What causes primary pulmonary hypertension?
We don’t know the cause; there may be one or more causes. The low incidence makes learning more about the disease extremely difficult. Studies of PPH also have been difficult because a good animal model of the disease hasn’t been available. We think that in most people who develop primary pulmonary hypertension, the blood vessels are very sensitive to certain factors that trigger this disease to develop. For example, people with Raynaud’s syndrome seem more likely than others to develop PPH. In addition, appetite suppressants, cocaine and HIV are some factors believed to trigger the constriction, or narrowing, of the pulmonary artery.
