Hematoxylin and eosin (HE) staining of “neo-ventricle” 56 days after implantation around the superior caval vein (SVC) of rats.

<p>A: Engineered heart tissue organized around the SVC. Thick bundles of cross-striated cardiomycytes are shown above the smooth muscle of the native vessel wall. The arrow indicates a suture with surrounding lymphocytic infiltration. B: Magnification of detail in left panel. Cross-striation can be seen in the highly organized cardiomyocytes within the contractile conduit. The arrow indicates red blood cells in a capillary. Scale bar: 50 μm.