High-sensitivity troponin T in asymptomatic severe aortic stenosis

Background: In asymptomatic severe aortic stenosis (ASAS), treatment decisions are made on an individual basis, and case management presents a clinical conundrum. Methods: We prospectively phenotyped consecutive patients with ASAS using echocardiography, exercise echocardiography, cardiac MRI and biomarkers (NT-proBNP, high-sensitivity troponin T (hs-TnT) and ST2) (n = 58). The primary endpoint was a composite of cardiovascular death, new-onset symptoms, cardiac hospitalization, guideline-driven indication for valve replacement and cardiovascular death at 12 months. Results: During the first year, 46.6% patients met primary endpoint. In multivariable analysis, aortic regurgitation ≥2 (p = 0.01) and hs-TnT (p = 0.007) were the only independent predictors of the primary endpoint. The best cutoff value was identified as hs-TnT >10ng/L, which was associated with a ∼10-fold greater risk of the primary endpoint (HR, 9.62; 95% CI, 2.27-40.8; p = 0.002). A baseline predictive model including age, sex and variables showing p < 0.10 in univariable analyses showed an area under the curve (AUC) of 0.79(0.66-0.91). Incorporation of hs-TnT into this model increased the AUC to 0.90(0.81-0.98) (p = 0.03). Patient reclassification with the model including hs-TnT yielded an NRI of 1.28(0.46-1.78), corresponding to 43% adequately reclassified patients. Conclusions: In patients with ASAS, hs-TnT >10ng/L was associated with high risk of events within 12 months. Including hs-TnT in routine ASAS management markedly improved prediction metrics.