Practices affEcting macitentan and selexipag patient persistence Rates utilizing pulmonary arterial hypertension clinical Site and patIent perSpecTives (PERSIST): a US qualitative analysis

Dear Editor,
We thank Drs. Perros, Chaveroux, and Montani for their interest in our articles describing the activation of the integrated stress response (ISR) pathway as a mechanism underlying the pathogenesis of pulmonary veno-occlusive disease (PVOD), based on the rat mitomycin C (MMC) model of PVOD.

To the Editor,
We read with great interest the recent paper by Prabhakar et al., “Mechanisms underlying age-associated exacerbation of pulmonary veno-occlusive disease,”1 which investigates the role of the integrated stress response (ISR) in pulmonary veno-occlusive disease (PVOD).

Pulmonary arterial hypertension (PAH) is a severe disease caused by progressive distal pulmonary artery obstruction. One cause of PAH are loss-of-function mutations in the potassium channel subfamily K member 3 (KCNK3). KCNK3 encodes a two-pore domain potassium channel, which is crucial for pulmonary circulation homeostasis. 

The objective of this analysis was to compare clinician-based and formally calculated risk assessments by REVEAL Lite 2 and COMPERA 2.0 and to characterize parenteral prostacyclin utilization within 90 days of baseline in high-risk patients. A multisite, double-blind, retrospective chart review of patients with pulmonary arterial hypertension (PAH) was conducted with an index period of January 2014–March 2017.