Pulmonary arterial hypertension
(PAH) is a progressive condition that affects the heart and lungs. It is characterized by abnormally high blood pressure (hypertension) in the pulmonary artery, the blood vessel that carries blood from the heart to the lungs. The most common signs and symptoms are shortness of breath (dyspnea) during exertion and fainting spells. As the condition worsens, people can experience dizziness, swelling (edema) of the ankles or legs, chest pain, and a racing pulse. Most cases of PAH occur in individuals with no family history of the disorder. Although some cases are due to mutations in the BMPR2 gene and inherited in an autosomal dominant pattern, a gene mutation has not yet been identified in most individuals. When PAH is inherited from an affected relative it is called "familial" PAH. Cases with no identifiable cause may be referred to as "idiopathic" PAH. PAH can also occur secondary to an underlying disorder such as connective tissue diseases, HIV infection, chronic hemolytic anemia, and congenital heart disease, to name a few. PAH can also be induced by certain drugs and toxins, for example fenfluramine and dexfenfluramine (appetite suppressants now banned by the FDA), toxic rapeseed oil, and amphetamines.
Source: Genetic and Rare Diseases Information Center (GARD), supported by ORDR-NCATS and NHGRI.Description Last Updated: Dec 31, 1969