Brain natriuretic peptide (BNP) testing in the emergency department

A review of biosensors for the detection of B-type natriuretic peptide as an important cardiovascular biomarker

Heart disease, as the most serious threat to human health globally, is responsible for rising mortality rates, largely due to lifestyle and diet. Unfortunately, the main problem for patients at high risk of heart disease is the validation of prognostic tests. To this end, the detection of cardiovascular biomarkers has been employed to obtain pathological and physiological information in order to improve prognosis and early-stage diagnosis of chronic heart failure. Short-term changes in B-type natriuretic peptide are known as a standard and important biomarker for diagnosis of heart failure. The most important problem for detection is low concentration and short half-life in the blood. The normal concentration of BNP in blood is less than 7 nM (25 pg/mL), which increases significantly to more than 80 pg/mL. Therefore, the development of new biosensors with better sensitivity, detection limit, and dynamic range than current commercial kits is urgently needed. This review classifies the biosensors designed for detection of BNP into electrochemical, optical, microfluidic, and lateral-flow immunoassay techniques. The review clearly demonstrates that a variety of immunoassay, aptasensor, enzymatic and catalytic nanomaterials, and fluorophores have been successfully employed for detection of BNP at low attomolar ranges. Dtection of B-type natriuretic peptide with biosensors.

Modified Natriuretic Peptides and their Potential Role in Cancer Treatment

The natriuretic peptide family (NPs) is a group of natural endocrine hormones, containing a 17-amino acid ring structure connected by disulfide bonds of two cysteines. In this review, the members of the natriuretic peptide family and their corresponding receptors as well as the anti-cancer effects are introduced. Four cardiac hormones of NPs (ANP, VD, KP and LANP) can effectively inhibit the growth of human small cell lung cancer, breast cancer and other tumors and significantly reduce tumor volume in vivo. The in vitro experiments also show that cardiac hormones, CNP and urodilatin can effectively inhibit the growth of most tumor cells. We then further summarized the anti-cancer mechanism of natriuretic peptides. Finally, we introduce several methods that modify natriuretic peptides, leading to enhance their stability and prolong the biological effects of these peptides, which might be helpful for the clinical application in the future. Peptide therapy is a very promising field for cancer treatments since they can induce the death of cancer cells without dramatically affecting normal cells. The synthesis of a useful and stable natriuretic peptide can enhance the effect of cancer treatments and significantly reduce drug resistance and toxicity.

Metabolic and immunological evaluation of patients with indeterminate and cardiac forms of Chagas disease

Chagas disease affects approximately 7 million people, causing disability and mortality in the most productive life stages of infected individuals. Considering the lifestyle of the world population, metabolic syndrome is a synergistic factor for an increased cardiovascular risk of patients with Chagas disease.This study transversally evaluated the metabolic and immunological profiles of patients with indeterminate (IF) and cardiac (CF) forms of Chagas disease and their correlations with left ventricular dysfunction (LVD).Clinical and electrical bioimpedance analysis, levels of cytokines (interferon [IFN]-γ, tumor necrosis factor [TNF]-α, interleukin [IL]-17, IL-10, and IL-33) and adipocytokines (adiponectin, leptin, and resistin), metabolic syndrome components, and brain natriuretic peptide (BNP) levels were assessed in 57 patients (13 IF and 44 CF) with a mean age of 61.63 ± 12.1 years. Chest x-ray, electrocardiogram, and echocardiogram were performed to classify the clinical forms.The CF group had a higher number of individuals with metabolic syndrome components blood pressure altered, while more participants in the CF group with LVD had low high-density lipoprotein (HDL) levels. The IF group had more participants with a higher waist-to-hip ratio (WHR). No significant difference was observed between metabolic syndrome, cytokine and adipocytokine level, and clinical forms of the disease or in relation to LVD.Individuals with the IF showed metabolic and immunological profiles compatible with increased disease control, whereas those with CF showed marked inflammatory immune response.

The plasma level of mCRP is linked to cardiovascular disease in antineutrophil cytoplasmic antibody-associated vasculitis

BACKGROUND

C-reactive protein (CRP) has two natural isomers: C-reactive protein pentamer (pCRP) and C-reactive protein monomer (mCRP). The levels of CRP are significantly elevated in patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). mCRP not only activates the endothelial cells, platelets, leukocytes, and complements, but also has a proinflammatory structural subtype that can localize and deposit in inflammatory tissues. Thus, it regulates a variety of clinical diseases, such as ischemia/reperfusion (I/R) injury, Alzheimer's disease, age-related macular degeneration, and cardiovascular disease. We hypothesized that plasma mCRP levels are related to cardiovascular disease in AAV.

METHODS

In this cross-sectional study, 37 patients with AAV were assessed. Brain natriuretic peptide (BNP) and mCRP in plasma were assessed by enzyme-linked immunosorbent assay (ELISA). The acute ST-segment elevation myocardial infarction (STEMI) was diagnosed by coronary angiography, and the Gensini score calculated. Echocardiography evaluated the ejection fraction (EF%), left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), and left ventricular mass index (LVMI). Estimated glomerular filtration rate (eGFR) was calculated based on serum creatinine, age, and gender.

RESULTS

The plasma level of mCRP in AAV was significantly higher than that in healthy volunteers (P < 0.001). Then, mCRP and CRP levels were compared with and without STEMI complications in AAV. The plasma level of mCRP was higher, but that of CRP was lower in STEMI. The plasma level of mCRP was correlated with Birmingham vasculitis activity score (BVAS), eGFR, BNP, EF%, LVEDV, LVESV, LVMI, and STEMI complications' Gensini score in AAV; however, CRP did not correlate with BNP, EF%, LVEDV, LVESV, LVMI, and Gensini score.

CONCLUSIONS

The plasma level of mCRP was related to cardiovascular diseases in AAV patients.

Diagnosis of Acute Heart Failure in the Emergency Department: An Evidence-Based Review

Heart failure is a common presentation to the emergency department (ED), which can be confused with other clinical conditions. This review provides an evidence-based summary of the current ED evaluation of heart failure. Acute heart failure is the gradual or rapid decompensation of heart failure, resulting from either fluid overload or maldistribution. Typical symptoms can include dyspnea, orthopnea, or systemic edema. The physical examination may reveal pulmonary rales, an S3 heart sound, or extremity edema. However, physical examination findings are often not sensitive or specific. ED assessments may include electrocardiogram, complete blood count, basic metabolic profile, liver function tests, troponin, brain natriuretic peptide, and a chest radiograph. While often used, natriuretic peptides do not significantly change ED treatment, mortality, or readmission rates, although they may decrease hospital length of stay and total cost. Chest radiograph findings are not definitive, and several other conditions may mimic radiograph findings. A more reliable modality is point-of-care ultrasound, which can facilitate the diagnosis by assessing for B-lines, cardiac function, and inferior vena cava size. These modalities, combined with clinical assessment and gestalt, are recommended.

Point-of-care diagnostics for niche applications

Point-of-care or point-of-use diagnostics are analytical devices that provide clinically relevant information without the need for a core clinical laboratory. In this review we define point-of-care diagnostics as portable versions of assays performed in a traditional clinical chemistry laboratory. This review discusses five areas relevant to human and animal health where increased attention could produce significant impact: veterinary medicine, space travel, sports medicine, emergency medicine, and operating room efficiency. For each of these areas, clinical need, available commercial products, and ongoing research into new devices are highlighted.

Diagnosing and managing acute heart failure in the emergency department

Heart failure is a clinical syndrome that results from the impairment of ventricular filling or ejection of blood and affects millions of people worldwide. Diagnosis may not be straightforward and at times may be difficult in an undifferentiated patient. However, rapid evaluation and diagnosis is important for the optimal management of acute heart failure. We review the many aspects of diagnosing and treating acute heart failure in the emergency department.

Transfusion-related acute lung injury: clinical features and diagnostic dilemmas

Transfusion-related acute lung injury (TRALI) is recognized as the number-one cause of transfusion-associated death in the United States. Although TRALI was not designated as the number-one cause until 2004, respiratory-related symptoms associated with blood transfusion have been reported for decades. More recently, our understanding of the pathophysiology and clinical significance of TRALI has advanced significantly, and great efforts are being implemented for patient safety. This article reviews the background, history, definitions, clinical features, and pathophysiology of TRALI. It also discusses some of the difficulties in diagnosing TRALI, compares some of the important components in the differential diagnosis, and describes some of the efforts being implemented for patient safety.

Comparison of usefulness of tissue Doppler imaging versus brain natriuretic peptide for differentiation of constrictive pericardial disease from restrictive cardiomyopathy

Brain (B-type) natriuretic peptide (BNP) and tissue Doppler imaging may distinguish restrictive cardiomyopathy (RCMP) from idiopathic constrictive pericardial disease (CP). However, their comparative efficacy is unknown for patients with CP from secondary causes (e.g., surgery or radiotherapy). We compared the efficacy of tissue Doppler imaging and BNP for differentiation of RCMP (n = 15) and CP (n = 16) were compared. BNP was higher in patients with RCMP than CP (p = 0.008), but the groups overlapped, particularly for BNP <400 pg/ml. BNP was lower with idiopathic CP than secondary CP (139 +/- 50 vs 293 +/- 69 pg/ml; p <0.001) or RCMP (139 +/- 50 vs 595 +/- 499 pg/ml; p <0.001), but not significantly different between those with secondary CP and RCMP (293 +/- 69 vs 595 +/- 499 pg/ml; p = 0.1). Patients with CP and RCMP had less overlap in early diastolic and isovolumic contraction tissue Doppler imaging velocities compared with BNP, with clear separation of groups evident with mean early diastolic annular velocities (averaged from 4 walls). Early diastolic tissue Doppler imaging velocity was superior to BNP for differentiation of CP and RCMP (area under the curve 0.97 vs 0.76, respectively; p = 0.01). In conclusion, mean early diastolic mitral annular velocity correctly distinguished CP from RCMP even when there was a large overlap of BNP between the 2 groups.

N-terminal pro-brain natriuretic peptide is a useful diagnostic marker for transfusion-associated circulatory overload

BACKGROUND

Transfusion-associated circulatory overload (TACO) can be difficult to diagnose and distinguish from transfusion-related acute lung injury (TRALI), but is a relatively common complication that occurs when increases in blood volume overwhelm the cardiovascular system. Brain natriuretic peptide (BNP) has been shown to be a functional marker for TACO. N-terminal pro-brain natriuretic peptide (NT-proBNP) is another marker that could be more helpful than BNP since it has a longer half-life in circulation and is also much more stable in laboratory samples. In this study, whether NT-proBNP is a useful diagnostic marker for TACO was evaluated.

STUDY DESIGN AND METHODS

Forty patients were enrolled into a case-control study (16 patients with TACO and 24 control patients) and had pre- and posttransfusion NT-proBNP concentrations evaluated from submitted type-and-screen blood samples.

RESULTS

The sensitivity of elevated posttransfusion NT-proBNP to diagnose TACO was 93.8 percent, the specificity was 83.8 percent, and the accuracy was 87.5 percent. Elevated posttransfusion NT-proBNP is the only independent variable for the diagnosis of TACO based on multivariate logistic regression.

CONCLUSION

NT-proBNP is both a sensitive and a specific marker for TACO and can be helpful in confirming transfusion associated fluid overload. This study also demonstrates that many patients who experience TACO may already be in a state of excess volume. Clinicians should be aware that many asymptomatic patients have excess fluid and transfusion may cause these patients to become symptomatic.