B-type Natriuretic Peptide Testing Research Articles

B-Type Natriuretic Peptide-A Paradox in the Diagnosis of Acute Heart Failure with Preserved Ejection Fraction in Obese Patients.

B-type natriuretic peptide (BNP) represents a clinical tool for the diagnosis and prognostic evaluation of acute and chronic heart failure patients. The purpose of this retrospective study was to evaluate BNP values in obese and non-obese patients with acute heart failure with preserved ejection fraction. In this study, we enrolled 240 patients who presented to the emergency department complaining of acute shortness of breath and fatigue. The patients were divided into two groups according to their body mass index (BMI) values. The BMI was calculated as weight (kilograms) divided by height (square meters). The BNP testing was carried out in the emergency department. Group I included patients with a BMI of <30 kg/m2 and group II included patients with a BMI of ≥30 kg/m2. The average age of the patients was 60.05 ± 5.02 years. The patients in group II were significantly younger compared with those included in group I. Group II included a higher number of women compared to group I. Group I had fewer patients classified within New York Heart Association (NYHA) functional classes III and IV compared with group II. Echocardiography revealed an ejection fraction of ≥50% in all participants. Lower BNP levels were observed in patients from group II (median = 56, IQR = 53-67) in comparison to group I (median = 108.5, IQR = 106-112) (p < 0.001). Obesity and heart failure are continuously rising worldwide. In this retrospective study, we have highlighted the necessity to lower the threshold of BNP levels in obese patients with acute heart failure and preserved ejection fraction.

External validation of survival predicting score in repaired tetralogy of Fallot: an opportunity to improve

Abstract Introduction In recent years, integrating both better diagnosis and treatment allowed most adults with repaired tetralogy of Fallot (rTOF) to expect a longer life expectancy. However, a minority is at higher risk for premature cardiovascular death. Recently, 2 scores identified the subgroup of rTOF patients (pts) who are at high annual risk of death and ventricular arrhytmias (VA). We aimed to implement both in our population. Methods Retrospective single center review was done on rTOF pts who undergone cardiovascular magnetic resonance with gadolinium, blood sampling for B-type natriuretic peptide (BNP), echocardiography and cardiopulmonary exercise testing. The risk scores were calculated with weighted independent predictors, namely presence of late gadolinium enhancement in left ventricle (LV) and right ventricle (RV), akinetic RV outflow length, LV and RV ejection fraction (EF), RV systolic pressure, peak oxygen uptake (pVO2), BNP, atrial arrythmias and age. Low mortality risk was defined as 0-20 points, intermediate as 21-50 and high ≥51. In terms of VA prediction, low risk was defined as 0-20 points, intermediate as 21-39 and high as ≥51. Results From a total of 240 rTOF pts, 61 (56% male, mean age 34±9 years) had all the necessary data. RV dysfunction was present in 52.5%, RV systolic pressure was high in 12 and LVEF≤35% in 18% pts. BNP level was elevated in 27 and pVO2≤17mL/kg/m2 in 14.8% pts. The mean mortality risk score was 15.1±11.2, being that 68.9% had a lower and 31.1% an intermediate risk. Regarding VA score, the mean was 14.7±10.8, where the majority (80.3%) were in lower risk. 29.5% had a sustain atrial arrhythmia (mainly atrial fibrillation) and 14.8% a VA. There were 3 cardiac related deaths (4.9%). Analysis of time to event data showed that mortality and VA scores were not predictors of overall mortality (M) or VA events, respectively. However, considering 1-year M, LVEF≤35% (p= 0.002), RVEF≤35% (p=0.002), pVO2≤17mL/kg/m2 (p&amp;lt;0.001), and both scores: M (p=0.013) and VA (p&amp;lt;0.001) were predictors of that endpoint. In multivariate analysis, VA risk score (p=0.035) and low pVO2 (p= 0.006) were independent 1-year M predictors. Conclusion In our population, ventricular arrhythmia score and low peak oxygen uptake were independent predictors of 1-year mortality. However, there is probably a selection bias. Since the scores were recently proposed, patients were not recruited prospectively, many ended up not having all the needed or recent data, thus were not included. There is the need to validate and improve available scores to truly assess the risk of mortality and arrhythmias, as well as defined protocols and longer follow-up for this purpose.

THU357 A Case Of Recurrent Insulin-induced Edema In A Pediatric Adolescent Patient

Abstract Disclosure: G.J. Mora Calderon: None. R.L. Aguirre: None. D. Preston: None. Introduction: Insulin induced edema is a very rare complication seen after initiation of insulin therapy or after escalation of previous insulin regimen in patients with diabetes. The exact incidence of this condition is unknown. Insulin induced edema seems to have a female predominance and is associated primarily with patients who are underweight. The severity of insulin induced edema can range from mild localized peripheral edema to more severe and generalized complications, including cardiac failure and serosal effusions. There is a higher risk for severe complications in older patients with pre-existing cardiac, hepatic, or renal conditions. Usually, the course is benign and self-resolved without any intervention. Severe and prolonged cases have been reported to need adjuvant therapy (e.g diuretics or sympathomimetic agents) or sodium-restricted dietary regimens. Increasing blood glucose target with a decreased insulin regimen has been proposed as a possible option to prevent insulin induced edema. We present a 14 year-old-male patient with history of poor controlled type 1 diabetes mellitus and recurrent insulin-induced edema after strengthening of his insulin therapy. Case Presentation: A 14-year-old male with poorly controlled type 1 diabetes mellitus presented to the emergency with pitting edema of his face and hands that started a week after intensification of his insulin regimen. His weight increased from 73 kg to 84 kg in about 10 days. His vital signs at presentation were stable and besides the pitting edema, the rest of the physical examination was unremarkable. His mother reported a previous episode of edema that occurred approximately a year before this presentation and about a month after he was first diagnosed with diabetes mellitus. His most recent HbA1c was 14.4%. Patient was admitted for evaluation. Electrocardiogram, transthoracic echocardiogram, chest x-ray, and multiple laboratories (including a comprehensive metabolic panel, complete blood count, B-type natriuretic peptide, urine microalbumin, and thyroid function test ) came back all normal. The edema slowly improved and was eventually discharged. No adjuvant therapy was needed during his hospitalization. Conclusion: The diagnosis of insulin induced edema is primarily based on the exclusion of other etiologies. Most cases reported only one episode after initiation of insulin therapy or after escalation of previous insulin regimen, but it can happen multiple times as noted in our patient. Presentation: Thursday, June 15, 2023

ACCESS TO HEART FAILURE SERVICES IN CANADA: FINDINGS OF THE HEART & STROKE NATIONAL HEART FAILURE RESOURCES AND SERVICES INVENTORY.

The rising incidence of Heart Failure (HF) in Canada necessitates commensurate resources dedicated to its management. Several health system partners launched a HF Action Plan to understand the current state of HF care in Canada and address inequities in access and resources. A national Heart Failure Resources and Services Inventory (HF-RaSI) was conducted between 2020-2021 of all 629 acute care hospitals and 20 urgent care centres in Canada. The HF-RaSI consisted of 44 questions on available resources, services and processes across acute care hospitals and related ambulatory settings. HF-RaSIs was completed by 501 acute care hospitals and urgent care centers, representing 94.7% of all HF hospitalizations across Canada. Only 12.2% of HF care was provided by hospitals with HF expertise and resources, and 50.9% of HF admissions were in centers with minimal outpatient or inpatient HF capabilities. Across all Canadian hospitals, 28.7% did not have access to brain natriuretic peptide testing, and only 48.1% had access to on-site echocardiography. Designated HF medical directors were present in 108 sites (21.6%), and 81 sites (16.2%) had dedicated inpatient interdisciplinary HF teams. There were 141 HF clinics (28.1% of all sites); of these, 57 (40.4%) had average wait times from referral to first appointment of > 2 weeks. Significant gaps and geographic variation in delivery and access to HF services exist in Canada. This study highlights the need for provincial and national health systems changes and quality improvement initiatives to ensure equitable access to the appropriate evidence-based HF care.

Evidence for Anchoring Bias During Physician Decision-Making

Cognitive biases are hypothesized to influence physician decision-making, but large-scale evidence consistent with their influence is limited. One such bias is anchoring bias, or the focus on a single-often initial-piece of information when making clinical decisions without sufficiently adjusting to later information. To examine whether physicians were less likely to test patients with congestive heart failure (CHF) presenting to the emergency department (ED) with shortness of breath (SOB) for pulmonary embolism (PE) when the patient visit reason section, documented in triage before physicians see the patient, mentioned CHF. In this cross-sectional study of 2011 to 2018 national Veterans Affairs data, patients with CHF presenting with SOB in Veterans Affairs EDs were included in the analysis. Analyses were performed from July 2019 to January 2023. The patient visit reason section, documented in triage before physicians see the patient, mentions CHF. The main outcomes were testing for PE (D-dimer, computed tomography scan of the chest with contrast, ventilation/perfusion scan, lower-extremity ultrasonography), time to PE testing (among those tested for PE), B-type natriuretic peptide (BNP) testing, acute PE diagnosed in the ED, and acute PE ultimately diagnosed (within 30 days of ED visit). The present sample included 108 019 patients (mean [SD] age, 71.9 [10.8] years; 2.5% female) with CHF presenting with SOB, 4.1% of whom had mention of CHF in the patient visit reason section of the triage documentation. Overall, 13.2% of patients received PE testing, on average within 76 minutes, 71.4% received BNP testing, 0.23% were diagnosed with acute PE in the ED, and 1.1% were ultimately diagnosed with acute PE. In adjusted analyses, mention of CHF was associated with a 4.6 percentage point (pp) reduction (95% CI, -5.7 to -3.5 pp) in PE testing, 15.5 more minutes (95% CI, 5.7-25.3 minutes) to PE testing, and 6.9 pp (95% CI, 4.3-9.4 pp) more BNP testing. Mention of CHF was associated with a 0.15 pp lower (95% CI, -0.23 to -0.08 pp) likelihood of PE diagnosis in the ED, although no significant association between the mention of CHF and ultimately diagnosed PE was observed (0.06 pp difference; 95% CI, -0.23 to 0.36 pp). In this cross-sectional study among patients with CHF presenting with SOB, physicians were less likely to test for PE when the patient visit reason that was documented before they saw the patient mentioned CHF. Physicians may anchor on such initial information in decision-making, which in this case was associated with delayed workup and diagnosis of PE.

Significant discordance between point of care BNP values obtained by the i-STAT and the Beckman DXI 800, causing confusion in patient management when both methods are used interchangeably by clinicians

B-type natriuretic peptide (BNP) is used as a biomarker of heart failure. In our hospital point of care (POCT) BNP test is performed in EDTA whole blood using i-STAT (Abbott Laboratories, Abbott Park, IL, USA) and in the clinical laboratory using EDTA plasma and the DXI 800 analyzer (Beckman, Brea, CA, USA). We compared BNP values in 88 patients obtained by using the i-STAT followed by using the DXI 800. The time difference between the two analyses varied from 32 min to less than 12 h. In addition, 11 specimens were simultaneously analyzed for BNP using both the i-STAT and the DXI 800 analyzer. Plotting BNP concentrations obtained by the DXI 800 in the x-axis (reference method) and the i-STAT values in the y-axis, we observed the following regression equation; y = 1.4758 x + 23.452 (n = 88, r = 0.96), indicating significant positive bias with the i-STAT. In addition, we also observed significant differences between BNP values obtained by the i-STAT and the DXI 800 in 11 specimens analyzed simultaneously. Therefore, clinicians should not use BNP concentrations obtained by the i-STAT interchangeably with BNP concentrations obtained by the DXI 800 analyzer for patient management.

Availability of B-type natriuretic peptide testing in Brazilian public health system

Availability of B-type natriuretic peptide testing in Brazilian public health system

Diagnostic value of atrial natriuretic peptide (ANP), B-type natriuretic peptide (BNP) and their correlation with lipoproteins in dogs with myxomatous mitral valve disease

BackgroundMyxomatous mitral valve disease (MMVD) is the most common diagnosed cardiovascular disease in dogs. Atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) tests are used to diagnose congestive heart failure, but there are conflicting reports about their value in diagnosing the subclinical stages of MMVD in dogs. Moreover, the diagnostic value of blood lipoproteins in dogs with MMVD is still unclear. The purpose of this study was to assess the serum concentrations of ANP, BNP and lipoproteins of dogs with MMVD and to evaluate the correlation of the levels of ANP and BNP with lipoproteins.ResultsThis study was performed on 24 dogs with MMVD and 10 healthy dogs. Dogs with MMVD were classified in to stages B1 (n = 11), B2 (n = 6), C (n = 4) and D (n = 3) groups according to the classification suggested by American College of Veterinary Internal Medicine guidelines. Our results showed that the mean serum BNP levels were significantly increased for all MMVD groups compared to control dogs. The mean serum ANP levels for the stage B2, C and D groups were significantly higher than the control group, while the mean serum ANP concentrations did not differ significantly between the stage B1 and control groups. An increase in BNP level was observed in 87.5% of patients. Although BNP concentrations were elevated in 100% of dogs with stages C, D and B2, high BNP was observed in 72.72% of dogs with stage B1. Regarding ANP, 58.33% of patients had an increase in ANP. However, elevated ANP levels were found in only 27.27% of patients in stage B1, while increased ANP levels were observed in 66.66 and 100% of patients in stage B2 and C/D groups respectively. Also, in all patients with MMVD, the mean serum concentrations of high-density lipoprotein cholesterol (HDL-C) were approximately 1.7 to 2 times significantly lower than the control group. Additionally, the mean serum low-density lipoprotein cholesterol (LDL-C) increased significantly (1.9-2.7 times) compared to the control group.There was a significant inverse correlation between HDL-C and BNP, and HDL-C and ANP. LDL-C showed a significant positive correlation with BNP, and ANP. Also, LDL-C, but not HDL-C, had a significant positive correlation with LA/AO ratio, LVIDd, LVIDdN and VHS. BNP and ANP showed a significant positive correlation with LA/AO, LVIDd, LVIDdN and VHS.ConclusionsSerum BNP has a greater diagnostic value than serum ANP in dogs with MMVD. In addition, serum BNP can be used to determine the subclinical stages of B1 and B2 MMVD. This study also suggests that dogs with subclinical MMVD, showed an increase in BNP along with a decrease in HDL-C and an increase in LDL-C, which are known to be risk factors for cardiovascular diseases in human. However, it seems that high LDL-C is more involved in the pathogenesis of MMVD than low HDL-C. Therefore, periodic testing of serum lipoproteins is recommended in high-risk patients, even if total cholesterol levels are normal.

Angina Pektoris Hastalarında B-Tipi Natriüretik Peptit ve Kalsiyum Skoru

Objective: The purpose of this study is to look into the relationship between coronary artery disease evaluated with multislice computed tomography (MSCT) findings and B-type natriuretic peptide (BNP) and calcium score (CaS). Material and Method: The study included 83 patients who were administered to our center and who had asymptomatic and stable angina pectoris. Blood samples were collected for BNP testing, and the Abbott AxSYM System kit was used for measurements. Calcium scoring was performed on each of the four main coronary arteries, and the total “Agatston” score was calculated for each patient by summing up the results. MSCT angiograms were studied at the three-dimensional operating base. Results: Coronary artery disease (CAD) was found in 51 (61.4%) patients, while the coronary arteries of 32 (38.6%) patients were deemed normal. Single-vessel involvement was detected in 17 (20.5%) patients, two-vessel involvement in 18 (21.7%) patients, and three-vessel involvement in 16 (19.3%) patients. While patients with CAD had a median BNP of 33.9 (0–834), those without CAD had a median of 19.2 (0–185), which was statistically significant (p=0.011). Furthermore, there was a positive correlation between the number of vessels involved and BNP (r = 0.364, p=0.001). BNP levels were found to be significantly higher in hypertensive patients (p=0.008). The CaS and BNP median of the group with three-vessel involvement were significantly higher (p &amp;lt; 0.001 and p=0.007, respectively). Conclusion: As a result, high CaS and BNP levels were discovered to be a marker for the presence and severity of CAD.

Delta NT-proBNP predicts cardiotoxicity in HER2-positive breast cancer patients treated with trastuzumab

Background Overall survival has improved significantly in patients with human epidermal growth receptor 2 (HER2)-positive breast cancer due to the use of the monoclonal antibody trastuzumab blocking HER2. However, patients may develop trastuzumab-induced cardiotoxicity (TIC) leading to congestive heart failure. Here we assessed whether analysing NT-proBNP and assessment of electrocardiography (ECG) could detect TIC during trastuzumab therapy. Methods One hundred thirty-six patients undergoing adjuvant, neoadjuvant or palliative chemotherapy and HER2 blockade for HER2-positive breast cancer were prospectively assessed with echocardiography, ECG and N-terminal – pro hormone B-type natriuretic peptide (NT-proBNP) testing at baseline and at 6 and 12 months of trastuzumab therapy. TIC was defined as a left ventricular ejection fraction (LVEF) of less than 50% and a decline from baseline of ≥10 units. Results Six patients developed TIC under 12 months of trastuzumab therapy (incidence 4.4%). NT-proBNP increased from 198.8 ± 64.0 pg/ml to 678.7 ± 132.4 pg/ml (p < .05) in TIC patients. With a cut-off point of 276.5 pg/ml for NTproBNP and increase in NT-proBNP by 75.8 pg/ml from baseline the sensitivity was 100% and the specificity 95% to detect TIC. Compared with controls, TIC patients were older (68.3 ± 1.1 years and 56.2 ± 1.4 years, respectively; p < .01), had more often diabetes mellitus (OR = 63.5, 95% CI: 5.63–915, p < .01) and atrial fibrillation (OR = 12.3; 95% CI: 1.89–74.62; p < .05) and had lower baseline LVEF (57.1 ± 1.4% and 61.4 ± 0.3%, respectively; p < .001). Abnormal ECGs were common in patients developing TIC. Conclusions Measuring changes in NTproBNP may be used to monitor patients for TIC under trastuzumab therapy. Patients with a cardiovascular risk profile are more at risk of developing TIC.

Value of systolic time intervals in the diagnosis of heart failure in emergency department patients with undifferentiated dyspnea.

The diagnosis of heart failure in the emergency department (ED) is challenging. The aim of this study was to evaluate systolic time intervals (STIs) using phonoelectrocardiography for the diagnosis of heart failure (HF) in ED patients with undifferentiated dyspnea. A total of 855 patients with dyspnea and suspected HF were prospectively enrolled. They underwent echocardiographic measurements of left ventricular ejection fraction (LVEF), B-type natriuretic peptide (BNP) testing and computerised phonoelectrocardiography to assess STIs including electromechanical activation time (EMAT), left ventricular ejection time (LVET) and EMAT/LVET ratio. Diagnosis accuracy of STIs was calculated including sensitivity, specificity, likelihood ratio and receiver operating characteristic (ROC) curve. Patients with HF (n=530) had significantly higher EMAT and lower LVET compared with non-HF patients. ROC curve c-statistic was 0.74, 0.72 and 0.78 for EMAT, LVET and EMAT/LVET respectively. Sensitivity and specificity of EMAT/LVET at a cut-off=40% were 72% and 88% respectively. EMAT/LVET had the highest correlation with LVEF (r=0.48). In patients with intermediate BNP (n=107), positive likelihood ratio increased from 1.8 with BNP alone to 3.6 with BNP combined to EMAT/LVET. Patients without HF had STIs values not significantly different from those with preserved LVEF (≥45%). Given their immediate availability, phonoelectrocardiography STIs' parameters and particularly EMAT/LVET ratio could have an important role in the diagnosis approach of HF in patients with undifferentiated dyspnea in the ED.

Heart Failure Integrated Care Project: overcoming barriers encountered by primary health care providers in heart failure management.

Objective Heart failure (HF) is associated with increased morbidity and mortality. A significant proportion of HF patients will have repeated hospital presentations. Effective integration between general practice and existing HF management programs may address some of the challenges in optimising care for this complex patient population. The Heart Failure Integrated Care Project (HFICP) investigated the barriers encountered by primary healthcare providers in providing care to patients with HF in the community. Methods Five general practices in the St George and Sutherland regions (NSW, Australia) that employed practice nurses (PNs) were enrolled in the project. Participants responded to a printed survey that asked about their perceived role in the management of HF patients and their current knowledge and confidence in managing this condition. Participants also took part in a focus group meeting and were asked to identify barriers to improving HF patient management in general practice, and to offer suggestions about how the project could assist them to overcome those barriers. Results Barriers to effective delivery of HF management in general practice included clinical factors (consultation time limitations, underutilisation of patient management systems, identifying patients with HF, lack of patient self-care materials), professional factors (suboptimal hospital discharge summary letters, underutilisation of PNs), organisation factors (difficulties in communication with hospital staff, lack of education regarding HF management) and system issues (no Medicare rebate for B-type natriuretic peptide testing, insufficient Medicare rebate for using PN in chronic disease management). Conclusions The HFICP identified several barriers to improving integrated management for HF patients in the Australian setting. These findings provide important insights into how an HF integrated care model can be implemented to strengthen the working relationship between hospitals and primary care providers in delivering better care to HF patients. What is known about the topic? Multidisciplinary HF programs are heterogeneous in their structures, they have low patient participation rates and a significant proportion of HF patients have further presentations to hospital with HF. Integrating the care of HF patients into the primary care system following hospital admission remains challenging. What does this paper add? This paper identified several factors that hinder the effective delivery of care by primary care providers to patients with HF. What are the implications for practitioners? The findings provide important insights into how an HF integrated care model can be implemented to strengthen the working relationship between tertiary health facilities and primary care providers in delivering better care to HF patients.

Use of the Clinical Examination in the Diagnosis of Cardiac Syncope.

Patient history: Age at first syncopal episode older than 35 years = 3.3 History of atrial fibrillation or flutter = 7.3 Known severe structural heart disease = 3.3 to 4.8 Dyspnea prior to syncope = 3.5 Chest pain/angina prior to syncope = 3.4 to 3.8 Cyanotic during syncope = 6.2 Diagnostic tests: High-sensitivity cardiac troponin T > 42 pg/mL = 5.1 High-sensitivity cardiac troponin I > 31.3 pg/mL = 5.4 NT-proBNP ≥ 210.5 pg/mL = 47 NT-proBNP > 1966 pg/mL = 5.8 BNP > 302 pg/mL = 6.3 Multivariable evaluation: Heart disease, abnormal ECG, or both = 2.3 EGSYS score 3 or more = 2.8 to 3.3 Vasovagal score less than −2 = 1.7 to 8.6 Patient history: Age at first syncopal episode 35 years or younger = 0.13 Diagnostic tests: Normal cardiac troponin T or I = 0.15 to 0.39 Normal BNP level = 0.16 to 0.21 Multivariable evaluation: EGSYS score less than 3 = 0.12–0.17 Absence of heart disease, abnormal ECG or both = 0.20 Vasovagal score −2 or more = 0.10–0.84 Syncope or transient loss of consciousness is a common problem seen in the emergency department (ED), accounting for 1% to 1.5% of ED visits annually.1 Cardiac syncope caused by cerebral hypoperfusion secondary to cardiopulmonary events such as arrhythmia or structural heart disease, accounts for 5% to 21% of syncope events.2 Cardiac syncope is associated with an increased risk of premature death and cardiac events.3, 4 It is therefore important for emergency providers to differentiate cardiac syncope from other causes. This systematic review by Albassam et al.5 evaluated patient characteristics, physical examination findings, and diagnostic tests to identify cardiac causes of syncope. The authors searched the MEDLINE, Embase, CINAHL, and Cochrane databases, selecting 11 studies that met inclusion and exclusion criteria. Each study included at least 10 subjects aged 12 years or older, for a total of 4,317 patients. Studies were assigned levels of evidence developed for the Rational Clinical Examination series.6 Several historical factors were associated with an increased likelihood of cardiac syncope including age at first syncopal episode 35 years or older; history of atrial fibrillation or flutter; known severe structural heart disease; dyspnea or chest pain prior to syncope; and witnessed cyanosis during syncope. An elevated cardiac troponin T or I and an elevated B-type natriuretic peptide (BNP) both modestly increased the probability of cardiac syncope. Factors that decreased the probability included age less than 35 years at first syncopal episode; normal cardiac troponin T or I; and normal BNP. Combinations of findings such as Evaluation of Guidelines in Syncope Study (EGSYS) score ≥ 3; vasovagal score < −2; and abnormal electrocardiogram, heart disease, or both were more useful when absent than when present. The results of this review should be interpreted cautiously. Included studies generally defined cardiac syncope based on cardiologist judgment. Five of 11 studies included specialty referral populations or inpatients, leading to the potential for spectrum bias. Applying these results to a general ED population might lead to additional testing or interventions in patients who have lower risk of cardiac syncope than the studied population. Misclassification may have further skewed the results as patients with unexplained syncope were excluded from several studies. Many of the clinical findings resulted from single studies. Studies often included a wide age range of patients despite the incidence of syncope, related ED visits, and serious outcomes increasing sharply after the age of 60.7 Cardiac biomarkers such as troponin or BNP testing appear to be an attractive diagnostic option, however, they did not rule in or rule out cardiac syncope. Moreover, these cardiac biomarkers were likely used to diagnose cardiac syncope leading to incorporation bias. ACEP clinical policy, appreciating these limitations, suggests a risk stratification approach focusing on patient history and physical examination to avoid unnecessary testing and hospital admissions.1 In summary, the accurate diagnosis of cardiac syncope is helpful in determining an appropriate plan of care. While no single variable can independently diagnose or exclude cardiac syncope, several clinical findings may be used cohesively to help guide health care providers.

P1641What is the best BNP cutoff value to rule out or rule in the diagnosis of heart failure in the community?

Abstract Background There is no consensus on the cutoff value of B-type natriuretic peptide (BNP) to rule in or rule out the diagnosis of heart failure (HF) in the community. For instance, the ESC guidelines propose a cutoff of 35 pg/mL and the Canadian Guidelines propose 50 pg/mL. Objectives To evaluate the performance of several BNP cutoffs to rule in or rule out the diagnosis of HF in the community. Methods A total of 633 randomly selected individuals, aged 45 to 99 years, of both sexes, enrolled in a primary care program in several regions of a medium-sized city with 487,562 inhabitants were evaluated. A cross-sectional study, in which one-day clinical data collection, laboratory tests, BNP tests and tissue Doppler echocardiogram (TDE) were performed. The final diagnosis of HF was adjudicated by two independent cardiologists. Sensitivity (SEN), specificity (SPE), negative predictive value (NPV) and positive predictive value (PPV) were evaluated for different BNP cutoffs. A ROC curve was used to determine the best cutoff value. Results The mean age was 59.6±10.4 years and 62% were women. The incidence for ACC/AHA HF stages Zero, A, B, C and D were, respectively, 11.8%, 36.3%, 42.6%, 9.3% and 0%. There was a predominance of HF with preserved versus reduced ejection fraction (59% vs 41%). For the identification of the 59 patients with symptomatic HF, the cutoff of 35pg/mL presented SEN 98%, SPE 87%, NPV 100% and PPV 44%. For cutoff of 50pg/mL these values were SEN 78%, SPE 94%, NPV 98% and PPV 58%. The best combination of SEN and SPE was with a cutoff of 42pg/mL (SEN 92% and SPE 91%). Only one patient with HF had BNP&lt;35pg/mL. With the cutoff of 50pg/mL, 13 (22%) of the 59 pts with symptomatic HF would not have been diagnosed. Conclusions The cutoff with higher specificity to rule in the diagnosis of HF was 50pg/mL. However, with this cutoff an expressive number of patients with HF would have been missed. For screening purpose in the community, the best cutoff to rule out HF was 35pg/mL, as proposed in the ESC guidelines

Role of BNP vs NT-proBNP Testing in the Age of New Drug Therapies: Sacubitril-Valsartan

Sacubitril-valsartan (Entresto), a new dual drug therapy that includes an angiotensin receptor neprilysin (NEP)15 inhibitor (sacubitril), is directed at reducing the risk of cardiovascular death and hospitalization for heart failure (HF) in patients with chronic HF (New York Heart Association classes II–IV) and reduced ejection fraction (HFrEF). Since its approval for the treatment of HFrEF, a commonly raised question has been whether treatment with this drug can complicate the interpretation of B-type natriuretic peptide (BNP) testing results compared to those of the N-terminal proBNP assay because Entresto may interfere with BNP clearance. The clinical and analytical studies addressing this issue are limited. Furthermore, the diversity of both BNP and NT-proBNP assays used in clinical laboratory practice have not been adequately evaluated in clinical trials, and studies to provide an evidence-based conclusion regarding the appropriate assays to use when a patient is on Entresto are lacking. In this article, 5 experts from the US and Europe provide their views regarding this issue. Do you think the differences between BNP and NT-proBNP measurements in patients receiving Entresto are only an early phenomenon because they both seem to be reduced over time? James Januzzi: In the PARADIGM-HF trial, NT-proBNP fell acutely after initiation of Entresto and then continued to drop over time until the end of the trial. Both the enalapril and Entresto arms had a slow, gradual drop in NT-proBNP by the end of trial. This drop likely reflects one of 2 possibilities. First, it may be the subtraction of noncompleters by the end of trial led to a perceived further drop in NT-proBNP (sicker patients that withdrew or died who likely had higher NT-proBNP concentrations). Alternatively, longer treatment with either therapy (angiotensin-converting enzyme inhibitor or angiotensin receptor neprilysin inhibitors) led to further stability, resulting in less synthesis and release of …

Analytical performance of a single epitope B-type natriuretic peptide sandwich immunoassay on the Minicare platform for point-of-care diagnostics

Point-of-care B-type natriuretic peptide (BNP) testing with adequate analytical performance has the potential to improve patient flow and provide primary care givers with easy-to-use advanced diagnostic tools in the management of heart failure. We present the analytical evaluation of the Minicare BNP immunoassay under development on the Minicare I-20 platform for point-of-care testing. Analytical performance was evaluated using EDTA venous whole blood, EDTA plasma and capillary whole blood. Method comparison with a lab-testing system was performed using samples from 187 patients. Normal values were determined based on 160 healthy adults, aging from 19 to 70 years. Limit of blank (LoB), limit of detection (LoD) were determined to be 3.3 ng/L, 5.8 ng/L. Limit of quantitation (LoQ) in whole blood at 20% and 10% coefficient of variation (CV) was found < 9 ng/L and <30 ng/L respectively without significant differences between EDTA whole blood and EDTA plasma. Total CV was found to be from 6.7% to 9.7% for BNP concentrations between 92.6 and 3984 ng/L. The sample type comparison study demonstrated correlation coefficients between 0.97 and 0.99 with slopes between 1.03 and 1.09 between the different samples. Method comparison between Minicare BNP and Siemens ADVIA Centaur BNP demonstrated a correlation coefficient of 0.92 with a slope of 1.06. The 97.5% URL of a healthy population was calculated to be 72.6 ng/L. The Minicare BNP assay is a robust, easy-to-use and sensitive test for rapid determination of BNP concentrations that can be used in a near-patient setting.

The Role of GDF-15 in Heart Failure Patients With Chronic Kidney Disease

BackgroundGrowth differentiation factor-15 (GDF-15) is a stress-inducible cytokine and member of the transforming growth factor-β cytokine superfamily that refines prognostic assessment in subgroups of patients with heart failure (HF). We evaluated its role in HF patients with chronic kidney disease (CKD, estimated glomerular filtration rate <60 mL/min/1.73 m2). MethodsA total of 358 patients with stable systolic HF were followed for a median of 1121 (interquartile range, 379-2600) days. Comprehensive evaluation including B-type natriuretic peptide (BNP) and GDF-15 testing was performed at study entry; the analysis was stratified according to kidney function. ResultsPatients with CKD (33.8%) were older, had more often diabetes, and were less often treated with angiotensin converting enzyme inhibitors (ACEi)/angiotensin receptor blockers (ARB). GDF-15 was associated with estimated glomerular filtration rate, whereas BNP was associated with left ventricular-end diastolic diameter and ejection fraction (P < 0.01). During follow-up, 244 patients (68.2%) experienced an adverse outcome (death, urgent transplantation, implantation of mechanical circulatory support). In patients with HF and CKD, the Cox proportional hazard model identified BNP, GDF-15, sex, systolic blood pressure, sodium, total cholesterol, and ACEi/ARB treatment as significant variables associated with an adverse outcome (P < 0.05). In multivariable analysis, BNP was replaced by GDF-15. Net reclassification improvement confirmed prognostic superiority of the model encompassing GDF-15 (GDF-15, sodium, total cholesterol, ACEi/ARB treatment) compared with the model without GDF-15 (BNP, sex, sodium, ACEi/ARB treatment), net reclassification improvement 0.62, P = 0.005. In contrast, in patients with HF and normal kidney function, BNP remained superior to GDF-15 in a multivariable model. ConclusionsIn patients with systolic HF and CKD, GDF-15 is more strongly associated with adverse outcomes than the conventionally used BNP.

Real-world presentation with heart failure in primary care: do patients selected to follow diagnostic and management guidelines have better outcomes?

ObjectiveTo describe associations between initial management of people presenting with heart failure (HF) symptoms in primary care, including compliance with the recommendations of the National Institute for Health and Care...

Diagnosing heart failure with NT-proBNP point-of-care testing: lower costs and better outcomes. A decision analytic study.

BackgroundAfflicting 1–2% of the adult population, heart failure (HF) is a condition with considerable morbidity and mortality. While echocardiography may be considered the gold standard diagnostic test, GPs have relied on symptoms and clinical findings in diagnosing the condition.AimThe aim of this study was to estimate 1-year health outcome and costs of three diagnostic strategies: 1) history and clinical findings ('clinical diagnosis'); 2) clinical diagnosis supplemented with NTproBNP point-of-care test ('POC test') in the GP’s surgery; or (3) in hospital laboratory ('hospital test').Design & settingA decision tree model was developed to simulate 1-year patient courses with each strategy in Norway.MethodSensitivity and specificity of clinical diagnosis (56% and 68%), and of N-terminal pro B-type natriuretic peptide test ([NT-proBNP] 90% and 65%), were based on published literature. The probabilities of referral to hospital were based on a survey of Norwegian GPs (n = 103). The costs were based on various Norwegian fee schedules. Sensitivity analyses were conducted to examine the uncertainty of the results.ResultsThe 1-year per person societal costs were €543, €505, and €607 for clinical diagnosis, POC test, and hospital test, respectively. Even though POC entails higher laboratory costs, the total primary care costs were lower because of fewer re-visits with the GP and less use of spirometry. While 38% of patients had a delayed diagnosis with clinical diagnosis, the proportions were 22% with both POC test and hospital test. Results were most sensitive to the probability of use of spirometry.ConclusionPOC testing results in earlier diagnosis and lower costs than the other diagnostic modalities.

What Role Should B-Type Natriuretic Peptide Play in Predicting Late Graft Dysfunction Following Cardiac Transplantation?

Introduction: B-type natriuretic peptide (BNP) levels are a marker of left ventricular dysfunction and a powerful predictor of morbidity and mortality in patients with chronic heart failure. There have been limited reports indicating that BNP levels tend to be higher around the time of late graft dysfunction (LGD) following cardiac transplantation.1Bader F.M. Rogers R.K. Kfoury A.G. Gilbert E.M. Horne B.D. Stehlik J. et al.Time-dependent changes in B-type natriuretic peptide after heart transplantation: correlation with allograft rejection and function.Congest Heart Fail. 2009; 15: 63-67Crossref PubMed Scopus (11) Google Scholar, 2Martínez-Dolz L. Almenar L. Hervás I. Moro J. Agüero J. Sánchez-Lázaro I. et al.Prognostic relationship between two serial determinations of B-type natriuretic peptide and medium-long-term events in heart transplantation.JHLT. 2008; 27: 735-740Abstract Full Text Full Text PDF PubMed Scopus (8) Google Scholar, 3Damodaran A. Dardas T. Wu A.H. Dyke D.B. Hummel S.L. Cowger J.A. et al.Changes in serial B-type natriuretic peptide level independently predict cardiac allograft rejection.JHLT. 2012; 31: 708-714Abstract Full Text Full Text PDF PubMed Scopus (15) Google Scholar Objective: To assess the utility of serial BNP testing as a predictive indicator for LGD. Methods: We retrospectively reviewed heart transplantations performed at our center between 2012 and 2015, and compared the time course of BNP levels in the group of patients with LGD (defined as ejection fraction ≤50% and/or cardiac index <2) to that in the group without LGD. The predictive ability of BNP testing at different time points was assessed by receiver-operator characteristic (ROC) analysis. Multivariate logistic regression was used to assess the association between BNP and LGD. Results: Of 203 patients included, 73 (36%) patients (median age 60 years [50, 65]; 67% male) developed LGD. In both groups the average BNP was elevated at time of transplant and then decreased over time (P < .001). Throughout follow-up, BNP was greater in the LGD group than in the non-LGD group (Fig. 1A; with significant differences in the first 3 months and after 1 year; P < .05). ROC analysis showed that BNP at the time of LGD was more strongly associated with LGD than BNP at transplantation (Fig. 1B). The LGD group exhibited greater rates of biopsy-proven rejection (P < .0001) and poorer 1-year survival (P < .001). Multivariate analysis revealed that BNP at time of LGD (P < .0001) and ≥2R rejection (P = .043) were both associated with LGD status. Conclusions: These data showed elevated BNP levels surrounding the time of documented LGD after cardiac transplantation. Thus, our results add to the current literature supporting serial BNP testing as a prognostic tool for the occurrence of LGD in this patient population. Prospective studies are needed to validate these findings.