Abstract

Identification of prognostic biomarkers in patients undergoing transfemoral transcatheter aortic valve implantation

Author(s): Luisa Nowicki, Oliver Dorr

As surgical risk scores overestimate mortality, risk prediction in patients with severe Aortic Stenosis (AS) undergoing Transcatheter Aortic Valve Implantation (TAVI) remains an unresolved issue. We, therefore, investigated whether the novel biomarkers Mid-Regional pro-Adrenomedullin (MR-proADM) and Growth Differentiation Factor 15 (GDF-15) could add value to risk assessment. Serum levels of 92 patients were collected and stratified by survival. Not only presented patients who died during the follow-up period higher biomarker levels ((MR-proADM (Survivors: 0.922 nmol/l (0.706-1.202) vs. Decedents: 1,347 nmol/l (1,038-1,678), p=0.0003)); (GDF-15 (Survivors: 1675.2 pg/ml (1141.6; 2524.4) vs. Decedents: 2770.0 pg/ml (2401.0- 3701.0), p=0.0006))) before TAVI, but by using Kaplan-Meyer analysis in conjunction with Youden index we were able to identify a specific cut-off value determining survival that reached a good level of discrimination ((MR-proADM: AUC=0.73, 95% CI (0.61; 0.85), p=0.002); (GDF-15: AUC=0.73, 95% CI (0.61; 0.85), p=0.002))). The inclusion of the presented biomarkers into binary logistic regression further improved the prognostic value of classical risk predictors (AUC=0.811 (Standard error 0.05; 95% CI (0.693; 0.899)). In addition, serum levels of pro-ADM decreased significantly in surviving patients after TAVI. Therefore, novel biomarkers have the potential to improve risk stratification in patients undergoing TAVI through the provision of individualized and objective information.