A stent coated with the erectile dysfunction drug sidenafil may someday help prevent arterial restenosis according to preliminary research presented at the American Heart Association's Basic Cardiovascular Sciences 2017 Scientific Sessions.

In this series of studies, the drug sildenafil showed potential in reducing both restenosis and blood clot formation. Sildenafil was originally developed as a medication for treating high blood pressure, and a side effect was the improvement of erectile dysfunction.

Researchers found:

• In laboratory tests, sildenafil reduced clumping of blood platelets by 30 percent;
• In rats, sildenafil increased the activity of an enzyme (protein kinase G, or PKG) that helps prevent the thickening of artery walls when given after injury to an artery, mimicking what might happen after stent placement;
• Activating the PKG pathway is an important part of sildenafil's action in preventing restenosis because the vessel injury such as stent implantation reduces PKG activity, increasing the thickening of artery walls and increasing the clumping of platelets.

"If similar results are found in clinical trials, sildenafil could be an ideal drug for coating drug-eluting stents or to give orally after stent implantation," said lead study author Han-Mo Yang, M.D., Ph.D., an associate professor in the division of cardiology at Seoul National University Hospital. The enzyme PKG is highly expressed in arteries as well as in the erectile tissue of the penis, and sildenafil works in both.

"Our study is limited by involving only animals. If clinical trials show that sildenafil reduces restenosis after stent placement, it could be used in the clinical setting right away because the drug is already used in the real world for other purposes," said Yang.

Co-authors are Sooryeonhwa Jin, B.S.; Sahmin Lee, M.D., Ph.D; and Hyo-Soo Kim, M.D., Ph.D.