Cardiac Biomarkers in End-Stage Renal Disease

Patients with end-stage renal disease (ESRD) often suffer from cardiovascular complications and comorbidities. For example, 55% of ESRD patients suffer from congestive heart failure (CHF) and cardiovascular diseases account for the majority of deaths among ESRD patients (Herzog, Ma, & Collins, 1998; National Institutes of Health; National Institute of Diabetes and Digestive and Kidney Diseases; Bethesda, 2007). It is, therefore, of great importance to diagnose the underlying cardiac pathologies and to provide accurate risk stratification in ESRD patients. Over the years, a number of accurate and sensitive biochemical markers have been introduced that have greatly advanced the diagnosis and risk stratification of cardiovascular diseases. The most prominent of these biochemical markers are the cardiac troponins (cTn, either T or I) and the brain natriuretic peptides (BNPs) and their use has revolutionized the diagnosis and risk stratification of acute coronary syndromes (ACS) and CHF respectively (A. S. Maisel et al., 2002; Thygesen, Alpert, & White, 2007). However, in the setting of ESRD, cardiac troponin concentrations can be elevated in the absence of apparent cardiac damage or clinical symptoms (Apple, Murakami, Pearce, & Herzog, 2004; Aviles et al., 2002; C. deFilippi et al., 2003; Havekes et al., 2006; Sommerer, Beimler, et al., 2007). Similarly, BNP and N-terminal proBNP (NT-proBNP) concentrations are virtually always increased in ESRD patients (Apple et al., 2004; Madsen et al., 2007). The presence of such continuously elevated cardiac troponin, BNP and NT-proBNP concentrations can interfere with their diagnostic and prognostic potential in ESRD patients (David et al., 2008; Pimenta et al., 2009; Wu et al., 2007). In this chapter, we will elaborate on the frequency of these cardiac biomarker elevations and discuss the underlying mechanisms behind them. In addition, we discuss the diagnostic and prognostic impact of these elevations and present approaches to improve the usefulness of cTn, BNP and NT-proBNP measurements.