Case report: Use of sotatercept to treat pulmonary arterial hypertension in a patient with hereditary hemorrhagic telangiectasia.

This case report describes a 45-year-old female with HHT type 1 (ENG mutation) and congenital heart disease (sinus venosus atrial septal defect and partial anomalous pulmonary venous return), diagnosed with severe PAH at age 16. Despite long-term treatment with epoprostenol, treprostinil, macitentan, and tadalafil, her condition progressed, leading to evaluation for lung transplantation. In May 2024, sotatercept, a novel TGF-β superfamily ligand trap, was initiated, resulting in significant improvement in exertional capacity and quality of life. The patient experienced increased epistaxis frequency (2-4 episodes/week), though hemoglobin levels rose from 13.0 to 15.4 g/dL. No new telangiectasias or other adverse events were noted. This is the first reported case of sotatercept use in PAH with HHT, highlighting its potential efficacy but also the need for careful monitoring due to increased bleeding risk.