In many instances, the cause is not known and is called primary pulmonary hypertension. Researchers have never been able to discover the exact reason behind the stiffening blood vessels associated with this illness, which is more commonly known as PPH.
In other cases, the stiffening can be due to some other medical problem, such as scleroderma. Researchers also don't know the exact cause of this problem, but people with scleroderma get tightening of their skin as well as their internal organs.
Currently, the only available treatment for pulmonary hypertension is getting hooked up to an IV to have a medicine called Flolan delivered directly into your vein. This requires you to have some kind of permanent access to your veins implanted under the skin.
But now, researchers have found that a medicine called bosentan, which can be taken by mouth, can improve breathing in those with pulmonary hypertension. Bosentan works in a similar way to Flolan by relaxing the blood vessels in the lung, thus lowering the pressure and allowing more oxygen to get into the bloodstream and to the rest of the body.
The study is published in the Oct. 6 issue of the medical journal The Lancet.
Looking at 32 people either with PPH or pulmonary hypertension due to scleroderma, study author Richard N. Channick, MD, and colleagues found that after taking bosentan for 12 weeks, these participants in the study had significant improvement in how far they could walk while those taking placebo continued to worsen.
Neither the researchers nor the patients knew if the patients were receiving bosentan or placebo. This is done in medical research so that people's perceptions of how they should be doing don't interfere with the findings of the study.
In addition, those taking bosentan had improvement in their heart function, which is also affected in people with pulmonary hypertension, and had overall improvement in their ability to function throughout the day compared to those taking placebo.
Channick and colleagues report that their findings are very promising for the treatment of this often-fatal medical problem but more research must done in the area to confirm the effectiveness and safety of bosentan before the drug can be approved for use. Channick is with the division of pulmonary and critical care medicine at the University of California San Diego, Calif.