The use of brain natriuretic peptide as a screening test for left ventricular systolic dysfunction- cost-effectiveness in relation to open access echocardiography.

BACKGROUND: Heart failure due to left ventricular systolic dysfunction (LVSD) has a high prevalence in the adult population but is difficult to diagnose accurately on clinical grounds in the community. Early diagnosis is important as effective treatments are available to reduce morbidity and mortality. Echocardiography is widely used to assess heart failure; however, this technology is relatively expensive and of limited availability. A potential diagnostic aid in primary care is the measurement of plasma brain natriuretic peptide (BNP). OBJECTIVE: This study was performed to assess the value of BNP measurement as a selective pre-screen for breathless patients referred for open access echocardiography. METHODS: BNP was measured by radioimmunoassay with prior extraction in 83 breathless subjects (age range 37-87 years, mean 72). Standard echocardiography was performed and left ventricular systolic function was assessed. RESULTS: The prevalence of LVSD was 31% in this group. At cut-off values chosen to give negative predictive values for LVSD of >98% (BNP = 19 pg/ml), the sensitivity, specificity and positive predictive value for BNP were 100, 49.1 and 46.9%. Using this BNP threshold as a pre-screen for echocardiography would make a net saving of pound 964.20 without compromising the diagnostic accuracy. CONCLUSION: BNP measurement appears to have a significant cost-effective benefit for the selection of patients for echocardiography.