Physiopathology of pulmonary arterial hypertension in sarcoidosis
| Most frequent (in advanced stages) |
| Destruction of pulmonary capillary bed by parenchymal fibrosis |
| Others |
| Extrinsic compression of large pulmonary arteries |
| By enlarged hilar or mediastinal lymph nodes |
| By fibrosing mediastinitis |
| Vascular infiltration by noncaseating granulomas and/or perivascular fibrosis |
| Of pulmonary arteries |
| Of pulmonary veins (with pulmonary veno-occlusive disease) |
| Myocardial infiltration by noncaseating granulomas |
| Pulmonary vasoconstriction |
| By hypoxaemia |
| By other vasoactive factors |
| Liver sarcoidosis (with portal pulmonary arterial hypertension) |
Of note: multiple aetiologies can co-exist.