Development of a nonthrombogenic collagenous blood-prosthetic interface

Area of Science:

• Biomedical Engineering
• Materials Science
• Cardiovascular Research

Background:

• Implantable assist pumps for circulatory support face challenges due to thrombus formation and embolization on prosthetic surfaces.
• Friable thrombus accumulation on artificial interfaces impedes long-term device function and patient safety.

Purpose of the Study:

• To investigate the efficacy of a fibroblast-inoculated polyurethane surface for preventing thromboembolic complications in an implantable assist pump.
• To create a biocompatible interface that promotes cellular adhesion and reduces adverse blood-material interactions.

Main Methods:

• Cultured bovine fetal fibroblasts were inoculated onto a textured polyurethane pump chamber prior to implantation in calf models.
• The pneumatically actuated device maintained pulsatile blood flow, with cell viability and adherence assessed over extended periods (up to 335 days).
• Biologic lining thickness, composition (collagen, elastin), and immunologic response were analyzed post-explantation.

Main Results:

• A densely adherent biologic lining, composed of fibroblasts and collagen, formed on the polyurethane surface.
• Minimal cell washout was observed after device connection to the circulation.
• No thromboembolic complications or significant immunologic responses were detected in the animal recipients.

Conclusions:

• An induced collagenous-blood interface using fibroblasts effectively prevented thromboembolic complications.
• This approach facilitates prolonged mechanical circulatory support with implantable assist devices.
• The findings support the potential of bio-integrated surfaces for advanced medical devices.