All are causes of pulmonary hypeension, except?

Hypoxia leads to constriction of pulmonary aery and development of pulmonary aery hypeension. Morbid obesity leads to obstructive sleep apnea and can lead to PAH High altitude will also lead to hypoxia and development of PAH. A causal relationship has been established between exposure to several anorexigens, including aminorex and the fenfluramine, and the development of PAH.