Clinical Investigation
Congestive Heart Failure
Gray zone BNP levels in heart failure patients in the emergency department: Results from the Rapid Emergency Department Heart Failure Outpatient Trial (REDHOT) multicenter study

https://doi.org/10.1016/j.ahj.2005.10.017Get rights and content

Objectives

The study purpose was to examine “gray zone” B-type natriuretic peptide (BNP) levels (100-500 pg/mL) in terms of associated clinical factors, perceived severity, and outcomes in patients with established congestive heart failure (CHF).

Background

Although gray zone BNP levels may have diagnostic ambiguity, the implications of these levels in patients with an established diagnosis of CHF have not been examined.

Methods

REDHOT was a national prospective study in which 464 patients seen in the emergency department with dyspnea had BNP levels drawn. Entrance criteria included a BNP >100 pg/mL; however, physicians were blinded to the actual BNP level. Patients were followed up for 90 days.

Results

Thirty-three percent had gray zone BNP levels. There was no difference in perceived New York Heart Association class (P = .32) or admission rates (P = .76) between the gray zone and non–gray zone groups; 62% of patients with a gray zone BNP were identified as class III or IV CHF. Despite this perceived severity, the 90-day event rate was lower in the gray zone group (19.2% vs 32.9%, respectively, P = .002). Although patients in the gray zone had more symptoms of concomitant pulmonary disease, multivariate analysis could not demonstrate any variable that worsened the prognosis of patients with a gray zone BNP level.

Conclusions

In patients with established CHF, those with gray zone BNP levels have a better prognosis than those with non–gray zone levels despite being perceived by physicians as having New York Heart Association class III or IV CHF.

Section snippets

Study population

The REDHOT was a national, 10-center, prospective study. The study design and main results of the REDHOT study have been published elsewhere.17 Study investigators and centers are as listed in the authors' affiliation data (Appendix). The appropriate review boards at each participating institution approved the study. The study sample consisted of a total of 464 patients who were enrolled from June 12, 2001, to February 3, 2003. Patients who presented to the ED with CHF and who received

Results

The baseline characteristics of the study group of 464 patients are described in Table I. Patients were divided into those with a gray zone BNP (n = 154) and those with a non–gray zone BNP level (n = 310). Gray zone BNP patients accounted for 33% of the study group. The distribution of men and women differed significantly between the 2 groups with a higher portion of women having gray zone BNP levels than men (P < .001). In addition, gray zone BNP patients were found to have a higher body mass

Discussion

CHF is a major cause of death and disability worldwide resulting in considerable economic costs. Historically, a lack of objective tools available to help triage and prognosticate forced the clinician to rely on subjective evaluation of the patient's symptoms to determine diagnosis and treatment plan, including need for admission. The Breathing Not Properly study was the first large-scale, multinational, prospective study to irrefutably show that BNP could objectively establish or exclude the

References (27)

  • A. Maisel et al.

    Primary Results of the Rapid Emergency Department Heart Failure Outpatient Trial (REDHOT). A multicenter study of B-type natriuretic peptide levels, emergency department decision-making, and outcomes in patients presenting with shortness of breath

    J Am Coll Cardiol

    (2004)
  • A. Maisel et al.

    Bedside B-type natriuretic peptide in the emergency diagnosis of heart failure with reduced or preserved ejection fraction: results from the Breathing Not Properly Multinational Study

    J Am Coll Cardiol

    (2003)
  • S.J. Wieczorek et al.

    A rapid B-type natriuretic peptide assay accurately diagnoses left ventricular dysfunction and heart failure: a multicenter evaluation

    Am Heart J

    (2002)

    • Cited by (43)

    • Cardiac biomarkers of heart failure in chronic kidney disease

      2020, Clinica Chimica Acta

    • Interpreting the Wide Range of NT-proBNP Concentrations in Clinical Decision Making

      2018, Journal of the American College of Cardiology

    • Usefulness of natriuretic peptide testing and Doppler echocardiography at bedside in the diagnosis of acute heart failure

      2016, Annales de Cardiologie et d'Angeiologie

    • The abnormal status of uncarboxylated matrix Gla protein species represents an additional mortality risk in heart failure patients with vascular disease

      2016, International Journal of Cardiology
      Citation Excerpt :

      Conventional risk factors were dichotomized by usual cut-off points (see relevant section of tables). Usual cut-off point > 100 ng/L was used for definition of “elevated” BNP, while BNP ≥ 500 ng/L as lower limit of overt heart failure [19,20]. For functional classification of patients we used standard New York Heart Association (NYHA) criteria [21].

    • Mid-regional pro-atrial natriuretic peptide levels in the elderly: Clinical and prognostic implications, and comparison to B-type natriuretic peptides

      2013, Clinica Chimica Acta

    • Brain Natriuretic Peptide. Chronic Heart Failure and More?

      2012, Hospital Medicine Clinics
      Citation Excerpt :

      Although monitoring serial BNP levels has been associated with more guideline-based therapy, the evidence is mixed as to whether such a treatment plan improves clinical events more than traditional clinical assessment.17–20 There is growing evidence to support the use of serial measurements of BNP in both acute heart failure and CHF management.13–16 However, the variability in individual patients, laboratory findings, and clinical studies (no decrease in mortality or hospitalization in several large studies)21,22 creates reason to pause and to not endorse such practice yet.3,7,9

    View all citing articles on Scopus

    At the time of the study, Drs Maisel, McCullough, Hollander, Nowak, and Jesse served as consultants and received research support.

    Biosite Inc, San Diego, CA, provided all the Triage BNP devices and meters along with financial support.

    View full text
    Copyright © 2006 Mosby, Inc. All rights reserved.