Summary

In paediatric patients with congenital heart valve disease the current concept of treatment is based on human valve transplants (allografts). However, these valves are prone to early degeneration and lack the ability to grow or remodel. As a result, multiple surgical procedures are accompanied with increasing morbidity and mortality. Tissue engineering represents an attractive pathway to overcome these limitations and raises hope for suffering patients and their relatives. Despite the promising first steps in research laboratories, a variety of questions need to be addressed prior to possible clinical application. In this issue of the Journal Dr. Kasimir and colleagues from Vienna, Austria report an interesting study highlighting one of these important topics (1) (see pages 562-7). Decellularized allografts perform better than untreated (cellularized) human allografts (2). They reveal a lower inflammation and immunological response, which is most likely related to the degenerative and calcifying potential of remaining cells in non-decellularized allografts. However, as use of human allografts is limited due to worldwide organ scarcity, decellularized xenogeneic tissues, such as porcine valves, represent one of the . . .