Mean change from baseline in 6-min walking distance (6MWD) in the Chronic Thromboembolic Pulmonary Hypertension Soluble Guanylate Cyclase–Stimulator Trial (CHEST)-1 and CHEST-2 studies. Mean change from baseline in 6-min walking distance (6MWD) in the Chronic Thromboembolic Pulmonary Hypertension Soluble Guanylate Cyclase–Stimulator Trial (CHEST)-1 and CHEST-2 studies. Data are observed values; error bars represent sem. Reproduced from [44] with permission from the publisher. Marius M. Hoeper Eur Respir Rev 2015;24:272-282 ©2015 by European Respiratory Society