Sarcoidosis-Associated Pulmonary Hypertension

Abstract

Sarcoidosis is characterized by non-necrotizing granulomatous aggregations affecting a range of organs, with thoracic structures involved in 90% to 95% of cases. This granulomatous disease can impact the pulmonary vasculature via different mechanisms resulting in sarcoidosis-associated pulmonary hypertension (SAPH). These include postcapillary disease (left heart disease), immune-mediated granulomatous vasculopathy, hypoxemia, thromboembolism, pulmonary vascular compression and/or stenosis by mediastinal lymph nodes/fibrosis, or sarcoidosis-related portal hypertension. SAPH is a serious complication, especially in those with end-stage lung disease. A thorough evaluation is crucial to delineate the predominant mechanism of PH in the affected individual. The management of SAPH is complex and necessitates a personalized, multifaceted approach, targeting the specific mechanisms and underlying pathologies. Such patients are best served at specialized Pulmonary Hypertension and Sarcoidosis Centers. A notable phenotype within SAPH is the “pulmonary arteriopathy” group, characterized by milder parenchymal disease and a favorable response to PAH-targeted therapy, whereas patients with active granulomatous inflammation are likely to respond to immunosuppression. Several PAH therapies have been used to treat SAPH, however, clear direction on the use of PAH therapies in SAPH is still lacking. Patients receiving pulmonary vasodilators should be carefully monitored for potential deterioration in gas exchange or development of pulmonary edema, which could suggest underlying left heart disease or pulmonary veno-occlusive disease. Timely referral for lung transplant evaluation is crucial for those with SAPH and severe parenchymal lung disease, ensuring a comprehensive and patient-centered care approach. Much work remains to be done to understand the exact pathogenesis of SAPH, as well as to develop therapies that clearly improve outcomes for these patients.