Viagra may help life-threatening problem in children

Sometimes medications used for one problem can be used for other problems. Here is a terrific story where researchers looked at a mechanism to improve erectile dysfunction and thought about using it to improve something else.

Researchers reported this week in Circulation: Journal of the American Heart Association that the medication sildenafil (Viagra), taken over the course over a year, helped children with pulmonary arterial hypertension (PAH) walk further and breathe easier.

The new report is presented on the American Heart Association web site in a press release.

Scientists at UCSF Children's Hosptial say childhood PAH is a condition in which blood pressure in the arteries that supply the lungs is extremely high. The small blood vessels in the lungs become progressively narrower and their walls thicken, so they can’t carry as much blood. If the pressure soars high enough, the heart cannot keep up, causing fatigue, dizziness, shortness of breath and eventually heart failure and death. PAH can be inherited, caused by a congenital heart defect or result from another chronic heart or lung disease.

“Untreated, children usually die within one year of diagnosis,” says senior study author Ian Adatia, associate professor of pediatrics. “And even with the best therapy ... few patients live five years past diagnosis.”

When sildenafil is used to treat erectile dysfunction, the drug relaxes the smooth muscle of blood vessels, expanding the blood vessels and increasing blood flow.

The scientists say that those same effects should help people with pulmonary arterial hypertension, because expanding the blood vessels would prevent small blood vessels from becoming obstructed, and improve symptoms.

Adatia says the next step is conducting larger, randomized trials comparing sildenafil against placebo (an inactive substance) or other PAH medications. By the way, just fyi, Pfizer, Inc., maker of Viagra, funded the study.

You can find more about this study on the AHS web site at http://www.americanheart.org.