Page 151 - Biomarkers for risk stratification and guidance in heart failure

Chapter 7
dyspnea at the ED, ranging from 34% to 58% of dyspneic patients6,7. Many risk scores have been developed for diseases that might cause dyspnea like heart failure,8 acute coronary syndromes,9 atrial fibrillation3, pulmonary embolism,10 exacerbation of COPD11 and pneumonia.12 Proposed risk scores for emergency department dyspnea were developed for long-term risk stratification,13,14 however, a general risk score for short-term prognosis in dyspneic patients was still lacking. Because the evaluation of dyspneic patients in the ED is difficult15 and dyspnea can be caused by both harmless as well as highly lethal conditions, 16 an accurate non-diagnosis-specific short-term mortality risk score is expected to be helpful in clinical practice. This notion is strengthened by our finding that there was a relatively high admission rate in the low-risk category (44%) and high discharge rate in the high-risk category (24%) with similar mortality rates between admitted and discharged patients. Thus, knowledge of individual risk might help the treating physician at the ED to decide on urge of intervention, admission and timing of re- evaluation. However, in contrast to the widely implemented CHA2DS2-Vasc and HAS-BLED risk scores, the MARKED-Risk score is currently not used in general practice. Main reason is the lack of therapeutic consequences: if knowledge of individual risk leads to improvement of prognosis still remains to be assessed in future trials.
Biomarkers in HF and dyspnea
In 2008, Braunwald17 classified circulating biomarkers related to HF into seven categories based on their pathophysiological effects in the disease and hypothesized that multiple biomarkers in combination would provide a valuable means for risk stratification (figure 1). Biomarkers used in our multi marker study encompassed five of these seven categories: Myocardial stretch (NT-proBNP), myocyte injury (hs-cTnT), Matrix remodeling / fibrosis (Gal-3), inflammation (hs-CRP / Gal-3) and renal dysfunction (Cys-C). Recently many potential biomarkers for HF have been investigated for risk stratification in acute HF. The natriuretic peptide NT-proBNP characterizes cardiac wall stress and is an established biomarker for diagnosis and prognosis of acute HF.18 However the prognostic value of NT-proBNP is limited for short-term risk stratification in acute heart failure (AHF) compared with other biomarkers.19,20
Galectin-3, a marker that is linked to fibrosis and inflammation is involved in heart failure, cancer and renal disease and is predictive for all-cause mortality in the general population.21 Although its diagnostic role in HF is of limited value20,
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