Prognostic utility of mid-regional pro-adrenomedullin and growth differentiation factor 15 in patients undergoing transfemoral transcatheter aortic valve implantation

Abstract

Background: Risk prediction in patients with severe, symptomatic aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI) remains an unsolved issue. In addition to classical risk scoring systems, novel circulating biomarkers like mid-regional pro-adrenomedullin (MR-proADM) and growth differentiation factor 15 (GDF-15) may be of value in assessing risk. Methods: Consecutive patients undergoing elective transfemoral TAVI were included in this prospective observational study. Baseline information, imaging findings, blood samples, and clinical outcomes were collected. Blood levels of the classical biomarkers interleukin-6 (IL-6) and high-sensitivity C-reactive peptide (hsCRP) and of the novel biomarkers MR-proADM and GDF-15 were measured and their predictive utility for mortality assessed. Results: The study cohort consisted of 92 patients undergoing TAVI. The median age was 80.7 years [IQR 77.2;83.3], and 48 (52.2%) were male. Analysis of the area under the curve (AUC) of the receiver-operating characteristics showed that the hsCRP levels discriminated poorly (AUC 0.66, 95% CI [0.52;0.8], p = 0.027), whereas all other biomarkers reached a higher level of discrimination (IL-6: AUC 0.76, 95% CI [0.66;0.86], p < 0.001; 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). Kaplan–Meier analysis in conjunction with Youden J-statistics yielded the optimal cutoff points for each biomarker to predict survival: IL-6 4.65 pg/mL, hsCRP 12.9 mg/L, MR-proADM 1.02 nmol/L, and GDF-15 2400.1 pg/mL. Conclusion: Novel circulating biomarkers like MR-proADM and GDF-15 may provide additional value in predicting survival after TAVI.