Idiopathic multiple arterial stenoses

Chronic thromboembolic pulmonary hypertension (CTEPH) is a long-term disease caused by a blockage in the blood vessels that deliver blood from the heart to the lungs (the pulmonary arterial tree). These blockages cause increased resistance to flow in the pulmonary arterial tree which in turn leads to rise in pressure in these arteries (pulmonary hypertension). [Source: Wikipedia ]