Carinal replacement with an aortic allograft.
BACKGROUND
Carinal replacement after extensive resection remains a tremendous challenge in thoracic surgery. In previous studies, we demonstrated that an aortic graft could be a valuable tracheal substitute. The goal of this new study was to evaluate the reconstruction of the carina using a stent supported bifurcated aortic allograft.


METHODS
In 15 sheep the replacement of the tracheobronchial bifurcation with an aortic allograft was performed under cardiopulmonary bypass. A temporary stent prevented airway collapse. No immunosuppression was used. Aortic segments were retrieved at regular intervals up to 24 months after implantation.


RESULTS
All animals survived the initial aortic allograft operation. Six animals died postoperatively (1 of graft necrosis, 2 of pneumonia, and 3 of bronchial fistula). The remaining 9 animals were in good condition until they were euthanized. Stent removal was tolerated after 9 months in 3 animals. Progressive transformation of the arterial graft initially into extensive inflammatory tissue, and after 3 to 6 months into a tracheal tissue comprising a well-differentiated epithelium and cartilage was confirmed by histology.


CONCLUSIONS
This study showed that regeneration of a functional tissue can be obtained after replacement of the carina with an aortic allograft. The origin and mechanisms of this regenerative process remains to be discovered. These results represent an important hope for the reconstruction of the carina after extensive resection, especially for cancer lesions. In human application, the systemic use of omentoplasty or myoplasty should further reduce its risk of complication.
Laboratoire d'Etude des Greffes et Prothèses Cardiaques, Hôpital Broussais, Paris, France. agatheseguin@wanadoo.fr
Agathe
A
Seguin
Emmanuel
E
Martinod
Marianne
M
Kambouchner
Gabriella O
GO
Campo
Pascale
P
Dhote
Patrick
P
Bruneval
Jacques F
JF
Azorin
Alain
A
Carpentier
D000818:Animals; D001013:Aorta, Thoracic / Q000637:transplantation*; D002315:Cardiopulmonary Bypass / Q000379:methods; D006801:Humans; D023421:Models, Animal; D019188:Organ Preservation Solutions; D012756:Sheep; D013908:Thoracotomy; D020858:Tissue and Organ Harvesting / Q000379:methods; D014132:Trachea / Q000601:surgery*; D014184:Transplantation, Homologous
D019188:Organ Preservation Solutions