Pino JE, et al. - Researchers examined whether preoperative risk stratification of patients undergoing transcatheter aortic valve replacement (TAVR) can be performed using pulmonary function testing (ie, FEV1), arterial blood gases (ie, PO₂), the diagnosis of chronic obstructive lung disease (COPD) by the Global Initiative for COPD (GOLD), and the diagnosis of chronic lung disease (CLD) by the Society of Thoracic Surgeons (STS). Among 513 patients who underwent TAVR, STS criteria revealed CLD in 269 (52%) patients with a mean FEV1 of 55.4 ± 12%. GOLD criteria revealed COPD in 158 (30%) patients with a mean FEV1/forced vital capacity of 61.8 ± 8.2%. Changes in ejection fraction, albumin, creatinine, and B-type natriuretic peptide levels affected the severity of CLD but not the severity of COPD. Heightened risk of 30-day mortality was noted in correlation to an increased A-a gradient, increased PCO₂, and decreased arterial blood gases. Isolated abnormalities in spirometry are suggested to be a poor indicator of clinically relevant outcomes in TAVR.