What are causes of pulmonary hypertension?
The exact cause of PPH is unknown. Research has linked primary pulmonary hypertension to genetic or familial predisposition. Researchers believe the blood vessels are particularly sensitive to certain internal or external factors, and constrict, or narrow, when exposed to these factors, such as an immune system factor, or sensitivity to drugs or other chemicals.Secondary pulmonary hypertension occurs as a result of the effects of other conditions which may include diseases of the heart or lungs, a blood clot in the lungs, or a condition called scleroderma.
