Screening for left ventricular systolic dysfunction: the use of B-type natriuretic peptide

Congestive heart failure (CHF) is a disease condition that is increasing in prevalence and is associated with significant morbidity and mortality. Left ventricular systolic dysfunction (LVSD) is a treatable precursor of CHF, but remains asymptomatic in about half of the individuals afflicted. This observation has spurred interest in screening for LVSD. Plasma B-type natriuretic peptide (BNP) is a widely accepted test for the diagnosis of overt CHF. In this review, we examine the potential role for plasma BNP as a screening tool for asymptomatic LVSD. The performance of any screening test depends on its accuracy, the prevalence of the disease condition screened for, and the availability of resources for follow-up of individuals in whom the disease was detected. In the context of community-wide screening for LVSD, a test with high specificity would be important so as to minimize the costs of expensive definitive follow-up tests (i.e. echocardiography). The prevalence of significant LVSD (ejection fraction 20.40) is low, limiting the enthusiasm for a screening program targeting the general population. This is especially true for women, in whom the condition is rare, and the performance characteristics of plasma BNP are sub-optimal. In men, plasma BNP may be a useful screening test in high-risk individuals in whom there are no other clinical indications for echocardiography. The choice of the appropriate plasma BNP threshold that triggers further work-up in such high-risk individuals may vary according to the availability of resources, and with the healthcare priorities of a community.