Scientists from the Sant’Anna School of Advanced Studies in Pisa have found that the right cardiac vagus nerve plays a key role in maintaining the heart’s “youthfulness,” protecting heart cells and supporting their function independently of heart rate. The findings were published in Science Translational Medicine (STM).

The vagus nerve is the main conduit of the parasympathetic nervous system, which is responsible for recovery processes and the body’s “energy-saving mode.” In the heart, it helps reduce the load on cardiomyocytes and protects cardiac tissue from premature wear. However, during thoracic surgery or heart transplantation, the right vagus nerve may be damaged or severed, disrupting autonomic control and accelerating the development of cardiac dysfunction.

In experiments on adult minipigs, the researchers showed that early restoration of the right vagus nerve helps preserve the mechanical function of the heart. To achieve this, they used a biodegradable implantable nerve guide in the form of a cuff made of chitosan (derived from the chitin in crustacean shells) and the polymer ε-caprolactone. The device guided the growth of nerve fibers and promoted their spontaneous regeneration.

Animals with restored innervation showed improved cardiac muscle contraction, reduced discoordination of relaxation, and fewer signs of oxidative stress and cellular aging. Histological analysis revealed partial restoration of the vagus nerve, the return of parasympathetic fibers to the myocardium, and prevention of fibrosis—the replacement of muscle tissue with connective tissue.

The authors emphasize that preserving bilateral vagal innervation of the heart may be an important factor in slowing cardiac aging. In the future, the developed nerve guide could become a new approach to preventing heart failure in patients after thoracic surgery and cardiothoracic transplantation.