NPPB and chronic thromboembolic pulmonary hypertension: There was no significant difference between CTEPH patients with proximal disease (n = 5) and other PH patients (n = 15, other PH etiologies) based on cardiac catheterization data: PVR (P = 0.4), MPAP/TPG (P = 1.0/P = 0.7), pulse pressure (P = 0.6), or clinical parameters: 6-min walk test (P = 0.9), serum NT-pro-BNP (P = 0.8), and CMR RVEF (P = 0.9).