Patients with severe pulmonary hypertension unresponsive to other modes of therapy who are otherwise healthy, of reasonable age (generally 60), and have adequate psychosocial strength and family (or important other) support should be considered for possible lung transplantation. Significant renal, hepatic, or coronary vascular disease is usually considered a significant impediment to lung transplantation. Most experts now consider transplant when signs of right heart failure develop, but some advocate earlier transplantation.
Is bilateral lung transplantation better than single lung transplantation in patients with severe pulmonary hypertension?
For: Single lung transplantation in severe pulmonary hypertension is associated with more postoperative and long-term complications. In the postoperative period, the grafted lung is highly susceptible to the development of pulmonary edema due to ischemia and reperfusion. The majority of blood flow is directed toward the graft by the high resistance to flow in the remaining native lung, increasing the likelihood of pulmonary edema. Ventilation is directed to the remaining native lung, however, causing ventilation-perfusion mismatch. In addition, the long-term risks associated with rejection and infection are also greater. As with reperfusion edema, rejection or pneumonia in the single lung transplant can lead to mismatching of ventilation and perfusion. For all these reasons, it is likely, though not proven, that bilateral lung transplantation leads to better long-term survival than single lung transplantation.
Against: Bilateral lung transplantation is thought to be associated with a higher intraoperative risk than single lung transplantation, due to the longer and more complicated operation. Bilateral lung transplantation also uses up more donor organs and may lengthen waiting times for the patient as well as others on the list, thereby increasing their risk of dying while awaiting transplantation. If the overall goal is to help as many patients as possible, bilateral lung transplantation, in the absence of convincing evidence of improved long-term survival, is difficult to justify.
Current Practice: We currently lean toward single’ lung transplantation in older candidates and bilateral lung transplantation in younger candidates. However, there are no studies to support this, and a randomized multicenter trial is needed.