Pulmonary vasodilators: beyond the bounds of pulmonary arterial hypertension therapy in COVID-19

Pulmonary arterial hypertension (PAH) and novel coronavirus (SARS-CoV-2) disease COVID-19 are characterized by extensive endothelial dysfunction and inflammation leading to vascular remodeling and severe microthrombi and microvascular obliterative disease. It is hypothesized that those patients with underlying lung disease, like PAH, represent a high-risk cohort in this pandemic. However, reports of COVID-19 in this cohort of patient have been scaring and an observational survey showed that the disease was relatively well tolerated. We postulate that specific PAH vasodilator may offer some protection and/or advantage in the case of concomitant COVID-19. Here we review the literature describing mechanisms of action for each of the broad categories of PAH therapy, and offer potential hypothesis about why this therapy may impact outcomes in COVID-19.