675 Severity of Pulmonary Hypertension Predicts Short Term Lung Transplantation Outcomes in Subjects with Chronic Obstructive Pulmonary Disease

Abstract

Purpose: Pulmonary hypertension (PH) is a common complication of chronic obstructive pulmonary disease (COPD), which is usually of mild severity. Whether PH severity in COPD subjects bears upon clinical outcomes following lung transplantation is not clear. We seek to determine whether echocardiography-based PH severity at time of lung transplant assessment predicts inferior short and long term outcomes post lung transplantation. Methods and Materials: Retrospective analysis including all lung transplant recipients at The Alfred between 2000 and 2009 for a primary diagnosis of COPD who underwent echocardiography at The Alfred. Only patients with a documented right ventricular systolic pressure (RVSP) were included. Patients were allocated into three groups based on their RVSP: No PH if RVSP 35 mmHg; Mild PH if 35 RVSP 45 mmHg; and Moderate-Severe PH if RVSP 45 mmHg. Outcome measures were ICU length of stay, time until extubation and PaO2/fraction inspired oxygen (PaO2/FiO2) ratio at 24 hours. Survival was measured at 30 days, 12 months, 5 years and overall. Results: Of 138 COPD lung transplant patients, 94 (68%) underwent echocardiography at The Alfred and 46 (33%) had documented RVSP. There were no differences in baseline demographics, pulmonary function, blood gases or cardiac function between the three PH groups. ModerateSevere PH predicted increased time until extubation (p 0.05), worse PaO2/FiO2 ratio at 24 hours (p 0.05), worse 12 month survival (p 0.05) and a trend toward increased ICU length of stay (p 0.06). We did not observe any significant differences between the groups for 30 day, 5 year or overall survival. RVSP was significantly correlated with ICU length of stay (r 0.513, p 0.001) and time until extubation (r 0.586, p 0.0001). Conclusions: PH severity predicts short term outcomes post lung transplantation in COPD subjects. The mechanisms through which COPD subjects with moderate-severe PH have inferior clinical outcomes following lung transplantation are yet to be elucidated.