Image: Aortas from deceased donors can be used to reconstruct the trachea (Photo courtesy of JAMA).
A new study suggests that airway bioengineering using stented aortic matrices is a feasible alternative for complex tracheal and bronchial reconstruction.
Researchers at Université Paris Descartes (France), Université Paris Denis Diderot (France), and other institutions conducted an uncontrolled, single-center cohort study that included 20 patients (mean age 54.9 years; 65% male) with end-stage tracheal lesions or with proximal lung tumors requiring a pneumonectomy in order to establish the feasibility of airway bioengineering, using a technique based on the implantation of stented aortic matrices.
Study participants underwent radical resection of the lesions using standard surgical techniques. After resection, airway reconstruction was performed using a human cryopreserved (−80°C) aortic allograft, which was not matched by the ABO and leukocyte antigen systems. To prevent airway collapse, a custom-made stent was inserted into the allograft. In all, 13 patients underwent tracheal, bronchial, or carinal transplantation. In patients with proximal lung tumors, a lung-sparing bronchial transplantation intervention was performed. The main outcomes were 90-day mortality and morbidity.
The results revealed that one patient who underwent a carinal transplantation died. No mortality at 90 days was observed among patients who underwent tracheal or bronchial reconstruction. Among the 13 patients who underwent airway transplantation, major morbidity events occurred in four, including laryngeal edema, acute lung edema, acute respiratory distress syndrome (ARDS), and atrial fibrillation (AF). No adverse event was directly related to the surgical technique. Stent removal was performed 18 months later. Of the 10 patients surviving at three-year follow-up, 80% breathed normally through newly formed airways. The study was published on May 20, 2018, in JAMA.
“Airway bioengineering using stented aortic matrices is a feasible alternative for complex tracheal and bronchial reconstruction. Regeneration of epithelium and de novo generation of cartilage was observed within aortic matrices from recipient cells,” concluded lead author Emmanuel Martinod, MD, PhD, of Université Paris Descartes, and colleagues. “Epithelial cells have gradually repopulated the allograft lumen by direct migration, by expansion from adjacent native airways (as observed after epithelium destruction), or by both.”
The researchers used aortas from deceased donors to replace damaged sections of trachea, as the thick walls of aortas are designed to withstand a lifetime of pressure, channeling blood pumped by the heart. The aortas can be frozen to minus 80 degrees Celsius and stored, ensuring an ample supply. An added benefit is that the freezing process removed the need for a life-long regimen of medications to prevent the immune system from rejecting the transplanted organ.
Université Paris Descartes
Université Paris Denis Diderot