Impact of Preoperative Chronic Lung Disease on Survival After Surgical Aortic Valve Replacement

Abstract

An increasing number of patients requiring surgical aortic valve replacement (SAVR) present with chronic pulmonary obstructive disease (COPD). The purpose of this study was to compare patients who had a range of COPD from normal to severe and were undergoing SAVR. Retrospective review of 2,379 patients undergoing SAVR ± coronary artery bypass grafting (CABG) from January 2002 to April 2012 at a US academic institution was performed. COPD was defined according to the Society of Thoracic Surgeons (STS) adult cardiac database: normal (forced expiratory volume [FEV] > 75% predicted), mild (FEV in 1 second [FEV1] 60%-75%), moderate (FEV1 50%-59%), and severe (FEV1 < 50%). Multivariable logistic and Cox regression methods were used to determine independent association between COPD and short- and long-term outcomes. Selection bias adjustment was achieved using the STS predicted risk of mortality (PROM). Adjusted odds ratios (AORs) and adjusted hazard ratios (AHR) were calculated using the normal lung function group as the reference. Kaplan-Meier curves were created to estimate long-term survival. One thousand five hundred seventeen of 2,379 patients (63.8%) had isolated SAVR, whereas 862 of 2,379 (36.2%) patients underwent SAVR+ CABG. Preoperative COPD was common among patients (21.9%) undergoing SAVR ± CABG and included 332 (14.0%) patients with mild COPD, 89 (3.7%) patients with moderate COPD, and 101 (4.2%) patients with severe COPD. Unadjusted in-hospital mortality rose significantly with COPD class, from 3.9% for those with no COPD to 9.6% to patients with severe COPD. After adjustment, in-hospital mortality was not statistically different in normal patients and in those with COPD. In contrast, when compared with normal patients, adjusted long-term survival was worse across levels of COPD: mild (AHR, 1.70; p < 0.001), moderate (AHR, 2.25; p < 0.001), and severe (AHR, 2.28; p < 0.001). Preoperative COPD is common in the SAVR population and is associated with diminished long-term but not short-term survival.