNP; Bayer assay) and the N-terminal segment of its prohormone (NT-proBNP; Roche assay). Natriuretic peptide concentration ranges were evaluated in those without diagnosis of congestive heart failure (CHF) or chronic kidney disease (CKD).

Results: BNP and NT-proBNP were directly correlated (r = 0.87; P = 0.01), with NT-proBNP concentrations higher relative to BNP. Of obese patients without CHF or CKD, 21.6% (40 of 185) had NT-proBNP concentrations greater than the published assay upper reference limit. Concentrations of both natriuretic peptides were higher in patients currently exposed to beta blockers, patients with the diagnosis of hypertension or type 2 diabetes, and patients with a history of gastric bypass surgery. An inverse relationship between body mass index (BMI) and both BNP and NT-proBNP was evident. According to the National Institutes of Health, National Heart, Lung, and Blood Institute classification, more than 95% of the participants sampled in this study were either obesity class 2 (35 kg/m2 &lt; BMI &lt; 39.9 kg/m2) or class 3 (BMI ≥40 kg/m2)

Conclusions: A substantial proportion of obese patients without CHF or CKD have concentrations greater than the upper reference limit for NT-proBNP but not for simultaneously measured BNP. A history of gastric bypass surgery appeared to be a significant predictor of increased natriuretic peptide concentrations when assessed in a population of patients with class 2 or 3 obesity.

Brain Natriuretic Peptide is Produced Both by Cardiomyocytes and Cells Infiltrating the Heart in Patients with Severe Heart Failure Supported by a Left Ventricular Assist Device

BACKGROUND

Brain natriuretic peptide (BNP) is a cardiac neurohormone synthesized in cardiac ventricles as a result of increased wall stress. Left ventricular assist device (LVAD) support in patients with end-stage heart failure results in reduced wall stress and therefore may change BNP levels in the heart.

METHODS

BNP plasma levels were measured in 17 patients with end-stage HF before LVAD implantation and at 1 week, 1 month, and 3 months after LVAD support. BNP-messenger RNA (mRNA) expression in cardiac biopsy specimens of 27 patients before and after LVAD support was determined by quantitative polymerase chain reaction. Immunohistochemistry (IHC) and IHC-double staining was used in biopsy specimens from 32 patients before and after LVAD support to localize the BNP protein expression in the heart.

RESULTS

BNP plasma levels significantly decreased from 1,872 +/- 1,098 pg/ml before implantation to 117 +/- 91 pg/ml at 3 months after LVAD implantation. This decrease in plasma levels was accompanied by a significant decrease in mRNA expression (relative quantity) in the heart. IHC and IHC-double staining showed BNP immunoreactivity in the cardiomyocytes, endothelial cells, infiltrating T cells, and macrophages.

CONCLUSIONS

The significant decrease in serum BNP concentration after LVAD support coincides with a decrease in BNP mRNA and protein expression in the heart. BNP is produced in the left ventricle not only by cardiomyocytes but also by endothelial cells, T cells, and macrophages. Unloading of the left ventricle by a LVAD results in decreased BNP expression in the heart and plasma and may play an important role in the reverse remodeling process of the heart.

Cardiac biomarkers: a contemporary status report

The field of cardiac biomarkers has grown by leaps and bounds in the past two decades. In this review we try to summarize the explosion of emerging knowledge and address the roles of some of the biomarkers that have either proven or potential utility. We detail some of the markers of ischemia, hemodynamic markers of heart failure, inflammatory markers, and the novel and innovative approach of combining these for a multimarker strategy. At the end of this review we highlight some of the biomarker-guided approaches and strategies that might lead to better and more-effective care of patients.

Comparative sensitivities between different plasma B-type natriuretic peptide assays in patients with minimally symptomatic heart failure

Plasma B-type natriuretic peptide (BNP) assays have become widely used to diagnose and manage patients with heart failure. However, differences in assay characteristics may have important implications when BNP is used as a screening test for heart failure at a specific cutoff value. We performed a prospective comparison of 2 commercially available assays--one that is a laboratory-based, microparticle enzyme immunoassay (MEIA) that uses EDTA plasma specimens and one that is a point-of-care (POC), single-use fluorescence immunoassay that uses EDTA--anticoagulated whole blood or plasma specimens-in patients with heart failure and healthy controls. Despite the overall concordance between different SNP assays for the diagnosis of heart failure, their sensitivities may differ when compared at the approved diagnostic cutoff value of 100 pg/mL. At this cutoff value, the MEIA on AxSYM demonstrated greater sensitivity than POC Triage BNP assay in minimally symptomatic patients with heart failure. Therefore, for screening purposes, cutoff values for plasma BNP or N-terminal pro-BNP levels should be specific for each assay to optimize test performance. These findings suggest that there is a relationship between the decision statistics used in screening for left ventricular dysfunction and the type of diagnostic assay used.

Early recognition and treatment of hypertensive heart disease

PURPOSE OF REVIEW

Hypertension leads to left ventricular hypertrophy, diastolic dysfunction, and eventually clinical heart failure (hypertensive heart disease). There is an important need for physicians to recognize this entity, understand its pathophysiology, and become fluent in treatment options available. This review of recent basic science and clinical data serves to accomplish this task.

RECENT FINDINGS

In the past year, a number of exciting concepts have come to the forefront. First, data on the use of brain natriuretic peptide as a screening biomarker has shown promise in patients with symptoms of heart failure. For the earliest detection of structural changes, serum propeptide of procollagen type I, a marker of the deposition of type I collagen in the cardiac interstitium provides a noninvasive way to quantify myocardial fibrosis. Treatment options in the past few years have focused heavily on the anti-fibrotic effects of inhibitors of the renin-angiotensin-aldosterone system, perhaps supplanting beta blockers as first-line agents to regress left ventricular hypertrophy. The concept of aldosterone escape is discussed, highlighting the importance of aldosterone inhibitors in these patients. Lastly, we provide a comprehensive review of all antihypertensive classes and their effects on hypertensive heart disease.

SUMMARY

The incidence of hypertensive heart disease is increasing. Earlier detection may be possible with newly studied serum biomarkers. All anti-hypertensive treatments have shown improvement in regressing left ventricular hypertrophy, but inhibitors of the renin-angiotensin-aldosterone system possess the most potent anti-fibrotic effects. It is increasingly important for clinicians to identify and manage hypertensive heart disease to prevent increased morbidity and mortality.

Evaluation of B-type natriuretic peptide (BNP) levels in normal and preeclamptic women

OBJECTIVE

B-type natriuretic peptide (BNP) is synthesized in cardiac ventricles in response to volume expansion. This study evaluated BNP levels to determine trends during pregnancy, and to assess BNP as a diagnostic tool in preeclampsia.

STUDY DESIGN

We studied 163 BNP levels in 118 pregnant women, ranging from first trimester to term. An additional 34 patients with preeclampsia were studied and compared to 25 normal control patients at term. Plasma BNP values were determined using a standard assay.

RESULTS

The median BNP levels during the 1st, 2nd, 3rd trimester, and at term were equivalent (18.4, 17.9, 15.5, and 17.8 pg/mL, respectively, P = .796). The median BNP levels in normal patients, mild preeclamptics, and severe preeclamptics were 17.8, 21.1, and 101 pg/mL, respectively, with the severe group being significantly higher than the mild group (P = .003) and any phase of normal pregnancy (P < .001 in each case). A BNP cut-off of <40.6 pg/mL had a negative predictive value of 92% in excluding preeclampsia.

CONCLUSION

In normal pregnancies, median BNP values are <20 pg/mL, and stable throughout gestation. In severe preeclampsia BNP levels are elevated. This may reflect ventricular stress and/or subclinical cardiac dysfunction associated with preeclampsia.

Understanding B-type natriuretic peptide and its role in diagnosing and monitoring congestive heart failure

Congestive heart failure (CHF) is a complex clinical syndrome characterized by dysfunction of the left, right, or both ventricles, which results in the impairment of the heart's ability to circulate blood at a rate sufficient to maintain the metabolic needs of peripheral tissues and various organs. Owing to the drastic increase in cardiovascular risk factors such as obesity, diabetes, and improved survival rate after acute myocardial infarction and subsequent development of CHF in the last quarter of a century, CHF has become a major and increasing cause of death and disability in the United States. Unfortunately, the signs and symptoms are nonspecific for CHF Also, routine laboratory values, electrocardiograms, and X-rays are not always accurate enough to make the appropriate diagnosis. Recently, the US Food and Drug Administration approved a new biomarker, B-type natriuretic peptide (BNP), for the purpose of diagnosing and assessing severity of CHE BNP is synthesized, stored, and released primarily by the ventricular myocardium in response to volume expansion and pressure overload. The use of SNP, along with other diagnostic tools, can enable care providers to facilitate and optimize care of heart failure patients in a variety of clinical settings. Emerging clinical data will help further refine biomarker-guided therapeutic and monitoring strategies involving BNP.