Learning curve and analysis of curative effects after balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension. Issue 1 (5th January 2023) - Hong, Cheng; Hu, Linna; Liu, Haimin; Wu, Xiaofeng; Lu, Jianmin; Lin, Jiangpeng; Guo, Wenliang; Sun, Xishi; Lin, Jielong; Chen, Riken; Zheng, Zhenzhen