Pulmonary arterial hypertension
Symptoms of PAH include shortness of breath (dyspnea) especially during exercise, chest pain, and fainting episodes.
The exact cause of PAH is unknown and although treatable, there is no known cure for the disease.
Approximately 15-20% of patients with PAH have heritable PAH. PAH has been linked to diet drugs such as Fen-Phen, Pondimin and Redux.
At this time, the disease may have progressed to a point where the patient is completely bedridden from shortness or breath or other symptoms. Researchers believe that injury to the layer of cells that line the small blood vessels of the lung, perhaps then causing or in concert with changes in the smooth muscle cells in the vessel wall, initiates blood vessel disease.
Along with the increased risk of diet pills, other exposures have been associated with the development of PAH. In addition, a very small percentage of HIV patients with AIDS develop PAH that is identical in presentation to primary PAH.
In terms of other exposures which may contribute to the development of PAH, few are validated in rigorous studies.
The risk of passing the abnormal gene from parent to offspring is 50% for each pregnancy and the risk is the same for males and females.
Of note, there now exist several publications associating PAH with mutations in other genes in a small number of subjects (e.g.