Cardiovascular physiology during fetal development and implications for tissue engineering.

Shear stress in fluid dynamics has a well-known impact on vascular cell morphology, proliferation, orientation, and the organization and composition of extracellular matrix. There is an increasing interest in the field of tissue engineering to use defined shear stress in bioreactors for tissue conditioning and guided tissue formation. Especially for cardiovascular structures like heart valves or blood vessels, the type and appropriate amount of shear stress needed to improve tissue formation remains speculative. The authors believe that fetal-like conditions may be more optimal for new tissue formation in a bioreactor. The purpose of this review is to delineate parameters of cardiovascular physiology during embryonic and fetal development that may have a potential impact on the design and setting of bioreactors for cardiovascular tissue engineering.