Smallest cardiac veins contribute to normal physiologic shunting of blood. As a consequence of the input of these vessels, blood in the left heart is less oxygenated than the blood found at the pulmonary capillary beds, albeit to a very small degree. The "openings of smallest cardiac veins" are located in the endocardium. Here the smallest cardiac veins return blood into the heart chambers from the capillary bed in the muscular cardiac wall, enabling a form of collateral circulation unique to the heart. Not every endocardial opening connects to the thebesian veins as some connect to the vessels of Wearn, which are arteries.
Face transplant the sinuses around the nose, the upper jaw, and even some teeth from a brain-dead donor. As doctors recovered the donor's facial tissue, they paid special attention to maintaining arteries, veins, and nerves, as well as soft tissue and bony structures. The surgeons then connected facial graft vessels to the patient's blood vessels in order to restore blood circulation in the reconstructed face before connecting arteries, veins and nerves in the 22-hour procedure. She had been disfigured to the point where she could not eat or breathe on her own as a result of a traumatic injury several years ago,