Osteopontin predicts clinical outcome in patients after treatment of severe aortic stenosis with transcatheter aortic valve implantation (TAVI)

OBJECTIVE: Osteopontin (OPN) is an extracellular matrix protein that plays an integral role in myocardial remodelling and has previously been shown to be a valuable biomarker in cardiovascular disease. Because of the concentric myocardial hypertrophy associated with severe, symptomatic aortic stenosis (AS), we hypothesised that OPN expression may have a prognostic value in patients undergoing transcatheter aortic valve implantation (TAVI). METHODS: We prospectively included 217 patients undergoing TAVI between February 2011 and December 2013 with a median follow-up of 349 days. Twenty healthy individuals from the same age range free from structural heart disease served as controls. The primary endpoint for the analysis was survival time. RESULTS: Median preprocedural OPN levels (675 ng/mL; IQR 488.5-990.5 ng/mL) were significantly higher in patients with severe aortic valve stenosis compared with healthy controls (386 ng/mL; IQR 324.5-458, p<0.001). Patients with increased OPN values showed at baseline a decreased 6 min walk test performance, increased rates of atrial arrhythmia, and an increased risk of death during follow-up (HR 2.2; 95% CI 1.3 to 3.5 for the comparison of the highest vs lowest OPN quartile). Multiple Cox regression analysis demonstrated that OPN improves the prediction of an adverse prognosis further than N-terminal probrain natriuretic peptide. CONCLUSIONS: OPN levels at baseline are associated with adverse outcomes in patients with severe, symptomatic AS undergoing TAVI.