Secondary pulmonary hypertension does not adversely affect outcome after single lung transplantation

Primary and secondary pulmonary hypertension have been associated with poor outcomes after single lung transplantation. Some groups advocate double lung transplantation and the routine use of cardiopulmonary bypass during transplantation in this population. However, the optimal procedure for these patients remains controversial. The goal of our study was to determine the safety of single lung transplantation without cardiopulmonary bypass in patients with secondary pulmonary hypertension.

We retrospectively reviewed 76 consecutive patients with pulmonary parenchymal disease who underwent single lung transplantation from 1992 to 1998. Recipients were stratified according to preoperative mean pulmonary artery pressure. Secondary pulmonary hypertension was defined as parenchymal lung disease with a preoperative mean pulmonary artery pressure of 30 mm Hg or more. Patients with primary pulmonary hypertension or Eisenmenger's syndrome were excluded from analysis.

Eighteen of 76 patients had secondary pulmonary hypertension. No patient with secondary pulmonary hypertension required cardiopulmonary bypass, whereas 1 patient without pulmonary hypertension required bypass. After the operation, no significant differences were seen in lung injury as measured by chest radiograph score and PaO(2)/FIO(2) ratio, the requirement for inhaled nitric oxide, the length of mechanical ventilation, the intensive care unit or hospital length of stay, and 30-day survival. There were no differences in the forced expiratory volume in 1 second or 6-minute walk at 1 year, or the incidence of rejection, infection, or bronchiolitis obliterans syndrome greater than grade 2. Survival at 1, 2, and 4 years after transplantation was 86%, 79%, and 65%, respectively, in the low pulmonary artery pressure group and 81%, 81%, and 61%, respectively, in the group with secondary pulmonary hypertension (P >.2).

We found that patients with pulmonary parenchymal disease and concomitant secondary pulmonary hypertension had successful outcomes as measured by early and late allograft function and appear to have acceptable long-term survival after single lung transplantation. Our results do not support the routine use of cardiopulmonary bypass or double lung transplantation for patients with this disorder.