Abstract
For severe heart failure because of congenital heart disease, coronary artery disease, and dilated cardiomyopathy, heart transplantation is the definitive treatment approach for patients. However, a lack of donor organs remains a longstanding and serious problem worldwide. Artificial hearts, such as left ventricular assist devices, present problems related to thromboembolism, infection, gastrointestinal bleeding, and finite durability. Direct injection of isolated skeletal myoblasts and bone marrow-derived cells or cardiac stem cells has already been used clinically as a method to improve heart function by regenerating the myocardium and blood vessels. However, direct injection of the dissociated cells has shown to be slightly effective, and it is often difficult to control the form, dimensions or position of implanted cells. In an attempt to solve these problems, research has been initiated on reconstructing functional three-dimensional cardiac grafts using tissue engineering methods as a treatment for the next generation. Cell sheet transplantation has already been shown to be able to cure damaged hearts. In addition to cardiac patches transplanted directly onto damaged hearts, the next challenge is to fabricate organ-like tissues, such as tubular or spherical structures that are able to function as a cardiac pump with the potential for circulatory support.
