The blood supplying the lungs consists predominantly of deoxygenated blood from the pulmonary arterial tree and the much smaller systemic arterial bronchial arteries.1 Although the bronchial arteries are known to bring oxygenated and nutritious blood supply to the bronchial tree, this blood supply is sacrificed during lung transplantation and leads to airway ischemia, which has historically been one of the Achilles heels of lung transplantation.
Modern day lung transplantation began on November 7, 1983, when Dr. Joel Cooper performed the first lung transplantation on a dying patient with cystic fibrosis. In the early days, the lungs were transplanted en bloc with a tracheal anastomosis. It did not take long before airway ischemia was determined to be a major issue owing to the lack of tracheal/bronchial circulation, with airway dehiscence and necrosis occurring in as many as 40% of cases.2 Despite techniques such as omental wrapping, which has been shown to augment airway healing in an animal model, airway complications in humans were not satisfactorily addressed.3 The obvious solution, promoted by four groups from around the world in the early 1990s, was bronchial artery revascularization (BAR).
The first published series of results for the BAR approach took place in Bordeaux, France, in 1992; Harefield Hospital in the UK in 1993; and Mayo Clinic in the United States and Copenhagen, Denmark, both in 1994.4–10 The early benefit of BAR was seen immediately because it essentially eliminated airway complications from ischemia. However, the technique was slow to gain worldwide acceptance owing to the high degree of technical difficulty, prolongation of ischemia and operative times, and increased risk of bleeding. At the same time, it was recognized that intraparenchymal segments of bronchi were more resistant to ischemia than the trachea and extraparenchymal bronchus, and by cutting the airways at the level of the secondary carina, many of the airway complications could be avoided. In addition, decreasing the dose and duration of the immunosuppression regimen has also improved airway healing.11 Consequently, en bloc double-lung transplantation (DLTx) with tracheal anastomosis was abandoned in favor of bilateral sequential lung transplantation (BLTx) with bronchial anastomosis. BAR was likewise abandoned, even by those centers that pioneered the technique. In Copenhagen, Denmark, Gosta B. Pettersson (hereafter, GBP) had performed a total of 106 transplants with BAR, and, to this day, his work represents the largest series of BAR. Even in Copenhagen, BAR was superseded by BLTx after GBP moved to the Cleveland Clinic.
Over time, the focus on early mortality due to airway complications shifted to progressive organ dysfunction from chronic lung allograft dysfunction (CLAD). Currently, median survival after lung transplantation is around 5.8 years and 5-year survival is 54% according to the International Society for Heart and Lung Transplantation (ISHLT) database; these results lag significantly behind the long-term survival seen with other solid organs.12