A 64-year-old woman presented with exertional dyspnoea and ankle oedema. She had lung biopsy-confirmed sarcoidosis 6 years previously, having initially responded to prednisolone, with clinical stability for several years. Pulmonary function tests (PFTs) showed forced expiratory volume in 1 s, 2 litres; forced vital capacity, 2.5 litres; and carbon monoxide transfer factor, 4.03 (49.2% predicted). Chest radiography showed Scadding stage 4 sarcoidosis with prominent hila and coarse reticulation throughout both lungs. CT showed stable fibrotic features and ground-glass opacification, new right lower lobe interlobular septal thickening and right-sided pleural effusion (figure 1A). Echocardiography suggested severe pulmonary hypertension (PH) (estimated right ventricular (RV) systolic pressure 68 mm Hg) with RV dilatation, with confirmed precapillary haemodynamics on right heart catheterisation. Cardiac MRI revealed abnormal remodelling of the RV (without evidence of cardiac sarcoidosis); cardiac gated contrast CT angiography and ultimately …