# In Vitro Calcification Evaluation of Polycarbonate Urethane—Impact of Production Processes

## TL;DR

This study finds that the production method of a heart valve material affects its tendency to calcify, with hot pressing increasing calcification risk.

## Contribution

The study reveals that hot pressing alters the chemical structure of polycarbonate urethane, increasing calcification propensity.

## Key findings

- Hot-pressed polycarbonate urethane patches showed calcification, while solution-cast patches did not.
- Hot pressing caused chemical and structural changes in the material, likely promoting calcification.
- Cytocompatibility was similar between hot-pressed and solution-cast polycarbonate urethane.

## Abstract

Heart valve diseases remain a leading cause of death in industrialized nations. Polycarbonate urethane (PCU) is a promising material for heart valve prostheses due to its biocompatibility and low calcification tendency. However, the impact of processing methods on calcification remains unclear.

PCU patches were fabricated via hot pressing or solution casting. Both groups (n = 3 each), along with bovine pericardium patches as positive controls (n = 3), were incubated for 10 weeks in a custom in vitro calcification fluid. Calcification, cytocompatibility, and material properties were assessed using light and electron microscopy, infrared spectroscopy, and gel permeation chromatography (GPC).

Calcification was observed in hot‐pressed PCU and control patches but not in solution‐cast PCU. Both PCU types showed comparable cytocompatibility. Spectroscopy and GPC revealed chemical and structural changes in hot‐pressed PCU, likely promoting calcification.

Hot pressing alters the chemical structure of PCU and increases its calcification propensity without affecting cytocompatibility. These findings highlight the importance of process control and in vitro screening during heart valve material development.

The study shows that hot pressing induces chemical changes in PCU, promoting calcification, while solution‐cast patches remain unaffected.