Living-Donor Lobar Lung Transplantation for Pulmonary Arterial Hypertension

Abstract

Living-donor lobar lung transplantation (LDLLT) was developed in the University of Southern California (USC) to offset the mismatch between supply and demand for those patients awaiting cadaveric lung transplantation (CLT). A single donor was used in the beginning and successful living-donor single lobe transplantation was reported. However, the following experience of single lobe transplantation was not satisfactory. It is for this reason that the USC group developed a bilateral LDLLT in which two healthy donors donate their right or left lower lobes. Because only two lobes are transplanted, LDLLT seems to be best suited for children and small adults, and was applied most exclusively to cystic fibrosis patients in the beginning. Pulmonary arterial hypertension (PAH) is defined as a group of diseases characterized by a progressive increase in pulmonary vascular resistance. Until the introduction of intravenous epoprostenol therapy in the 1990s, the disorder was rapidly progressive, leading to death in a median of 2.8 years from diagnosis. Epoprostenol, a potent shortacting vasodilator and inhibitor of platelet aggregation, was a therapeutic breakthrough that brought new hope to patients with PAH. In long-term follow-up studies of patients with idiopathic PAH (IPAH) receiving intravenous epoprostenol therapy, 3-year survival ranged from 62 to 88%. Bilateral CLT remains the treatment of last resort when medical therapy has failed. However, compared with other conditions for which CLT is performed, patients with IPAH had the highest risk of death within the first year of CLT. The 3-year survival rate after CLT was reported to be less than 60%, which was worse than that of patients receiving epoprostenol treatment. We and others have expanded the indications for LDLLT to include both pediatric and adult IPAH patients. As of 2008, LDLLT had been performed in approximately 300 patients with various lung diseases worldwide. In this chapter, the current status of LDLLT for PAH is summarized.