Clinical utility of natriuretic peptides in dialysis patients

Dialysis patients suffer a greatly heightened risk of cardiovascular morbidity and mortality. These patients also experience an extremely high prevalence of left ventricular hypertrophy, heart failure, and coronary artery disease. Thus, there is a clinical need to identify circulating biomarkers that have diagnostic value for cardiovascular disease and have prognostic importance so to facilitate earlier and more aggressive intervention. The natriuretic peptides, namely brain natriuretic peptide (BNP) or N-terminal pro-brain natriuretic peptide (NT-pro-BNP), belong to a family of vasopeptide hormones that are released from the heart and play a major role in blood pressure regulation and volume homeostasis through their direct effects on the kidney and systemic vasculature and represent a favorable aspect of neurohumoral activation. Testing for BNP or NT-pro-BNP has recently emerged as important diagnostic tool for heart failure and a useful biomarker for risk stratification in the general population. In dialysis patients, there has been interest in evaluating the potential of BNP and NT-pro-BNP as markers of volume status as they are frequently elevated in dialysis patients. However, the interpretation of their levels is confounded by impaired renal clearance and preexisting LV abnormalities which have limited their applicability as a surrogate marker of volume status. In this article, we discuss the pathophysiology accounting for the elevation of natriuretic peptides in dialysis patients and review current evidence that supports their clinical utility as a diagnostic and prognostic tool in this population.