Final Diagnosis Of Heart Failure Research Articles

Value of inferior vena cava collapsibility index as marker of heart failure in chronic obstructive pulmonary disease exacerbation

IntroductionInferior vena cava (IVC) diameter variability with respiration measured by ultrasound was found to be useful for the diagnosis of heart failure (HF) in ED patients with acute dyspnea. Its value in identifying HF in acute exacerbation of chronic obstructive pulmonary disease exacerbation (AECOPD) was not specifically demonstrated.ObjectiveTo determine the value of ΔIVC in the diagnosis of HF patients with AECOPD.MethodsThis is a prospective study conducted in the ED of three Tunisian university hospitals including patients with AECOPD. During this period, 401 patients met the inclusion criteria. The final diagnosis of HF is based on the opinion of two emergency experts after consulting the data from clinical examination, cardiac echocardiography, and BNP level. The ΔIVC was calculated by two experienced emergency physicians who were blinded from the patient’s clinical and laboratory data. A cut off of 15% was used to define the presence (< 15%) or absence of HF (≥ 15%). Left ventricular ejection fraction (LVEF) was also measured. The area under the ROC curve, sensitivity, specificity, and positive and negative predictive values were calculated to determine the diagnostic and predictive accuracy of the ΔIVC in predicting HF.ResultsThe study population included 401 patients with AECOPD, mean age 67.2 years with male (68.9%) predominance. HF was diagnosed in 165 (41.1%) patients (HF group) and in 236 patients (58.9%) HF was excluded (non HF group). The assessment of the performance of the ΔIVC in the diagnosis of HF showed a sensitivity of 37.4% and a specificity of 89.7% using the threshold of 15%. The positive predictive value was 70.9% and the negative predictive value was 66.7%. The area under the ROC curve was 0.71(95%, CI 0.65–0.76). ΔIVC values were not different between HF patients with reduced LVEF and those with preserved LVEF.ConclusionOur results showed that ΔIVC has a good value for ruling out HF in ED patients consulting for AECOPD.

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

Diagnostic significance of NT-proBNP estimation in patients with acute dyspnea.

To determine the diagnostic significance of plasma NT-proBNP estimation in patients presenting with acute dyspnea in Emergency Department. An observational, cross sectional study. From January to June 2008 at Liaquat National Hospital, Karachi. In this study, 100 patients were selected with purposive non-probability sampling who had presented to the emergency department with acute dyspnea. Plasma NT-proBNP levels, chest X-ray and transthoracic echocardiography were performed at the time of admission. NT-proBNP levels were assessed by commercial tests. The clinical diagnosis of congestive heart failure, patient's hospital course and discharge diagnosis were cross-tabulated with NT-proBNP levels. The chi-square test for categorical data and Student's t-test for numerical data was applied at 0.05 level of significance to compare patients with and without heart failure (HF). Further comparative analysis between age groups was done by one way ANOVA test. The mean NT-proBNP level among the 79 subjects with a final diagnosis of heart failure was 10918 compared with 461 pg/ml in those without heart failure (p=0.001). The diagnostic accuracy of NT-proBNP at a cutoff of 300 pg/milliliter (ml) was 100 percent. An optimal strategy to identify acute HF was to use age-related cut-points of 450 and 900 pg/ml for ages < 50 and > 50 years, which yielded 100% sensitivity and 86% specificity for acute HF. An age-independent cut-point of 300 pg/ml had 100% negative predictive value to exclude acute HF. NT-proBNP is useful in establishing or excluding the diagnosis of congestive heart failure in patients with acute dyspnea.

Does B-Type Natriuretic Peptide Testing Affect Outcome and Management of Patients With Acute Dyspnea?

Letters18 August 2009Does B-Type Natriuretic Peptide Testing Affect Outcome and Management of Patients With Acute Dyspnea?Ajay Pachika, MD, Malek Numeir, MD, and Kiranmayi Adimoolam, MBBSAjay Pachika, MDFrom Crozer Chester Medical Center, Upland, PA 19013, and Siddhartha Medical College, Andhra Pradesh, India 520008.Search for more papers by this author, Malek Numeir, MDFrom Crozer Chester Medical Center, Upland, PA 19013, and Siddhartha Medical College, Andhra Pradesh, India 520008.Search for more papers by this author, and Kiranmayi Adimoolam, MBBSFrom Crozer Chester Medical Center, Upland, PA 19013, and Siddhartha Medical College, Andhra Pradesh, India 520008.Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/0003-4819-151-4-200908180-00020 SectionsAboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail TO THE EDITOR:Schneider and colleagues (1) reported on a well-conducted randomized trial on the impact of BNP testing on management of patients with dyspnea who present to the emergency department. They examined the impact of BNP measurement on clinical outcomes among patients with acute dyspnea. It is a well-powered study, given the large sample size.Schneider and colleagues noted that, within the BNP-tested group, patients with a final diagnosis of heart failure had markedly elevated BNP values compared with patients without heart failure and that BNP testing accurately discriminated between the groups. However, it is very important to know ...

Heart failure in people younger than 50 years is more common in black than white americans and is closely associated with poorly treated and controlled hypertension: the cardia study

HEART FAILURE IN PEOPLE YOUNGER THAN 50 YEARS IS MORE COMMON IN BLACK THAN WHITE AMERICANS AND IS CLOSELY ASSOCIATED WITH POORLY TREATED AND CONTROLLED HYPERTENSION: THE CARDIA STUDY Heart failure (HF) is a major public health issue that leads to substantial morbidity and mortality in the United States. Age, hypertension, and coronary ischemia are all well-documented risk factors for HF in older adults, but less is known about the incidence, risk factors, and demographics associated with HF in younger people. The Coronary Artery Risk Development in Young Adults (CARDIA) study, a 20-year multicenter longitudinal study of black and white men and women designed to investigate the development of coronary artery disease in young adults, offered an opportunity to explore these relationships. Beginning in 1985–1986, persons 18 to 30 years of age were enrolled from 4 American cities: Birmingham, Alabama; Chicago, Illinois; Minneapolis, Minnesota; and Oakland, California. The cohort was well balanced with respect to self-reported race (52% black) and sex (55% women). Multiple clinical measurements, including blood pressure (BP), were obtained at baseline and after 2, 5, 7, 10, 15, and 20 years. BP was measured in standardized fashion, with hypertension defined as a BP of at least 140 ⁄90 mm Hg or use of antihypertensive medications. During both their study examinations and in yearly telephone follow-up, participants were asked about overnight hospitalizations. For each hospitalization, records were obtained and adjudicated for the presence of incident HF, defined as a hospitalization where the final diagnosis of HF was made by a treating physician and HF was treated with at least a diuretic and either digitalis or an afterload-reducing agent. Death was also reported to the study centers every 6 months, and each death was adjudicated to determine whether it was due to HF. In year 5, as part of the examination, participants underwent echocardiography. Systolic function was considered abnormal if the ejection fraction (EF) was either <40% or qualitatively described as abnormal; systolic function was considered borderline if the EF was 40% to 60%. Left ventricular hypertrophy (LVH) was defined as a left ventricular mass index at least 51 g ⁄m. Using multiple statistical tools, the CARDIA investigators compared baseline and subsequent development of risk factors in participants in whom HF did and did not develop. The CARDIA study enrolled 5115 individuals with a mean age of 25 years and a mean baseline BP around 110 ⁄70 mm Hg. The retention rate in the study was exceptionally high, with 87.5% of the original cohort completing the yearly telephone interview at year 20 and 71.8% completing the year 20 in-person examination. During the 20 years of follow-up, incident HF occurred in 27 patients (0.5%), which was more common than the incidence of myocardial infarction. Twenty-six of the 27 patients who developed incident HF were black. The cumulative incidence of HF was 1.1% in black women and 0.9% in black men, compared with 0.08% in white women and 0% in white men. From the Division of General Internal Medicine ⁄ Division of Cardiology, University of Nevada School of Medicine; Risk Reduction Center, Saint Mary’s Regional Medical Center, Reno, NV; Primary Care Service Line, Ralph H. Johnson VA Medical Center; and Division of General Internal Medicine ⁄Geriatrics, Medical University of South Carolina, Charleston, SC Address for correspondence: Michael J. Bloch, MD, Risk Reduction Center, Saint Mary’s Regional Medical Center, 645 North Arlington Street, Suite 460, Reno, NV 89503 E-mail: mbloch@aol.com

Accuracy of chest radiographs in the emergency diagnosis of heart failure

The purpose of this study was to determine the diagnostic accuracy of chest radiographic findings of heart failure (HF) in current patients presenting with dyspnea in the emergency department. In a secondary analysis of the BASEL study, initial chest radiographs of 277 patients with acute dyspnea were evaluated by two radiologists blinded to the adjudicated diagnosis (56% had the final diagnosis of HF). Predefined radiographic criteria of HF were used. Statistical analysis included receiver-operating characteristic (ROC) analysis and calculation of a logistic regression model including B-type natriuretic peptide (BNP) levels. The reader's overall impression showed the highest area under the ROC curve for the diagnosis of HF in both supine and erect patient positions (0.855 and 0.857). Among individual radiographic findings, peribronchial cuffing in the supine position (0.829) showed the highest accuracies. The lowest accuracy was found for the vascular pedicle width in the supine position (0.461). Logistic regression analysis showed no significant differences between the reader's overall impression, the radiographic model, and BNP testing. In our study, the combination of radiographic features provided valuable information and was of comparable accuracy as BNP-testing for the diagnosis of HF.

Interrater reliability of hemodynamic profiling of patients with heart failure in the ED

Objective Hemodynamic profiling (HP) of patients with heart failure (HF) based on clinical assessment of central congestion and peripheral perfusion has been widely used by cardiologists to help guide therapy and determine prognosis but has never been tested or validated in the emergency department (ED). We hypothesized that the interrater reliability of HP in the ED would be good or greater than 0.6. Methods Study design. This was a prospective, observational study. Setting. It was conducted in an academic suburban ED with emergency medicine residency. Subjects. A convenience sample of patients presenting to the ED with suspected acute decompensated HF was enrolled. Measures. Demographic and clinical information was collected using standardized data collection forms. Two emergency medicine physicians (masked to each other) evaluated all patients and classified them into 1 of 4 hemodynamic categories based on the presence or absence of central congestion (wet or dry) and peripheral hypoperfusion (cold or warm): warm and dry, warm and wet, cold and dry, and cold and wet. B-type natriuretic peptide levels, objective test of cardiac function, and final cardiologist diagnoses were obtained. Data analysis. Interrater reliabilities for overall hemodynamic profile and individual elements of congestion and perfusion were calculated using κ coefficients. Results Sixty-eight patients were enrolled. Their mean age was 72 ± 14 years, 53% were female, and 78% were white. Of the patients, 79% had a final diagnosis of HF. Most patients (>60%) were considered wet and warm. Interrater agreement for HP was 64%, κ = 0.28 (95% confidence interval, 0.01-0.51). Interrater agreement was poor to fair for all elements of congestion and perfusion except peripheral edema ( κ = 0.67) and a narrow pulse pressure ( κ = 0.66). Conclusions Hemodynamic profiling of patients with HF by emergency physicians in the ED is not highly reliable. One in 5 patients thought to have HF in the ED did not have a final diagnosis of HF.

N-Terminal Pro–B-Type Natriuretic Peptide Testing Improves the Management of Patients With Suspected Acute Heart Failure

The diagnostic utility of N-terminal pro-B-type natriuretic peptide (NT-proBNP) in heart failure has been documented. However, most of the data were derived from countries with high healthcare resource use, and randomized evidence for utility of NT-proBNP was lacking. We tested the hypothesis that NT-proBNP testing improves the management of patients presenting with dyspnea to emergency departments in Canada by prospectively comparing the clinical and economic impact of a randomized management strategy either guided by NT-proBNP results or without knowledge of NT-proBNP concentrations. Five hundred patients presenting with dyspnea to 7 emergency departments were studied. The median NT-proBNP level among the 230 subjects with a final diagnosis of heart failure was 3697 compared with 212 pg/mL in those without heart failure (P<0.00001). Knowledge of NT-proBNP results reduced the duration of ED visit by 21% (6.3 to 5.6 hours; P=0.031), the number of patients rehospitalized over 60 days by 35% (51 to 33; P=0.046), and direct medical costs of all ED visits, hospitalizations, and subsequent outpatient services (US $6129 to US $5180 per patient; P=0.023) over 60 days from enrollment. Adding NT-proBNP to clinical judgment enhanced the accuracy of a diagnosis; the area under the receiver-operating characteristic curve increased from 0.83 to 0.90 (P<0.00001). In a universal health coverage system mandating judicious use of healthcare resources, inclusion of NT-proBNP testing improves the management of patients presenting to emergency departments with dyspnea through improved diagnosis, cost savings, and improvement in selected outcomes.

Association of atrial fibrillation and amino-terminal pro–brain natriuretic peptide concentrations in dyspneic subjects with and without acute heart failure: Results from the ProBNP Investigation of Dyspnea in the Emergency Department (PRIDE) study

Amino-terminal pro-brain natriuretic peptide (NT-proBNP) testing is useful for diagnosis or exclusion of heart failure (HF) in dyspneic patients. Atrial fibrillation (AF) may cause dyspnea in the absence of acute HF and may also affect plasma levels of NT-proBNP. We prospectively enrolled 599 patients presenting with dyspnea to the emergency department and obtained a blood sample for NT-proBNP measurement. The diagnosis of AF was identified via presentation electrocardiogram. A final diagnosis of HF was determined by blinded study physicians using all available hospital records for each subject through 60 days of follow-up. We assessed the association between the presence of AF and level of NT-proBNP in subsets of patients with and without HF. Of 599 dyspneic patients, 75 (13%) were in AF at presentation; these patients had significantly higher median NT-proBNP levels when compared with those without AF (2934 vs 294 pg/mL, P < .0001). Among patients with acute HF, AF was present in 28%; NT-proBNP levels were lower in those with AF versus those without (3488 vs 4492 pg/mL, P < .001), but AF was not independently associated with NT-proBNP after multivariable adjustment. In patients without acute HF, median NT-proBNP concentrations were significantly higher in those with AF than in those without (932 vs 121 pg/mL, P = .02); in these subjects, AF was the strongest predictor of an NT-proBNP concentration in a range consistent with acute HF (odds ratio 9.94, 95% CI 2.97-33.3, P < .001). Atrial fibrillation is associated with higher NT-proBNP concentrations in dyspneic patients, particularly in those without acute HF.

Utilidad del NTproBNP en el manejo urgente del paciente con disnea severa y diagnóstico dudoso de insuficiencia cardíaca

Measurement of N-terminal pro-B-type natriuretic peptide (NTproBNP) helps in diagnosing heart failure (HF). The test's usefulness may be greatest in patients with severe dyspnea of uncertain origin. However, NTproBNP has not been evaluated specifically in this setting. This prospective emergency department study included 70 patients with shortness of breath at rest as their chief complaint. In the attending physician's opinion, both HF and a non-cardiac cause were equally probable. Blinded NTproBNP measurement was carried out in blood samples collected on admission. Patients were monitored and their final diagnoses were based on clinical findings, therapeutic responses, and cardiac and noncardiac tests performed during hospitalization. The NTproBNP level was higher in the 49 patients (70%) with a final diagnosis of HF (P = .006); the area under the ROC curve was 0.72 (0.60-0.82). The optimum diagnostic cut-off value was 900 pg/mL, which had an accuracy of 87%, a sensitivity of 98%, and a negative predictive value of 92%. The NTproBNP level was significantly higher in the 6 patients (9%) who died during hospitalization (P = .009); the area under the ROC curve was 0.87 (0.76-0.93) and the optimum cut-off value for predicting death was 5500 pg/mL, which had an accuracy of 77%, a sensitivity of 100%, and a positive likelihood ratio of 4.2. In patients with severe dyspnea and an uncertain diagnosis of HF, an NTproBNP level < 900 pg/mL helps exclude the presence of HF, whereas a NTproBNP level > 5500 pg/mL identifies patients at an increased risk of death.

Usefulness of NTproBNP in the Emergency Management of Patients With Severe Dyspnea and an Uncertain Heart Failure Diagnosis

Measurement of N-terminal pro-B-type natriuretic peptide (NTproBNP) helps in diagnosing heart failure (HF). The test's usefulness may be greatest in patients with severe dyspnea of uncertain origin. However, NTproBNP has not been evaluated specifically in this setting.This prospective emergency department study included 70 patients with shortness of breath at rest as their chief complaint. In the attending physician's opinion, both HF and a non-cardiac cause were equally probable. Blinded NTproBNP measurement was carried out in blood samples collected on admission. Patients were monitored and their final diagnoses were based on clinical findings, therapeutic responses, and cardiac and noncardiac tests performed during hospitalization.The NTproBNP level was higher in the 49 patients (70%) with a final diagnosis of HF (P = .006); the area under the ROC curve was 0.72 (0.60-0.82). The optimum diagnostic cut-off value was 900 pg/mL, which had an accuracy of 87%, a sensitivity of 98%, and a negative predictive value of 92%. The NTproBNP level was significantly higher in the 6 patients (9%) who died during hospitalization (P = .009); the area under the ROC curve was 0.87 (0.76-0.93) and the optimum cut-off value for predicting death was 5500 pg/mL, which had an accuracy of 77%, a sensitivity of 100%, and a positive likelihood ratio of 4.2.In patients with severe dyspnea and an uncertain diagnosis of HF, an NTproBNP level < 900 pg/mL helps exclude the presence of HF, whereas a NTproBNP level > 5500 pg/mL identifies patients at an increased risk of death.

Diagnosing heart failure in aortic valve stenosis.

In aortic valve stenosis (AS), heart failure (HF) omens a high risk of death and is an indication for prompt valve replacement. We studied whether its detection can be facilitated by measuring plasma N-terminal B-type natriuretic peptide (Nt-BNP) or by estimating pulmonary capillary wedge pressure (PCWP) using echocardiography. A cross-sectional cohort study in a university hospital. We studied 137 consecutive adult patients referred to our unit for invasive evaluation of isolated AS. All patients underwent cardiac catheterization, measurement of plasma Nt-BNP and estimation of PCWP by Doppler echocardiography of transmitral and pulmonary venous flow velocities. The final diagnosis of HF was based on the combined criteria of dyspnoea on ordinary effort and PCWP >14 mmHg at cardiac catheterization. The performance of Nt-BNP and the PCWP estimate in the detection of HF were studied using receiver operating characteristic (ROC) analysis. Totally 42 patients had HF. A cardiologist's clinical diagnosis of HF had high specificity (94%) but poor sensitivity (66%). With an optimized cut-off point, plasma Nt-BNP had moderate sensitivity (77%) and specificity (79%) for HF; the ROC area was 0.83. The echocardiographic PCWP estimate classified 90% of patients correctly as having normal or truly elevated (>14 mmHg) PCWP. Its sensitivity and specificity for the diagnosis of HF were 80 and 95% respectively; the ROC area was 0.88. With a cut-off point of 12 mmHg, the sensitivity of the PCWP estimate was 85% and specificity, 88%. The recognition of HF in patients with AS can be improved by estimating PCWP using Doppler echocardiography of transmitral and pulmonary venous flow velocities.

B-type natriuretic peptide and renal function in patients with decompensated heart failure

Background: It has been described that renal function may influence B-type nautriuretic peptide levels. Objectives: We sought to describe the relationship between renal function and BNP level in patients (pts) presenting to the emergency department (ED) with decompensated heart failure (HF). Methods: From April 2001 through August 2003, 260 pts presented to an ED complaining of dyspnea and were included in a study evaluating the role of BNP in the diagnosis and prognosis of HF. Two hundred and fifty two (96.9%) of these pts had both BNP levels and baseline estimated creatinine clearance (CC) and were included in this analysis. Mean age was 72±26 years, and 125 (49.6%) were male. One hundred and twenty one (48%) pts had a final diagnosis of HF as the cause of dyspnea. According to CC the pts were classified into 3 categories: category 1 (n=42), CC>90 ml/min; category 2 (n=78), CC 60-90 ml/min; and category 3 (n=132), CC<60 ml/min. Pts with CC less than 15 ml/min and those on dialysis therapy were excluded. Results: There was a weak correlation between CC and BNP levels, with Pearson correlation index of – 0.23 for pts with HF and – 0.25 for pts without HF (p<0.001 in both groups). Mean BNP levels in categories 1,2 and 3, were 748 pg/mL, 984 pg/mL and 1,236 pg/mL in pts with HF and 95 pg/mL, 138 pg/mL and 246 pg/mL in pts without HF. Optimum cut points for BNP were 100 pg/mL (area under the receiver operating characteristic curve [AUC]=0.96), 160 pg/mL (AUC=0.94) and 240 pg/mL (AUC=0.95) for categories 1 to 3, respectively. Conclusion: BNP was useful in the diagnosis of HF in all categories of CC. However, the optimal cut points were influenced by renal function.

Obesity influences B-type natriuretic peptide levels in patients with decompensated heart failure

Background: It has been described that adipose cells express the clearance receptor for natriuretic peptides. Therefore, obesity may be responsible, at least in part, for low natriuretic peptide activity observed in some patients with heart failure (HF). Objectives: We sought to describe the relationship between obesity and B-type natriuretic peptide (BNP) levels in patients who present to the emergency department with HF. Methods: From April 2001 through August 2003, 260 patients presented to an emergency department complaining of dyspnea and were included in a study which assessed the utility of BNP measurement using a point of care assay in the diagnosis and prognosis of HF. Among these patients, 124 (48%) had a final diagnosis of HF as the cause of dyspnea and were included in this analysis. Mean age was 72±28 years and 61 (49.2%) were male. All patients were NYHA class III or IV. We assessed the relationship between body mass index (BMI) and BNP values, controlling for confounding factors. According to BNP levels, the patients were classified into three categories: less than 500 pg/mL, 500 to 1,000 pg/mL, and above 1,000 pg/mL. Results: Mean BMI was 28.3±4.6 Kg/m2 and 42 (34%) were obese (IMC>30 Kg/m2). Despite similar age, NYHA class, left ventricle ejection fraction, and serum creatinine, BNP levels were significantly lower in obese patients as compared to non-obese (806±212 vs 1,126±320 pg/mL, p<0.0001). Independent predictors of lower BNP levels (< 500 pg/mL) were age<70 years, (p=0.0002), creatinine<1.3 mg/dL (p=0.0034) and IMC>30 Kg/m2 (p=0.0042). Conclusion: This study suggests that obesity influences BNP levels in patients with decompensated HF.

Brain natriuretic peptide and n-terminal brain natriuretic peptide in the diagnosis of heart failure in patients with acute shortness of breath

ObjectivesThis study sought to compare the utility of measurement of plasma brain natriuretic peptide (BNP) and N-terminal brain natriuretic peptide (N-BNP) in the diagnosis of heart failure (HF) in patients with acute dyspnea. BackgroundPlasma BNP is useful in differentiating HF from other causes of dyspnea in the emergency department. The N-terminal component of BNP has a longer half-life, and in HF increases in plasma N-BNP are proportionately greater. MethodsWe studied 205 patients (average age 70 ± 14 years) presenting to the emergency department with acute dyspnea. Brain natriuretic peptide was analyzed using a point-of-care test and two locally developed radioimmunoassays. N-terminal BNP was measured using a locally developed radioimmunoassay and a commercially available assay. Final diagnosis of HF was adjudicated by two cardiologists. ResultsPatients with HF (n = 70) had higher mean levels of both hormones by all assays (p < 0.001 for all). Results with all assays correlated closely (r values between 0.902 and 0.969). Subjects with left ventricular (LV) dysfunction or left-sided valvular disease but no HF had intermediate levels of BNP and N-BNP (lower than subjects with HF, and higher than subjects without HF with no LV dysfunction or left-sided valvular disease) (p < 0.01 for all). Using optimum cut-offs, specificity for the diagnosis of HF ranged between 70% and 89% (highest for the N-BNP assays). Sensitivity ranged between 80% and 94% (highest for the point-of-care BNP assay). ConclusionsMeasurement of BNP or N-BNP is useful in the diagnosis of HF in acute dyspnea. Commercially available assays compare favorably with well-validated laboratory assays. Differences in sensitivity and specificity may influence the assay choice in this setting.