REDHOT

Rapid Emergency Department Heart Failure Outpatient Trial (REDHOT)



Rapid Emergency Department Heart Failure Outpatient Trial (REDHOT)

Congestive heart failure (CHF) is a major and increasing cause of death and disability worldwide. In the U.S. alone, the prevalence of heart failure is 4.6 million, with an incidence rate of 550,000 new cases a year and approximately 957,000 hospitalizations annually. The economic cost of CHF is estimated at $56 billion a year, 70% of which is due to hospitalization. One-third of patients with known CHF are admitted annually to the hospital, most of these through the emergency department (ED).

Between 75% to 90% of all patients presenting to the ED with presumed CHF are admitted to the hospital, leading to exorbitant costs and resource utilization . This high percentage of admissions is in part due to the absence of reliable clinical or laboratory criteria that could aid in the disposition decision. Although signs and symptoms of CHF may aid in the initial diagnosis of CHF, there is a poor relationship between symptoms of CHF and both the severity of cardiac dysfunction and prognosis.

B-type natriuretic peptide (BNP) levels have been used to successfully aid in the diagnosis of CHF in patients presenting with dyspnea. Because BNP levels correlate with both disease severity and prognosis they should be of value in assisting in the appropriate management and eventual disposition of CHF patients in the ED. The purpose of the study was to illustrate the relationships among BNP levels within the diagnostic range, clinical decision making, and outcomes. If the magnitude of BNP elevation above the traditional diagnostic threshold of 100 is prognostic, then it may be useful in deciding ultimate admission or discharge from the ED and other clinical judgments.

Methods

Study population

The study was approved by the institutional review boards of participating REDHOT study centers. The subject sample consists of a total of 464 patients at 10 sites who were enrolled from June 12, 2001 to February 3, 2003. Patients over the age of 18 years presenting to the ED with CHF and who received treatment in the ED or hospital admission for CHF were included. Current myocardial infarction (MI) or acute coronary syndrome with ST-segment deviation of =1 mm, renal failure requiring dialysis, or patients with a baseline BNP concentration of =100 pg/ml were excluded. Once written consent was obtained, a blood sample was collected for purposes of measuring the patient's BNP concentration.

The study coordinator ran these assays on-site at the point of care. Physicians were told only whether or not the patient met study criteria (BNP level >100 pg/ml).

After their initial clinical evaluation, physicians were asked to rate the severity of disease (New York Heart Association [NYHA] functional class I to IV) and whether or not they believed the patient would ultimately be admitted to the hospital (initial disposition).

The research assistant collected other data including elements from the present and past history, the physical examination, reports of other blood tests, interpretations of chest X-rays, and interpretations of other diagnostic ...