# Human Epididymis Protein 4 in Transcatheter Aortic Valve Implantation: Diagnostic and Prognostic Value

## TL;DR

This study shows that high levels of HE4, a protein, predict worse outcomes after heart valve surgery, suggesting it could help doctors assess patient risk.

## Contribution

The study identifies HE4 as a novel biomarker for predicting adverse outcomes after TAVI.

## Key findings

- Higher HE4 levels are linked to increased risk of all-cause mortality after TAVI.
- HE4 is associated with diffuse myocardial fibrosis detected via cardiac MRI.
- Elevated HE4 levels predict rehospitalization and mortality following TAVI.

## Abstract

The utility of the human epididymis protein 4 (HE4) in patients undergoing transcatheter aortic valve implantation (TAVI) has not been established yet.

The present study aimed at examining the prognostic value of HE4 in patients undergoing TAVI.

In this prospective study, the prognostic value of HE4 to predict adverse clinical events was evaluated in 362 patients who underwent TAVI. The association between HE4 and diffuse myocardial fibrosis was also assessed using T1 mapping on cardiac magnetic resonance in a subgroup of 43 patients.

During a median follow-up of 2.5 (IQR: 1.9-3.2) years, 34/362 (9.4%) patients were rehospitalized for heart failure, 99/362 (27.3%) died, and 113/362 (31.2%) met the composite endpoint of rehospitalization for heart failure or all-cause mortality. In multivariable Cox regression analyses, patients with higher HE4 serum levels (ie, HE4 ≥130 pmol/L) vs lower serum levels (ie, HE4 <130 pmol/L) had increased risk of all-cause mortality (adjusted HR: 3.26 [95% CI: 2.04-5.20], P < 0.001), and of the composite endpoint (adjusted HR: 2.48 [95% CI: 1.64-3.74], P < 0.001) following TAVI, respectively. Patients with higher HE4 serum levels had higher median native T1 mapping values (1,278 [95% CI: 1,239-1,280] ms vs 1,352 [95% CI: 1,303-1,376] ms, P < 0.001) at 1 to 3 months following the procedure.

Elevated HE4 serum levels are associated with diffuse myocardial fibrosis and increased risk of adverse clinical events following TAVI. This promising blood biomarker may be helpful to enhance risk stratification in patients undergoing TAVI.