[Biomarkers for the evaluation of valvular aortic stenosis]

Aortic valve diseases, namely aortic stenosis (AS) and aortic regurgitation (AR), are common in developed countries with AS being the most common valvular heart disease. Symptomatic status and echocardiography are the most important clinical parameters to confirm the diagnosis, to assess the severity and to monitor progression of AS. Aortic valve replacement (AVR) is indicated in symptomatic patients with severe AS, but in asymptomatic patients with severe AS there is an ongoing controversial discussion whether these patients should undergo AVR or should be treated conservatively. For patients with moderate AS, surgical treatment is generally not recommended, even though recent data suggest that the outcome of these patients is worse than commonly assumed.In several studies that included patients with valvular AS, an elevation of BNP and NT-proBNP serum concentrations related to disease severity has been reported (Figure 1). Consequently, in a longitudinal study it was found, that NT-proBNP concentrations decrease after successful surgical therapy but increase in conservatively treated patients with AS (Figure 2). These changes of NT-proBNP values over time were related to changes of the transvalvular pressure gradient (Figure 3). Furthermore, it has been demonstrated in clinical outcome studies that elevated NT-proBNP and BNP values, respectively, were associated with an unfavorable clinical course especially in patients who were treated conservatively (Figure 4).Thus, these results suggest that natriuretic peptides can be used as biomarkers for the diagnostic work-up of patients with AS and might be helpful to decide on the optimal timing of AVR (Table 1).