<unk>  <unk>  or<unk> N) is a condition of increased blood pressure in the arteries of the lungs. Symptoms include shortness of breath, fainting, tiredness, chest pain, swelling of the legs, and a fast heartbeat. The condition may make it difficult to exercise. Onset is typically gradual. A patient is deemed to have<unk>  if the pulmonary mean arterial pressure is greater than 25mmHg at rest, or greater than 30mmHg during exercise. The cause is often unknown. Risk factors include a family history, prior blood clots in the lungs, HIV/AIDS, sickle cell disease, cocaine use, chronic obstructive pulmonary disease, sleep apnea, living at high altitudes, and problems with the mitral valve. The underlying mechanism typically involves inflammation and subsequent remodeling of the arteries in the lungs. Diagnosis involves first ruling out other potential causes. There is currently no cure for<unk> , although research on a cure is ongoing. Treatment depends on the type of disease. A number of supportive measures such as oxygen therapy, diuretics, and medications to inhibit blood clotting may be used. Medications specifically used to treat<unk>  include epoprostenol, treprostinil, iloprost, bosentan, ambrisentan, macitentan, and sildenafil. Lung transplantation may be an option in severe cases. The frequency of occurrence is estimated at 1,000 new cases per year in the United States. Females are more often affected than males. Onset is typically between 20 and 60 years of age.<unk>  was identified by Ernst von Romberg in 1891.
Pulmonary hypertension
Portopulmonary hypertension
Chronic thromboembolic pulmonary hypertension
Asthma
Chronic obstructive pulmonary disease
Emphysema
Hypertensive heart disease
Reactive airway disease