A groundbreaking advancement in cardiac tissue engineering offers new hope for individuals suffering from mitral valve disease. For the first time globally, a bioengineered tendon cord has been successfully implanted in a large animal model – a sheep – representing a significant step towards regenerative heart valve therapies.
The procedure, performed on , by Professor Maria Grandinetti of the Università Cattolica del Sacro Cuore, is part of the BioChord project. This project is coordinated by the Fondazione Rimed and supported by a Proof of Concept Grant from the European Research Council, a prestigious European scientific research program.
Understanding Mitral Valve Disease and Current Treatments
The mitral valve, located between the left atrium and left ventricle of the heart, plays a crucial role in ensuring efficient blood flow. Its deterioration or rupture can lead to mitral regurgitation, a condition affecting over 24 million people worldwide. In mitral regurgitation, blood leaks backward through the valve when the heart contracts, reducing the heart’s efficiency and potentially leading to heart failure.
Currently, treatment options for mitral valve disease often involve surgical interventions utilizing synthetic materials, typically expanded polytetrafluoroethylene (ePTFE). While durable, these synthetic materials lack the biological properties of natural tissue. This can result in complications such as stiffness, fibrosis (scar tissue formation) and the eventual need for further interventions. The limitations of synthetic materials have driven the search for more biocompatible and regenerative solutions.
BioChord: A Tissue-Engineered Approach
The BioChord project takes a fundamentally different approach, focusing on tissue engineering rather than simply providing a synthetic substitute. “It’s not simply a suture material, but tissue engineering,” explains Antonio D’Amore, project leader at Rimed and a professor at the University of Palermo and the University of Pittsburgh. The core innovation lies in the bioengineered chordae tendineae – the “tendon-like” structures that support the mitral valve. These structures are essential for proper valve function, acting as “pullers” to ensure synchronized opening and closing during each heartbeat.
Unlike traditional synthetic sutures, the bioengineered chordae tendineae are designed to mimic the natural structure of the native tissue. Critically, they are also intended to degrade over time, allowing the patient’s own tissue to integrate and ultimately replace the implanted structure. This bioresorbable characteristic is a key advantage, potentially minimizing long-term complications associated with permanent synthetic implants.
Biomechanical Considerations in Mitral Valve Repair
Recent research highlights the importance of biomechanical considerations in mitral valve repair. A study published in in PubMed investigated biomechanical differences among various mitral repair techniques in a large animal model using sheep. The study found that neochord repair and nonresectional leaflet remodeling techniques reduced peak chordal forces compared to the prolapsed state. The number of neochordae used in repair significantly impacted peak primary chordal forces, with fewer neochordae resulting in higher forces. These findings underscore the need for precise biomechanical evaluation and optimization of repair techniques.
While the BioChord project focuses on a bioengineered chordae tendineae, other interventional devices for mitral valve repair involving artificial chords are also under development, as noted in a review published by Frontiers. These devices aim to provide alternative solutions for repairing or replacing damaged mitral valve structures.
Looking Ahead: From Pre-Clinical Testing to Clinical Applications
The successful implantation in a sheep represents a crucial step forward, moving the BioChord project from laboratory development to pre-clinical testing. This achievement demonstrates the feasibility and potential of this tissue-engineered approach. However, significant research and development remain before this technology can be translated into clinical applications for human patients.
Further studies will be necessary to evaluate the long-term safety and efficacy of the bioengineered chordae tendineae, as well as to optimize the manufacturing process and surgical techniques. The research team will also need to address potential challenges related to immune response and tissue integration. Despite these challenges, the BioChord project offers a promising new avenue for treating mitral valve disease, potentially improving the lives of millions affected by this condition.
The development of a prosthesis that can transform into natural tissue represents a paradigm shift in cardiac surgery. By harnessing the principles of biomimicry and tissue engineering, researchers are paving the way for regenerative therapies that offer the potential for more durable, biocompatible, and effective solutions for mitral valve repair.
