In some aspects, the disclosure relates to GDF/BMP antagonists and methods of using GDF/BMP antagonists to treat, prevent, or reduce the progression rate and/or severity of pulmonary hypertension (PH), particularly treating, preventing or reducing the progression rate and/or severity of one or more PH-associated complications. The disclosure also provides methods of using a GDF/BMP antagonist to treat, prevent, or reduce the progression rate and/or severity of a variety of conditions including, but not limited to, pulmonary vascular remodeling, pulmonary fibrosis, and right ventricular hypertrophy. The disclosure further provides methods of using a GDF/BMP antagonist to reduce right ventricular systolic pressure in a subject in need thereof.