ST2 predicts survival in patients undergoing transcatheter aortic valve implantation

To assess soluble suppression of tumorigenicity 2 (sST2) serum concentrations and predict mortality in patients undergoing transcatheter aortic valve implantation (TAVI).

We prospectively enrolled 74 patients with severe aortic stenosis (AS) who underwent TAVI and matched them to patients without aortic valve disease (n=74). AS patients underwent comprehensive echocardiographic and cardiac magnetic resonance imaging and laboratory examinations. sST2 levels were determined by enzyme-linked immunosorbent assay (ELISA), their association with post procedural mortality was investigated using logistic and Cox regression analyses, and the prognostic performance compared to established risk scores.

AS patients had substantially higher sST2 levels than controls (39.5 vs. 17.8ng/mL, p<0.001). sST2 significantly correlated with left and right atrial sizes (r=0.25, p=0.033 and r=0.38, p=0.001). At one and two years, 10 (13.9%) and 18 (25%) patients had died, respectively. sST2 significantly predicted survival in uni- and multivariate Cox regression analyses in our cohort (p=0.005 and p=0.025). sST2 also predicted major adverse cardiovascular events (MACE, p=0.046). Adding sST2 to the established STS score improved prediction of two-year mortality in our cohort (ΔAUC=0.108; 95% CI -0.066-0.281; continuous NRI=0.778; 95% CI: 0.277-1.278 and IDI=0.141; 95% CI: 0.031-0.251), and a model containing both sST2 and the STS score had a negative predictive value of 96.1% and 86.3% regarding one and two-year mortality, respectively.

sST2 is elevated in AS patients and a prognostic marker of survival after TAVI. Implementation of this marker in routine pre-TAVI workup may improve risk prediction and patient selection.